SIMCom SIM8905X Hardware Design

SIM8905 Series

Hardware Design

LTE Smart Module

SIMCom Wireless Solutions Limited

Building B, SIM Technology Building, No.633, Jinzhong Road

Changning District, Shanghai P.R. China

Tel: 86-21-31575100 [email protected] www.simcom.com

SIM8905 Series Hardware Design V1.07

Document Title:

Version:

SIM8905 Series Hardware Design

1.07

Date:

Status:

2020-06-08

Released

GENERAL NOTES

SIMCOM OFFERS THIS INFORMATION AS A SERVICE TO ITS CUSTOMERS, TO SUPPORT

APPLICATION AND ENGINEERING EFFORTS THAT USE THE PRODUCTS DESIGNED BY SIMCOM.

THE INFORMATION PROVIDED IS BASED UPON REQUIREMENTS SPECIFICALLY PROVIDED TO

SIMCOM BY THE CUSTOMERS. SIMCOM HAS NOT UNDERTAKEN ANY INDEPENDENT SEARCH

FOR ADDITIONAL RELEVANT INFORMATION, INCLUDING ANY INFORMATION THAT MAY BE IN THE

CUSTOMER’S POSSESSION. FURTHERMORE, SYSTEM VALIDATION OF THIS PRODUCT

DESIGNED BY SIMCOM WITHIN A LARGER ELECTRONIC SYSTEM REMAINS THE RESPONSIBILITY

OF THE CUSTOMER OR THE CUSTOMER’S SYSTEM INTEGRATOR. ALL SPECIFICATIONS

SUPPLIED HEREIN ARE SUBJECT TO CHANGE.

COPYRIGHT

THIS DOCUMENT CONTAINS PROPRIETARY TECHNICAL INFORMATION WHICH IS THE PROPERTY

OF SIMCOM WIRELESS SOLUTIONS LIMITED COPYING, TO OTHERS AND USING THIS DOCUMENT,

ARE FORBIDDEN WITHOUT EXPRESS AUTHORITY BY SIMCOM. OFFENDERS ARE LIABLE TO THE

PAYMENT OF INDEMNIFICATIONS. ALL RIGHTS RESERVED BY SIMCOM IN THE PROPRIETARY

TECHNICAL INFORMATION ， INCLUDING BUT NOT LIMITED TO REGISTRATION GRANTING OF A

PATENT , A UTILITY MODEL OR DESIGN. ALL SPECIFICATION SUPPLIED HEREIN ARE SUBJECT TO

CHANGE WITHOUT NOTICE AT ANY TIME.

SIMCom Wireless Solutions Limited

Building B, SIM Technology Building, No.633 Jinzhong Road, Changning District, Shanghai P.R.China

Tel: +86 21 31575100

Email: [email protected]

For more information, please visit:

https://www.simcom.com/download/list-863-en.html

For technical support, or to report documentation errors, please visit:

https://www.simcom.com/ask/ or email to: [email protected]

Copyright © 2020 SIMCom Wireless Solutions Limited All Rights Reserved.

www.simcom.com 2 / 88

SIM8905 Series Hardware Design V1.07

Version History

Date

2017-10-10

2017-11-13

2018-04-02

2019-01-25

2019-04-02

2019-12-20

2020-04-26

1.03

1.04

1.05

1.06

1.07

Version Description of change

1.01 Initial release

1.02 ADD SIM8905A description in the table1

Update Figure 17

Update Figure 1 and Figure 2.

ADD SIM8905E-W description in the table1.

Add chapter8: List of Recommended Devices

ADD SIM8905E-W description in the table1.

Modify document template format

Author

Bing Li

Xiaobo Bai

Bing Li

Xiaobo Bai

Bing Li

Bing Li

Bing Li

Bing Li

Bing Li www.simcom.com 3 / 88

SIM8905 Series Hardware Design V1.07

Contents

Version History ..................................................................................................................................... 3

Contents ................................................................................................................................................ 4

Table Index ............................................................................................................................................ 7

Figure Index .......................................................................................................................................... 9

1.

Introduction ................................................................................................................................. 10

1.1

Product Outline ......................................................................................................................... 10

1.2

Hardware Interface Overview ................................................................................................... 12

1.3

Hardware Block Diagram .......................................................................................................... 12

1.4

Functional Overview ................................................................................................................. 14

2.

Package Information ................................................................................................................... 17

2.1

Pin Assignment Overview ......................................................................................................... 17

2.2

Pin Description ......................................................................................................................... 18

2.3

Package Dimensions ................................................................................................................ 30

3.

Interface Application ................................................................................................................... 32

3.1

Power Supply ........................................................................................................................... 32

3.2

Power on/off ............................................................................................................................. 34

3.2.1

Power on ........................................................................................................................... 34

3.2.2

Power off ........................................................................................................................... 35

3.3

VRTC ........................................................................................................................................ 36

3.4

Output Power Management ...................................................................................................... 37

3.5

USB Interface ........................................................................................................................... 37

3.6

Linear Battery Charger ............................................................................................................. 38

3.6.1

Charging Control ............................................................................................................... 38

3.6.2

VBAT_SNS ....................................................................................................................... 39

3.6.3

VBAT_THERM .................................................................................................................. 40

3.7

UART/SPI/I2C .......................................................................................................................... 40

3.8

Secure Digital Interface ............................................................................................................ 41

3.9

Display Interface ....................................................................................................................... 42

3.10

Touch Screen Interface ............................................................................................................. 43

3.11

Camera Interface ...................................................................................................................... 44

3.12

Audio ........................................................................................................................................ 45

3.12.1

Microphone ..................................................................................................................... 46

3.12.2

Headset ........................................................................................................................... 47

3.12.3

Earpiece .......................................................................................................................... 48

3.12.4

Speaker ........................................................................................................................... 49

3.12.5

Microphone bias .............................................................................................................. 50

3.13

USIM Interface ......................................................................................................................... 51

www.simcom.com 4 / 88

SIM8905 Series Hardware Design V1.07

3.14

ADC .......................................................................................................................................... 52

3.15

Vibrator ..................................................................................................................................... 53

3.16

Antenna Interface ..................................................................................................................... 53

3.16.1

MAIN Antenna reference circuit ...................................................................................... 53

3.16.2

DRX Antenna reference circuit ........................................................................................ 54

3.16.3

GNSS Antenna reference circuit ..................................................................................... 55

3.16.4

WiFi/BT Antenna reference circuit ................................................................................... 56

3.16.5

GSM / CDMA 1X / UMTS / LTE layout guidance ............................................................. 56

3.16.6

Antenna Requirement ..................................................................................................... 58

3.16.7

Install the Antenna with RF Connector ............................................................................ 59

4.

PCB Layout .................................................................................................................................. 61

4.1

Stack-up Options ...................................................................................................................... 61

4.2

General Placement Guidelines ................................................................................................. 61

4.3

PCB Layout Guideline Details .................................................................................................. 61

4.3.1

RF Trace ........................................................................................................................... 61

4.3.2

Power/GND ....................................................................................................................... 61

4.3.3

USIM Card ........................................................................................................................ 62

4.3.4

MIPI_DSI/CSI .................................................................................................................... 62

4.3.5

USB .................................................................................................................................. 63

4.3.6

SDC Signal ....................................................................................................................... 63

4.3.7

Audio ................................................................................................................................. 64

5.

Electrical and Reliability ............................................................................................................. 65

5.1

Absolute Maximum Ratings ...................................................................................................... 65

5.2

Temperature Range .................................................................................................................. 65

5.3

Operating Voltage ..................................................................................................................... 65

5.4

Digital-logic Characteristics ...................................................................................................... 66

5.5

PWRKEY Characteristics ......................................................................................................... 67

5.6

VRTC Characteristics ............................................................................................................... 67

5.7

Current Consumption (VBAT=3.9V) ......................................................................................... 67

5.8

Electro-Static Discharge ........................................................................................................... 69

5.9

Module Operating Frequencies ................................................................................................ 69

5.10

Module Output power ............................................................................................................... 70

5.11

Module Receiving Sensitivity .................................................................................................... 71

5.12

WIFI Main RF Characteristics ................................................................................................... 72

5.13

BT Main RF Characteristics ...................................................................................................... 73

5.14

GNSS Main RF Characteristics ................................................................................................ 73

6.

Manufacturing .............................................................................................................................. 74

6.1

Top and Bottom View of SIM8905 ............................................................................................ 74

6.2

Typical SMT Reflow Profile ....................................................................................................... 75

6.3

Moisture Sensitivity Level (MSL) .............................................................................................. 75

6.4

Baking Requirements ............................................................................................................... 76

6.5

Packing System ........................................................................................................................ 76

7.

List of Recommended Devices .................................................................................................. 80

www.simcom.com 5 / 88

SIM8905 Series Hardware Design V1.07

A. Related Documents ....................................................................................................................... 83

B. Terms and Abbreviations .............................................................................................................. 84

C. Safety Caution ................................................................................................................................ 87

www.simcom.com 6 / 88

SIM8905 Series Hardware Design V1.07

Table Index

TABLE 1: SIM8905 SERIES FREQUENCY BANDS ...................................................................................................... 10

TABLE 2: GENERAL FEATURES ..................................................................................................................................... 14

TABLE 3: PIN CHARACTERS ........................................................................................................................................... 18

TABLE 4: PIN DESCRIPTION ........................................................................................................................................... 23

TABLE 5: RECOMMENDED ZENER DIODE .................................................................................................................. 33

TABLE 6: OUTPUT POWER MANAGEMENT SUMMARY ........................................................................................... 37

TABLE 7: LINEAR BATTERY CHARGER PERFORMANCE SPECIFICATIONS ...................................................... 39

TABLE 8: UART/SPI/I2C FUNCTIONAL ASSIGNMENTS ............................................................................................ 41

TABLE 9: DISPLAY INTERFACE PIN DEFINITIONS .................................................................................................... 42

TABLE 10: TOUCH SCREEN INTERFACE PIN DEFINITIONS ................................................................................... 43

TABLE 11: CAMERA INTERFACE PIN DEFINITIONS .................................................................................................. 44

TABLE 12: AUDIO INTERFACE PIN DEFINITIONS ...................................................................................................... 45

TABLE 13: ANALOG MICROPHONE INPUT PERFORMANCE .................................................................................. 46

TABLE 14: HEADPHONE OUTPUT PERFORMANCE SPECIFICATIONS ............................................................... 48

TABLE 15: EARPIECE OUTPUT PERFORMANCE SPECIFICATIONS ..................................................................... 49

TABLE 16: SPEAKER DRIVER OUTPUT PERFORMANCE SPECIFICATIONS ...................................................... 50

TABLE 17: MICROPHONE BIAS OUTPUT PERFORMANCE SPECIFICATIONS ................................................... 51

TABLE 18: USIM INTERFACE PIN DEFINITIONS ......................................................................................................... 51

TABLE 19: ADC PERFORMANCE PARAMETERS ........................................................................................................ 52

TABLE 20: EXAMPLE OF IMPEDANCE CONTROL OF MICROSTRIP LINE STRUCTURE ................................. 57

TABLE 21: EXAMPLE OF IMPEDANCE CONTROL OF COPLANAR WAVEGUIDE STRUCTURE ...................... 57

TABLE 22: ANTENNA REQUIREMENT ........................................................................................................................... 59

TABLE 23: LENGTH OF MIPI TRACES INSIDE THE MODULE ................................................................................. 62

TABLE 24: LENGTH OF USB TRACES INSIDE THE MODULE ................................................................................. 63

TABLE 25: LENGTH OF SD TRACES INSIDE THE MODULE .................................................................................... 64

TABLE 26: ABSOLUTE MAXIMUM RATINGS ................................................................................................................ 65

TABLE 27: TEMPERATURE RANGE ............................................................................................................................... 65

TABLE 28: OPERATING VOLTAGE ................................................................................................................................. 65

TABLE 29: 1.8 V DIGITAL I/O CHARACTERISTICS ..................................................................................................... 66

TABLE 30: USIM INTERFACE CHARACTERISTICS (USIM_VDD=1.8V/2.95V) ...................................................... 66

TABLE 31: SD INTERFACE CHARACTERISTICS (SD_LDO11 =1.8V) ..................................................................... 66

TABLE 32: SD INTERFACE CHARACTERISTICS (SD_LDO11 =2.95V) ................................................................... 66

TABLE 33: PWRKEY CHARACTERISTICS .................................................................................................................... 67

TABLE 34: VRTC CHARACTERISTIC ............................................................................................................................. 67

TABLE 35: CURRENT CONSUMPTION .......................................................................................................................... 67

TABLE 36: ESD PERFORMANCE PARAMETERS （ TEMPERATURE: 25 ℃ , HUMIDITY: 45% ）

........................ 69

TABLE 37: MODULE OPERATING FREQUENCIES ..................................................................................................... 69

TABLE 38: CONDUCTED TRANSMISSION POWER ................................................................................................... 70

TABLE 39: CONDUCTED RECEIVING SENSITIVITY .................................................................................................. 71

TABLE 40: REFERENCE SENSITIVITY QPSK PREFSENS (LTE) .......................................................................... 71

TABLE 41: WIFI MAIN RF CHARACTERISTICS ........................................................................................................... 72

TABLE 42: BT MAIN RF CHARACTERISTICS ............................................................................................................... 73

www.simcom.com 7 / 88

SIM8905 Series Hardware Design V1.07

TABLE 43: GNSS MAIN RF CHARACTERISTICS ......................................................................................................... 73

TABLE 44: MOISTURE CLASSIFICATION LEVEL AND FLOOR LIFE ....................................................................... 75

TABLE 45: BAKING REQUIREMENTS ............................................................................................................................ 76

TABLE 46: TRAY INFORMATION ..................................................................................................................................... 77

TABLE 47: SMALL CARTON INFORMATION ................................................................................................................. 78

TABLE 48: BIG CARTON INFORMATION ....................................................................................................................... 79

TABLE 49: RECOMMENDED TOUCH SCREEN CONTROLLER ............................................................................... 80

TABLE 50: RECOMMENDED CAPACITIVE TOUCH SCREEN MODELS ................................................................. 80

TABLE 51: RECOMMENDED SENSORS ....................................................................................................................... 80

TABLE 52: RECOMMENDED CAMERA SENSORS ..................................................................................................... 81

TABLE 53: RECOMMENDED LCM MODELS ................................................................................................................. 82

TABLE 54: RELATED DOCUMENTS ............................................................................................................................... 83

TABLE 55: TERMS AND ABBREVIATIONS .................................................................................................................... 84

TABLE 56: SAFETY CAUTION .......................................................................................................................................... 87

www.simcom.com 8 / 88

SIM8905 Series Hardware Design V1.07

Figure Index

FIGURE 1: MODULE BLOCK DIAGRAM ........................................................................................................................ 13

FIGURE 2: PIN ASSIGNMENT OVERVIEW ................................................................................................................... 17

FIGURE 3: DIMENSIONS OF SIM8905 (UNIT: MM) ..................................................................................................... 30

FIGURE 4: RECOMMENDED PCB FOOTPRINT OUTLINE (UNIT: MM) .................................................................. 31

FIGURE 5: LDO POWER SUPPLY REFERENCE CIRCUIT ........................................................................................ 32

FIGURE 6: DC-DC POWER SUPPLY REFERENCE CIRCUIT ................................................................................... 33

FIGURE 7: VBAT INPUT REFERENCE CIRCUIT .......................................................................................................... 33

FIGURE 8: POWERED ON/DOWN MODULE USING TRANSISTOR ........................................................................ 34

FIGURE 9: POWERED ON/DOWN MODULE USING BUTTON ................................................................................. 34

FIGURE 10: TIMING OF POWER ON MODULE ........................................................................................................... 35

FIGURE 11: KEEP-ALIVE CAPACITOR .......................................................................................................................... 36

FIGURE 12: NON-RECHARGEABLE BATTERY ........................................................................................................... 37

FIGURE 13: RECHARGEABLE BATTERY ..................................................................................................................... 37

FIGURE 14: USB REFERENCE CIRCUIT ...................................................................................................................... 38

FIGURE 15: USB_OTG REFERENCE CIRCUIT ........................................................................................................... 38

FIGURE 16: CHARGING CONTROL DIAGRAM ............................................................................................................ 39

FIGURE 17: BPD AND BTM FUNCTIONAL BLOCK DIAGRAM .................................................................................. 40

FIGURE 18: SD CARD REFERENCE CIRCUIT ............................................................................................................ 42

FIGURE 19: DISPLAY REFERENCE CIRCUIT .............................................................................................................. 43

FIGURE 20: PRIMARY CAMERA REFERENCE CIRCUIT ........................................................................................... 45

FIGURE 21: MICROPHONE REFERENCE CIRCUIT ................................................................................................... 46

FIGURE 22: HEADSET REFERENCE CIRCUIT ............................................................................................................ 47

FIGURE 23: EARPIECE REFERENCE CIRCUIT .......................................................................................................... 49

FIGURE 24: SPEAKER REFERENCE CIRCUIT ............................................................................................................ 50

FIGURE 25: USIM CARD REFERENCE CIRCUIT ........................................................................................................ 52

FIGURE 26: VIBRATOR REFERENCE CIRCUIT .......................................................................................................... 53

FIGURE 27: MAIN ANTENNA RECOMMENDED CIRCUIT ......................................................................................... 54

FIGURE 28: DRX ANTENNA RECOMMENDED CIRCUIT ........................................................................................... 54

FIGURE 29: GNSS ANTENNA RECOMMENDED CIRCUIT ........................................................................................ 55

FIGURE 30: GNSS ACTIVE ANTENNA CIRCUIT .......................................................................................................... 55

FIGURE 31: WIFI/BT ANTENNA RECOMMENDED CIRCUIT ..................................................................................... 56

FIGURE 32: TWO LAYER PCB MICROSTRIP STRUCTURE ..................................................................................... 57

FIGURE 33: TWO LAYER PCB COPLANAR WAVEGUIDE STRUCTURE ............................................................... 57

FIGURE 34: FOUR LAYER PCB COPLANAR WAVEGUIDE STRUCTURE 1# ........................................................ 58

FIGURE 35: FOUR LAYER PCB COPLANAR WAVEGUIDE STRUCTURE 2# ........................................................ 58

FIGURE 36: DIMENSIONS OF THE UF.L-R-SMT CONNECTOR (UNIT: MM) ......................................................... 60

FIGURE 37: TOP AND BOTTOM VIEW OF SIM8905 ................................................................................................... 74

FIGURE 38: TYPICAL SMT REFLOW PROFILE ........................................................................................................... 75

FIGURE 39: PRODUCTION FLOW OF MODULE PACKAGE ..................................................................................... 77

FIGURE 40: THE DIMENSION OF MODULE TRAY ...................................................................................................... 77

FIGURE 41: THE DIMENSION OF SMALL CARTON ................................................................................................... 78

FIGURE 42: THE DIMENSION OF BIG CARTON ......................................................................................................... 78

www.simcom.com 9 / 88

SIM8905 Series Hardware Design V1.07

1. Introduction

This document describes the electronic specifications, RF specifications, interfaces, mechanical characteristics and testing results of the SIMCom module. With the help of this document and other software application notes/user guides, users can understand and use module to design and develop applications quickly.

1.1 Product Outline

SIM8905/SIM8905A/SIM8905E/SIM8905E-W is a multi-mode and multi-band wireless smart module, which is based on Qualcomm MSM8909 platform. It includes baseband, memory, RF front end and required circuitry to support rich multimedia features, global location-based service, wireless connectivity, and air interface standards including GSM, WCDMA, TD-SCDMA, CDMA2000, and LTE.

In this document, the entire radio band configuration of SIM8905 series is described in the following table.

Table 1: SIM8905 Series frequency bands

Standard

GSM

WCDMA

CDMA2000/

EVDO

TD-SCDMA

LTE-FDD

BC0

B34

B39

FDD B1

FDD B2

FDD B3

FDD B4

FDD B5

Frequency

850MHz

900MHz

1800M Hz

1900M Hz

B1

B2

B4

B5

B8























SIM8905 SIM8905A































SIM8905E



































SIM8905-L







SIM8905E-W www.simcom.com 10 / 88

SIM8905 Series Hardware Design V1.07

LTE-TDD

Diversity

WIFI

FDD B7

FDD B8

FDD B12

FDD B13

FDD B17

FDD B20

FDD B25

FDD B26

TDD B38

TDD B39

TDD B40

TDD B41*

Diversity

802.11 a

802.11 b

802.11 g

802.11 n

2.4GHz





























































































BT

GNSS

5GHz

V2.1+EDR /

3.0+HS / V4.0 

BLE

GPS

GLONASS





BEIDOU 



























Battery-temperature monitoring

Adjust resistors

(R_S1/ R_S2 100K/39K 100K/39K in the Figure

17)

Support NTC 47K thermistor (B4050K)

47K

(B4050K)

100K/39K

47K

(B4050K)

100K/39K

47K

(B4050K)

100K/39K

47K

(B4050K)

DDR SDRAM 8Gb 8Gb 8Gb 8Gb 8Gb

Memory

Flash 8GB 8GB 8GB 8GB 8GB

NOTE

SIM8905’s TDD-LTE B41 bandwidth is 100MHz (2555 ~ 2655 MHz), the channel is 40240 ~ 41240.













With a small physical dimension of 40.5*40.5*2.8 mm and with the functions integrated, the module can meet almost any space requirement in users’ applications, such as smart phone, PDA, industrial handhold, www.simcom.com 11 / 88

SIM8905 Series Hardware Design V1.07 machine-to-machine and vehicle application, etc.

1.2 Hardware Interface Overview

The interfaces are described in detail in the next chapters include:

 Power Supply

 Charge management

 USB2.0 Interface

 SDIO /SD Interface

 LCM Interface(MIPI DSI)

 Camera Interface(MIPI CSI0/CSI1)

 USIM Interface

 GPIO

 ADC

 LDO Power Output

 Vibrator

 AUDIO Interface (Two inputs and Three outputs)

 UART Interface

 SPI Interface

 I2C Interface

1.3 Hardware Block Diagram

The block diagram of the module is shown in the figure below. www.simcom.com 12 / 88

720P LCD

Primary Camera (8MP)

Secondary Camera (5MP)

USB HS (Support OTG)

UIM Card1

UIM Card2

SD Card

TP/Sensor/Cam/others

Keypad Buttons

VBUS_5V

VBAT

Vibrator

ADC

Headset

Microphone

Earpiece

Speaker

SIM8905 Series Hardware Design V1.07

4 Lanes DSI

2 Lanes CSI

1 Lanes CSI

USB

UIM1

UIM2

SDC2

I2C

SPI

UART * 2

Keypad Buttons

GPIO

AP

Quad A7 w/ 512K L2

Camera ISP/VFE/Jpeg HW

Display Processor

Video

Graphics

Peripherals

SIM8905E-W do not support these functions

RFFE

Modem

Jolokia

4G/3G/2G MODEM

Core

MODEM/Voice

Processor

GNSS

Baseband

WWAN RX I/Q

GSM Phase

WWAN TX I/Q

RFFE

GNSS I/Q

WTR4905

RFFE

Linear

Charger

Output Power

Management

PM8909

SPMI BUS

PDM BUS

CODEC

Codec Digital

MSM8909

BT/WIFI

Baseband

Memory Support

WLAN CTRL

WLAN RX I/Q

WWAN TX I/Q

BT DATA

BT SSBI

WCN3610

Note2

EBI1

SDC1 eMMC flash +

LPDDR3

Front End

3 rd party

PA+SW

MAIN

DIVERSITY

SWITCH

MODULE

MMMB

Power

Amplifier

Modele

APT

QFE2101

DRX

LNA

Note1

GNSS

BT/WiFi

19.2M XO

Figure 1: module block diagram www.simcom.com 13 / 88

SIM8905 Series Hardware Design V1.07

1.4 Functional Overview

Table 2: General features

Feature

Power supply

Implementation

Single supply voltage 3.4

～

4.4V

，

recommend 3.8V.

Power saving

Application Processor

Memory

Current in sleep mode : <5mA

Quad ARM Cortex-A7 cores up to 1.1 GHz

32 kB L1, 512 kB L2 cache

ARMv7 32-bit architecture

LPDDR3 up to 533Mhz eMMC NAND flash

Default configuration: please refer to the table 1

Optional configuration : DDR SDRAM: 2GB; Flash:16GB

External memory via SD SD3.0; Support SD flash devices up to 32GB

Operating System

Charge management

Android OS 5.x/7.x/8.x

Linux3.18

Integrated 1.44 A linear charger for single-cell lithium-ion batteries

Display

Camera

Video performance

Audio

4-lane MIPI_DSI, 1.5Gbps each

HD(720P), 60fps

Primary camera: 2-lane MIPI_CSI, 8MP

Secondary camera: 1-lane MIPI_CSI, 5MP

Encode:

H.264 BP/MP –720p, 30fps

MPEG-4 SP / H.263 P0 –WVGA, 30fps

VP8 –WVGA, 30fps

Decode:

H.264 BP/MP/HP–1080p, 30 fps

MPEG-4 SP/ASP–1080p, 30 fps

DivX 4x/5x/6x–1080p, 30 fps

H.263 P0–WVGA, 30 fps

VP8 –1080p, 30 fps

(HEVC) H.265 MP 8 bit –1080p, 30 fps

Two inputs that support single-ended configurations

Three outputs: earpiece, stereo headphones, and mono class-D speaker driver

Voice codec support:

G711; Raw PCM; QCELP; EVRC, -B, -WB; AMR-NB, -WB; GSM-EFR,

-FR, -HR;

Audio codec support:

MP3; AAC+, eAAC; AMR-NB, -WB, G.711, WMA 9/10 Pro

Radio frequency bands

Transmitting power

Please refer to the table 1

GSM/GPRS:

 Class 4 : GSM850/EGSM900

 Class 1 : DCS1800/PCS1900

EDGE:

 Class E2: GSM850/EGSM900

 Class E1: DCS1800/PCS1900

TD-SCDMA:

 Class 2: B34/B39

CDMA:

 Class 3: BC0

UMTS: www.simcom.com 14 / 88

SIM8905 Series Hardware Design V1.07

Data Transmission

Throughput

Antenna

GNSS

Bluetooth

Wi-Fi/WAPI

GNSS

USIM interface

USB

Firmware upgrade

Physical characteristics

Temperature range

 Class 3: B1/B2/B4/B5/B8

LTE:

 Class 3:

B1/B2/B3/B4/B5/B7/B8/B12/B13/B17/B20/B25/B26/B38/B39/B40/B41

［ 1 ］

GPRS Class B, multi-slot class 33 operation, coding scheme: CS1-4,

DL maximum speed: 107kbps; UL maximum speed: 85.6kbps

EDGE multi-slot class 33 operation, coding scheme: MSC1-9,

DL maximum speed: 296kbps; UL maximum speed: 236.8kbps

TD-SCDMA 2.8Mbps(DL) 2.2Mbps(UL)

CDMA DORA 3.1Mbps(DL) 1.8Mbps(UL)

UMTS R99 speed: 384 kbps DL/UL

DC-HSDPA Category 24 - 42.2 Mbps, HSUPA Category 6 - 11.5 Mbps

LTE Category 4 - 150 Mbps (DL)

LTE Category 4 - 50 Mbps (UL)

GSM/UMTS/LTE main antenna.

UMTS/LTE auxiliary antenna

GNSS antenna

WIFI/BT antenna

GNSS engine (GPS,GLONASS and BD)

Protocol: NMEA

Specification: V2.1+EDR , 3.0+HS, V4.0 BLE

Tx power levels: Class 1 & 2

Support SoftAP Function

Encryption: WFA WPA/WPA2

Qos: WFA WMM , WMM PS

RF performance ：

11a power 15dBm, EVM<-25dB

11b power 17 dBm, EVM ≤ 35%

11g power 15dBm, EVM<-25dB

11n power 12 dBm, EVM<-27dB

Receiver type: GPS,GLONASS,BEIDOU

Sensitivity :

Tracking & Navigation : -160dBm

Reacquisition : -156dBm

Cold Start : -148dBm

TTFF@-130dBm: hot start <5s warm start <15s cold start <35s

CNo : 39dB/Hz@-130dBm

Support identity card: 1.8V/ 2.95V

Dual cards dual standby

USB 2.0 high speed interface

Firmware upgrade over USB interface

Dimension: 40.5*40.5*2.8mm

Weight: 10.6g

Normal operating temperature: -35 ℃ ~ +75 ℃

Extended operation temperature: -40°C to +85°C

［ 2 ］

Storage temperature: -40 ℃ ~ +90 ℃

NOTE

1. SIM8905’s TDD-LTE B41 bandwidth is 100MHz (2555 ~ 2655 MHz), the channel is 40240 ~ 41240. www.simcom.com 15 / 88

SIM8905 Series Hardware Design V1.07

2. Module is able to establish and maintain voice, data transmission, SMS and emergency call, etc. The performance may deviate slightly from the 3GPP specifications and will meet 3GPP specifications again when the temperature returns to normal operating temperature levels. www.simcom.com 16 / 88

SIM8905 Series Hardware Design V1.07

2. Package Information

2.1 Pin Assignment Overview

All functions of the module will be provided through 210 pads that will be connected to the customers’ platform. The following Figure is a high-level view of the pin assignment of the module.

GND

USB_DM

USB_DP

GND

USB_ID

USIM2_DET

USIM2_RST

USIM2_CLK

USIM2_DATA

USIM2_VDD

USIM1_DET

VBAT_BB

VBAT_BB

GND

MIC1P

GND_MIC

MIC2P

GND

EAR_P

EAR_M

SPK_P

SPK_M

USIM1_RST

USIM1_CLK

USIM1_DATA

USIM1_VDD

GND

VIB_DRV_N

PWM

TP_INT_N

TP_RST_N

SD_LDO12

GPIO_23

UART1_TXD

UART1_RXD

UART1_CTS

UART1_RTS

29

30

31

32

25

26

27

28

33

34

35

36

37

21

22

23

24

17

18

19

20

13

14

15

16

9

10

11

12

7

8

5

6

3

4

1

2

147

178 177 176 175 174 173 172 171

MIC_BIAS1 194 193 192 191 170

148

MIC_BIAS2 210

149

150

179

RESET

180

195

196

209 208 207

SIM8905

151 181 197

169

206 190 168

205 189 167

204 188 166

152 182 198 203 187 165

153

154

199 200 201 202

183 184 185 186

155 156 157 158 159 160 161 162

164

163

ACCL_INT1_N/GPIO_96

ACCL_INT2_N/GPIO_65

MAG_INT_N/GPIO_36

ALSP_INT_N/GPIO_94

GPIO_98

GPIO_0

GPIO_110

GPIO_97

GPIO_68

GPIO_69

GPIO_89

GPIO_88

GPIO_92

GPIO_31

KEY_VOL_DOWN_N

KEY_VOL_UP_N

UART2_TXD

UART2_RXD

SENSOR_I2C_SDA

SENSOR_I2C_SCL

GPIO_32

GND

GND

ANT_MAIN

GND

GND

CAM_I2C_SDA

CAM_I2C_SCL

CAM1_PWDN

CAM1_RST_N

CAM0_PWDN

CAM0_RST_N

GND

ANT-WIFI/BT

GND

CAM1_MCLK

CAM0_MCLK

93

92

91

90

97

96

95

94

102

101

100

99

98

106

105

104

103

110

109

108

107

77

76

75

81

80

79

78

85

84

83

82

89

88

87

86

74

53 54

POWER

GND

RESERVED

SDC2 USB Others UART USIM AUDIO GPIO Antenna TP

Figure 2: Pin assignment overview

LCM Camera www.simcom.com 17 / 88

SIM8905 Series Hardware Design V1.07

2.2 Pin Description

Table 3: Pin Characters

Pin# Pin Name

28

29

30

31

32

24

25

26

27

20

21

22

23

16

17

18

19

12

13

14

15

8

9

10

11

4

5

6

7

1

2

3

USB_ID

USIM2_DET

USIM2_RST

USIM2_CLK

USIM2_DAT

USIM2_VDD

USIM1_DET

USIM1_RST

USIM1_CLK

USIM1_DAT

USIM1_VDD

GND

VIB_DRV_N

PWM

TP_INT_N

TP_RST_N

SD_LDO12

VBAT_BB

VBAT_BB

GND

MIC1P

GND_MIC

MIC2P

GND

EAR_P

EAR_M

SPK_P

SPK_M

GND

USB_DM

USB_DP

GND

Voltage

MSM8909

Platform

Pin Name

Reset

Status

［ 1 ］

3.4~4.4V

3.4~4.4V

1.8V

1.8/2.95V

1.8/2.95V

1.8/2.95V

1.8/2.95V

1.8V

1.8/2.95V

GPIO_52

GPIO_51

GPIO_50

GPIO_49

GPIO_56

GPIO_55

1.8/2.95V

1.8/2.95V

GPIO_54

GPIO_53

1.8/2.95V

V_MPP

［ 3 ］

PM_MPP_2

［ 2 ］

PD

PD

1.8V

1.8V

1.8/2.95V

GPIO_13

GPIO_12

PD

PD

PD

PD

PD

PD

PD

PD

Wakeup

Interrupt

√

√

Note www.simcom.com 18 / 88

GPIO_23

UART1_TXD

UART1_RXD

UART1_CTS

UART1_RTS

SD_LDO11

SD_CLK

SD_CMD

SD_DATA0

SD_DATA1

SD_DATA2

SD_DATA3

SD_DET/GPIO_38

USB_BOOT

TP_I2C_SCL

TP_I2C_SDA

LCD_RST_N

LCD_TE

GND

MIPI_DSI_CLK_M

MIPI_DSI_CLK_P

MIPI_DSI_LANE0M

MIPI_DSI_LANE0P

MIPI_DSI_LANE1M

1.8V

1.8V

MIPI_DSI_LANE1P

MIPI_DSI_LANE2M

MIPI_DSI_LANE2P

MIPI_DSI_LANE3M

MIPI_DSI_LANE3P

GND

MIPI_CSI0_CLK_M

MIPI_CSI0_CLK_P

MIPI_CSI0_LN0_M

MIPI_CSI0_LN0_P

MIPI_CSI0_LN1_M

MIPI_CSI0_LN1_P

GND

MIPI_CSI1_CLK_M

MIPI_CSI1_CLK_P

MIPI_CSI1_LN0_M

MIPI_CSI1_LN0_P

1.8V

1.8V

1.8V

1.8V

1.8V

2.95V

1.8/2.95V

1.8/2.95V

1.8/2.95V

1.8/2.95V

1.8/2.95V

1.8/2.95V

1.8V

1.8V

1.8V

1.8V

SIM8905 Series Hardware Design V1.07

61

62

63

64

57

58

59

60

53

54

55

56

49

50

51

52

69

70

71

72

73

65

66

67

68

45

46

47

48

41

42

43

44

37

38

39

40

33

34

35

36 www.simcom.com 19 / 88

√

√

√

√

√

√

√

GPIO_25

GPIO_24

GPIO_23

GPIO_20

GPIO_21

GPIO_111

GPIO_112

GPIO_38

GPIO_37

GPIO_19

GPIO_18

PD

PD

PD

PD

PD

PD

PD

PD

PD

PD

PD

NP

PD

PD

PD

PD

PD

SIM8905 Series Hardware Design V1.07

SIM8905 Series Hardware Design V1.07

122

123

124

125

126

127

128

129

130

111

112

113

114

115

116

117

118

119

120

121

131

142

143

144

145

146

147

148

132

133

134

135

136

137

138

139

140

141

GND

SIM8905 ： ANT_DRX

SIM8905E-W ： NC

SIM8905-L ： NC

GND

VBAT_SNS

VBAT_THERM

GND

HPH_R

HPH_GND

HPH_L

HS_DET

GND

USB_VBUS

USB_VBUS

GND

GND

VBAT_RF

VBAT_RF

GND

GND

LDO5_1V8

GPIO_58

GPIO_99

PWRKEY

GPIO_95

GPIO_11

GPIO_10

GPIO_9

GPIO_8

GND

SIM8905

ANT_GNSS

SIM8905E-W ： NC

：

GND

GPIO_16

GPIO_17

LDO6_1V8

VRTC

CHARGE_SEL

ADC

LDO17_2V85

1.8V

1.8V

1.8V

1.8V

1.8V

1.8V

1.8V

1.8V

1.8V

5V

1.8V

1.8V

1.8V

1.8V

1.8V

2.85V

5V

3.4~4.4V

3.4~4.4V

GPIO_58

GPIO_99

GPIO_95

GPIO_11

GPIO_10

GPIO_9

GPIO_8

GPIO_16

GPIO_17

PM_OPT_1

［ 2 ］

PM_MPP_4

［ 2 ］

PD

PD

PD

PD

PD

PD

PD

PD

PD

√

√

√ www.simcom.com 21 / 88

GND

GND

GND

GND

GND

GND

GND

GND

GND

GND

GND

GND

GND

GND

RESIN_N

GND

GND

GND

RESERVED

RESERVED

RESERVED

RESERVED

RESERVED

RESERVED

RESERVED

RESERVED

RESERVED

GND

GND

GND

GND

GND

GND

GND

RESERVED

GND

GND

GND

RESERVED

GND

GND

173

174

175

176

177

178

179

180

165

166

167

168

169

170

171

172

181

182

183

184

185

186

187

188

189

157

158

159

160

161

162

163

164

149

150

151

152

153

154

155

156

SIM8905 Series Hardware Design V1.07 www.simcom.com 22 / 88

SIM8905 Series Hardware Design V1.07

198

199

200

201

202

203

204

205

190

191

192

193

194

195

196

197

RESERVED

RESERVED

GND

GND

MIC_BIAS1

RESERVED

RESERVED

RESERVED

GND

RESERVED

GND

GND

RESERVED

RESERVED

RESERVED

RESERVED

206

207

208

209

RESERVED

RESERVED

GND

GND

210 MIC_BIAS2

NOTE

1. NP = no-pull, PD = pull down, PU = pull up, KP = keeper

2. PM_XX means that it is a pin of PM8909

3. V_MPP is a selectable supply for MPP circuits; options include: VBAT, VREG_L2 (1.2V),

VREG_L5(1.8V)

Table 4: Pin description

Pin Name

Power Supply

VBAT_BB

VBAT_RF

VRTC

LDO6_1V8

Pin No. Type Description

1 ，

145

2

126

125

，

P

146 P

P

P

Main power supply for the

Baseband, and linear charger output

Main power supply for the RF

Coin cell or backup-battery charger supply and input

1.8V LDO output

Note

I t must be able to provide sufficient current up to 3A. TVS is recommended for surge protection

.

If unused, keep it open.

Power supply for external external www.simcom.com 23 / 88

LDO17_2V85

LDO5_1V8

129

111

P

P

2.85V LDO output

1.8V LDO output

SIM8905 Series Hardware Design V1.07

1.8V/2.95V LDO output circuit. A parallel

2.2uF~4.7uf capacitance is required.

If unused, keep it open.

Power supply for external external circuit. A parallel

2.2uF~4.7uf capacitance is required.

If unused, keep it open.

Power supply for external GPIO’s pull up and level shift circuits.

If unused, keep it open.

For SD pull-up only. LDO12_1V8

GND

32

3 ， 7 ， 12 ，

15 ， 27 ，

51 ， 62 ，

69 ， 76 ，

78 ， 85 ，

86 ， 88 ，

89 ， 120 ，

122 ，

130 ，

132 ，

135 ，

140 ，

143 ，

144 ，

147-150 ，

160-178 ，

180-182 ，

184-186 ，

188 ，

189 ，

192 ，

193 ，

198 ，

200 ，

201 ，

208 ， 209

P

P

USB

VBUS_USB

USB_DM

USB_DP

USB _ID

141

13

14

16

， 142 P

I/O

I/O

I

Input power from USB source

USB HS data negative

USB HS data positive

USB HS ID

USB insertion detection

Require differential impedance of 90ohm.

Default high level www.simcom.com 24 / 88

SIM8905 Series Hardware Design V1.07

SIM card

USIM2_DET

USIM2_RST

USIM2_CLK

USIM2_DAT

USIM2_VDD

USIM1_DET

17

18

19

20

21

22

USIM1_RST

USIM1_CLK

USIM1_DAT

USIM1_VDD

SDIO/SD card

SD_LDO11

SD_CLK

SD_CMD

SD_DATA0

SD_DATA1

SD_DATA2

38

39

40

41

42

43

SD_DATA3 44

SD_DET/GPIO_38 45

Touch Screen

TP_I2C_SDA 48

TP_I2C_SCL 47

TP_INT_N

TP_RST_N

LCD

PWM

30

31

29

LCD_RST_N

LCD_TE

49

50

MIPI_DSI_CLK_M 52

MIPI_DSI_CLK_P 53

23

24

25

26

I

O

O

I/O

P

I

I/O

O

I

O

O

I

O

O

O

O

I/O

P

I/O

I/O

I/O

I

P

O

I/O

I/O

O

USIM2 presence detection

USIM2 reset

USIM2 clock

USIM2 data

LDO 15 output for USIM2,

1.8V/2.95V

USIM1 presence detection

USIM1 reset

USIM1 clock

USIM1 data

LDO 14 output for USIM1,

1.8V/2.95V

LDO 11 output for SD card

Secure digital card clock

Secure digital card command

Secure digital card data bit 0

Secure digital card data bit 1

Secure digital card data bit 2

Secure digital card data bit 3

Secure digital card detection

1.8V power domain.

External pull-up resistor is required.

If unused, keep it open.

The 1.8V or 2.95v

USIM card is automatically identified

1.8V power domain.

External pull-up resistor is required.

If unused, keep it open.

The 1.8V or 2.95v

USIM card is automatically identified

Touch screen I2C

Touch screen interrupt

Touch screen reset

PWM control for external WLED driver

LCD reset

LCD tear effect

MIPI display serial interface

1.8V power domain.

External pull-up resistors are required. www.simcom.com 25 / 88

SIM8905 Series Hardware Design V1.07

MIPI_DSI_LANE0M 54

MIPI_DSI_LANE0P 55

MIPI_DSI_LANE1M 56

MIPI_DSI_LANE1P 57

MIPI_DSI_LANE2M 58

MIPI_DSI_LANE2P 59

MIPI_DSI_LANE3M 60

MIPI_DSI_LANE3P 61

Camera

MIPI_CSI0_CLK_M 63

MIPI_CSI0_CLK_P 64

MIPI_CSI0_LN0_M 65

MIPI_CSI0_LN0_P 66

MIPI_CSI0_LN1_M 67

MIPI_CSI0_LN1_P 68

MIPI_CSI1_CLK_M 70

MIPI_CSI1_CLK_P 71

MIPI_CSI1_LN0_M 72

MIPI_CSI1_LN0_P 73

CAM0_MCLK 74

CAM1_MCLK

CAM0_RST_N

CAM0_PWDN

CAM1_RST_N

CAM1_PWDN

CAM_I2C_SCL

82

83

75

79

80

81

CAM_I2C_SDA

Keypad

84

KEY_VOL_UP_N 95

KEY_VOL_DOWN_

N

PWRKEY

96

114

Sensors

SENSOR_I2C_SCL 91

SENSOR_I2C_SDA 92

ALSP_INT_N/

GPIO_94

MAG_INT_N/

GPIO_36

107

108

O

O

O

O

O

O

O

O

O

I/O

I

I

I

I

I

O

O

O

O

I

I

I

O

O

O

I

I

I

I

I

I

I

I/O

Primary camera serial interface

Secondary camera serial interface

Primary Camera master clock

Secondary Camera master clock

Primary Camera reset

Primary Camera power down

Secondary Camera reset

Secondary Camera power down

Camera I2C

1.8V power domain.

External pull-up resistors are required.

Volume up keypad

Volume down keypad

Power on keypad

If unused, keep it open.

If unused, keep it open.

Sensors I2C, pull-up resistors are needed externally

Ambient light and proximity sensor interrupt

Magnetic sensor interrupt

1.8V power domain.

External pull-up resistors are required. www.simcom.com 26 / 88

SIM8905 Series Hardware Design V1.07

ADC

VBAT_THERM

Audio

EAR_P

EAR_M

HPH_R

HPH_GND

HPH_L

HS_DET

GND_MIC

MIC2P

MIC1P

SPK_P

SPK_M

MIC_BIAS1

MIC_BIAS2

Vibrator

VIB_DRV_N

Antenna

ANT_MAIN

ANT_DRX

ACCL_INT2_N/

GPIO_65

ACCL_INT1_N/

GPIO_96

ADC

VBAT_SNS

109

110

133

ANT_GNSS

ANT-WIFI/BT

128

134

8

9

136

137

138

139

5

6

4

10

11

194

210

28

87

131

121

77

I

I

Accelerate sensor interrupt 2

Accelerate sensor interrupt 1

I

I

I

Battery voltage sense

Analog to digital converter

Battery thermistor

Must be used.

Maximum input voltage is 1.7V.

Maximum input voltage is 4.5V.

If unused, keep it open.

O

O

O

I

O

I

P

I

I

O

O

O

O

Earpiece output, positive

Earpiece output, negative

Headphone output, right channel

Headphone ground reference

Headphone output, left channel

Headset detection

Microphone input 2 ground reference

Microphone input 2, positive

Microphone input 1, positive

Speaker driver output, positive

Speaker driver output, negative

Microphone bias 1

Microphone bias 2

Bias for external

MEMS Microphone ；

ECM: keep

MIC_BIAS1/2 open

P,O

Vibration motor driver output control

I/O

I

I

I/O

2G/3G/4G main antenna port

4G diversity antenna port

GNSS antenna port

WIFI/BT antenna port

SIM8905 ： ANT_MAIN

SIM8905E-W ： NC

SIM8905 ： ANT_DRX

SIM8905E-W ： NC

SIM8905-L ： NC

SIM8905 ：

ANT_GNSS

SIM8905E-W ： NC www.simcom.com 27 / 88

SIM8905 Series Hardware Design V1.07

GPIO_97

GPIO_110

GPIO_0

GPIO_98

GPIO_58

GPIO_99

GPIO_95

GPIO_11

GPIO_10

GPIO_9

GPIO_8

GPIO_16

GPIO_17

RESIN_N

Others

USB_BOOT

GPIO_23

GPIO_31

UART1_TXD

UART1_RXD

UART1_CTS

UART1_RTS

GPIO_32

UART2_RXD

UART2_TXD

GPIO_92

GPIO_88

GPIO_89

GPIO_69

GPIO_68

CHARGE_SEL

RESERVED

RESERVED

117

118

119

123

124

179

103

104

105

106

112

113

115

116

90

93

94

98

99

100

101

102

46

33

97

34

35

36

37

127

151 ，

152 ，

153 ，

154 ，

155 ，

156 ，

157 ，

158 ，

I/O

I/O

I/O

I/O

I/O

I

I/O

I/O

I/O

I/O

I/O

I/O

I/O

I/O

I/O

I/O

I/O

I/O

I/O

I/O

I/O

I/O

I

I/O

I/O

I/O

I/O

I/O

I/O

I

Force boot from USB interface

GPIO

GPIO

UART1_TXD

UART1_RXD

UART1_CTS

UART1_RTS

GPIO

UART2_RXD

UART2_TXD

GPIO

GPIO

GPIO

GPIO

GPIO

GPIO

GPIO

GPIO

GPIO

GPIO

GPIO

GPIO

GPIO

GPIO

GPIO

GPIO

GPIO

GPIO

Reset

Option configuration control bit1 ：

Hi-Z → internal charger is used

GND → external charger is used

Do not connect www.simcom.com 28 / 88

159 ，

183 ，

187 ，

190 ，

191 ，

195 ，

196 ，

197 ，

199 ，

202 ，

203 ，

204 ，

205 ，

206 ， 207

NOTE

1. Leave unused pins floating unless otherwise specified.

SIM8905 Series Hardware Design V1.07 www.simcom.com 29 / 88

2.3 Package Dimensions

SIM8905 Series Hardware Design V1.07

Figure 3: Dimensions of SIM8905 (Unit: mm) www.simcom.com 30 / 88

SIM8905 Series Hardware Design V1.07

Figure 4: Recommended PCB footprint outline (Unit: mm) www.simcom.com 31 / 88

SIM8905 Series Hardware Design V1.07

3. Interface Application

3.1 Power Supply

The power supply pins of SIM8905 include VBAT_RF and VBAT_BB. VBAT_RF directly supplies the power to RF PA; VBAT_BB supplies the power to the baseband system. The power supply of SIM8905 ranges from 3.4V to 4.4V, and 3.9V is recommended. It must be able to provide sufficient current up to 3A for the high-power transmitting. Make sure the input voltage will never drop below 2.9V.

If the DC input voltage is +5V and customers do not care about the power efficiency, a high-current

low-dropout regulator is recommended. Figure 5 is the reference design.

DC INPUT

C101

100uF

+

C102

1uF

2

U101 MIC29302

Vin Vout

1

On/Off

PWR_CTRL 3

FB

4

5 R101

100K

+

C103

330uF

C104

100nF

R103

470R

VBAT

R102

47K

Figure 5: LDO power supply reference circuit

NOTE

1. To ensure a proper behavior of the regulator under light load, an extra minimum load (R103 in

Figure 5) is required, because the current SIM8905 consumed is very small in sleep mode and

power off mode. For more details about minimum load, please refer to specification of MIC29302.

To increase power efficiency, the switching mode DC-DC converter is preferable, especially when DC input voltage is quite high. The following figure is the reference design, and it is recommended to reserve a

proper ferrite bead (FB101 in Figure 6) in series for EMI suppression.

www.simcom.com 32 / 88

SIM8905 Series Hardware Design V1.07

DC INPUT U101

1

Vin

LM2596-ADJ

Vout

C101

100uF

+

C102

1uF

5

PWR_CTRL

On/Off

3

FB

2

4

L101

100uH

D102 C103

MBR360

330uF

+

C104

100nF

FB101

270R@100MHz

R101

2.2K

VBAT

R102

1K

Figure 6: DC-DC power supply reference circuit

For battery-powered application, the 3.7V lithium battery can be connected to SIM8905 VBAT pins directly, but other types of battery must be used carefully, since their maximum voltage may rise over the absolute maximum voltage of the module. When battery is used, the total impedance between battery and VBAT pins should be less than 150mΩ.

In any case mentioned above, at the VBAT input pins side, please take Figure 7 as a reference:

VBAT_RF VBAT

VBAT_BB

C103

33pF

C101

100uF

C105

220uF

D101

5.1V

500mW

GND

Module

Figure 7: VBAT input reference circuit

Where C101 is a 100uF tantalum capacitor with low ESR; C105 is a 220uF tantalum capacitor with low ESR;

33pF and 10pF capacitors are used for eliminating the high frequency interference; 5.1V/500mW zener diode can protect the module against voltage surge.

All of these components should be placed as close to VBAT pins as possible.

Table 5: Recommended zener diode

No.

1

2

3

4

Vendor

On semi

Prisemi

Vishay

Crownpo

Part number

MMSZ5231BT1G

PZ3D4V2H

MMSZ4689-V

CDZ55C5V1SM

Power(watts)

500mW

500mW

500mW

500mW

Packages

SOD123

SOD323

SOD123

0805 www.simcom.com 33 / 88

SIM8905 Series Hardware Design V1.07

3.2 Power on/off

3.2.1 Power on

Users can power on SIM8905 by pulling down the PWRKEY pin for more than 2 second then release. This pin is already pulled up to 1.8V internally, so external pull up is not necessary. Reference circuits are shown as below:

R

1.8V

PWRKEY

1K

4.7K

47K

PMU

Module

Figure 8: Powered on/down module using transistor

R

1.8V

PWRKEY

1K

PMU

Module

Figure 9: Powered on/down module using button

The power on sequence is illustrated in Figure 10.

www.simcom.com 34 / 88

SIM8905 Series Hardware Design V1.07

VBAT

PWRKEY

LDO5_1V8

LDO6_1V8

Others

175ms

250us t>2s

Software Controlled

Figure 10: Timing of power on module

NOTE

1. Make sure that VBAT is stable before pulling down PWRKEY pin. The time between them is no less than 50ms.

2. PWRKEY pin cannot be pulled down all the time.

3. Please pay attention to the maximum conditions (such as voltage and temperature range) allowed by the module before starting the module,otherwise exceeding the absolute maximum value of the module may cause permanent damage to the module.

3.2.2 Power off

Users can turn off SIM8905 by pulling down the PWRKEY pin for more than 1 second. After the module detects that the PWRKEY is low level, a prompt window will pop up on the screen to confirm whether to execute the shutdown action.

Module can also be forced to shut down by pulling down PWRKEY for more than 8 seconds.

NOTE

1. The VBAT power supply circuit of the module can be cut off in the customer's hardware design.

2. It is recommended to add a low-cost MCU, which can control the PWRKEY to power on and power off the module, as well as the hardware watchdog to protect the normal operation.

3. Do not directly cut off the power supply VBAT of the module when the module is working normally, otherwise the internal flash of the module will be damaged. It is strongly recommended to shut www.simcom.com 35 / 88

SIM8905 Series Hardware Design V1.07 down the module through PWRKEY or AT command before disconnecting the power supply VBAT of the module.

3.3 VRTC

VRTC is the power supply for RTC circuit and charger output for coin cell or backup battery. If RTC support is needed when the battery is removed, a qualified coin cell or keep-alive capacitor is required on the VRTC pin. When VBAT is present and valid, coin cell charging is enabled through software control and powered from VBAT.

 If the RTC fails, the module can synchronize the RTC clock through data connection after power on.

 Refer to table 34: VRTC characteristics for VRTC hardware parameters.

 Input voltage range of VRTC power supply is 2.0-3.25V, typical value is 3.0V, and the average current consumption is 5ua when VBAT is disconnected and VRTC is connected only.

 RTC error is 50ppm w hen the module is powered by VBAT; RTC error is 200ppm

w hen the module is powered by VRTC .

 When the rechargeable button battery is connected externally, the ESR of button battery is required to be less than 2K. It is recommended to use Seiko's ms621fe fl11e.

 If VRTC PIN is connected with large capacitance externally, the recommended capacitance value is

100uF with low ESR, which can keep the real-time clock for about 45 seconds.

Reference circuits are shown as below:

Keep-alive capacitor:

VRTC

Module

RTC

Capacitor

Figure 11: Keep-alive capacitor

Non-rechargeable battery:

Non-rechargeable battery

VRTC

Module

RTC www.simcom.com 36 / 88

SIM8905 Series Hardware Design V1.07

Figure 12: Non-rechargeable battery

Rechargeable battery:

Rechargeable battery

VRTC

Module

RTC

Figure 13: Rechargeable battery

VRTC typical voltage is 3.0V, and the current consumption is about 5uA when VBAT is absence. For

electrical characteristics, please refer to Table 31: VRTC characteristic.

3.4 Output Power Management

Table 6: Output power management summary

Pin Name Pin#

LDO5_1V8

LDO6_1V8

SD_LDO11

SD_LDO12

USIM1_VDD

111

125

38

32

26

USIM2_VDD 21

LDO17_2V85 129

Specified range (V)

1.8

1.8

2.95

1.8/2.95

1.8/2.95

1.8/2.95

2.85

Rated current (mA) Expected use

50

200

600

50

50

50

420

Force USB boot

Display, camera, sensors

SD/MMC card

For SD signals pull-up

USIM 1

USIM 2

Display, camera, sensors

3.5 USB Interface

SIM8905 provides one High-speed USB 2.0 interface, used for software upgrading, debugging, charging, etc. www.simcom.com 37 / 88

SIM8905 Series Hardware Design V1.07

USB_VBUS

USB_DP

VBUS

USB_DP

USB_DM

USB_DM

USB_ID 1uF

<1pF

GND GND

Module Connector

Figure 14: USB reference circuit

In addition, SIM8905 supports OTG function, but external 5V power supply is required.

External 5V

USB_VBUS

USB_DP

VBUS

USB_DP

USB_DM USB_DM

USB_ID USB_ID

<1pF

GND

Module

GND

Connector

Figure 15: USB_OTG reference circuit

3.6 Linear Battery Charger

SIM8905 module integrates a 1.44A linear battery charger for single-cell lithium-ion batteries.

3.6.1 Charging Control

Battery charging is controlled by a PMIC state-machine. The first step in the automated charging process determines if trickle charging is needed. Charging of a severely depleted battery must begin with trickle charging to limit the current, avoid pulling VDD down, and protect the battery from more charging current than it can handle. Once a minimum battery voltage is established using trickle charging, constant-current charging is enabled to charge the battery quickly – this mode is sometimes called fast charging. Once the www.simcom.com 38 / 88

SIM8905 Series Hardware Design V1.07 battery approaches its target voltage, the charge is completed using constant-voltage charging.

V

BAT

V

BAT-MAX

4.2V

450mA/1440mA

I

BAT

I

BAT-MAX

V

WEAK

V

TRKL

3.2V

2.8V

I

TRKL-B

450 mA

I

TRKL-A

90mA

TRKL-A TRKL-B CC CV

Time

Figure 16: Charging control diagram

Table 7: Linear battery charger performance specifications

Parameter

ITRKL-A

ITRKL-B

VTRKL

VWEAK

VBAT_MAX

IBAT_MAX

Comments

Trickle-A Charging current

Trickle-B Charging current

Trickle-B threshold voltage range

Programmable, 15.62 mV steps

Weak battery threshold range

Programmable, 18.75 mV steps

Maximum battery voltage

Programmable, 25 mV steps

Fast charging current range

Programmable, 90mA steps

Min Typ Max

81

405

90

450

99

495

2.5

3.0

4

90

2.796 2.984

3.206 3.581

4.2 4.775

1440

Units mA mA

V

V

V mA

3.6.2 VBAT_SNS

VBAT_SNS is used for battery voltage sensing, the typical input range is 2.5V~4.5V.

VBAT_SNS pin cannot be unused. It is connected to the battery positive pin when the lithium battery is used for module power supply. it is connected to the module VBAT_BB, which is powered by LDO or DCDC. www.simcom.com 39 / 88

SIM8905 Series Hardware Design V1.07

3.6.3 VBAT_THERM

VBAT_THERM is used for battery-temperature monitoring (BTM) and  ba tte ry

To support this function, the 47K NTC thermistor (B-Constant =4050K) is required in battery pack, and the cold/hot comparator threshold settings should be 70%/35%. The allowed charging temperature range from

-2 ℃ to 52 ℃ , ± 2 ℃ .

If this function is not used, connecting a 47K resistor is recommended.

Module

VBAT_RF

VBAT_BB

PMU

VREF_BAT_THM

VBAT_SNS

R_S1

100K±1%

BAT_THERM

Present +

95%

R_S2

39K±1%

Cold

Hot

+

70%

+

35%

GND

47K NTC

(B=4050K)

Battery Pack

+

Figure 17: BPD and BTM functional block diagram

3.7 UART/SPI/I2C

SIM8905 provides several sets of GPIOs which are available as BLSP (BAM-enabled low-speed peripheral) interfaces that can be configured to support various interface combinations, as shown in the following table.

The operation voltage is 1.8V www.simcom.com 40 / 88

SIM8905 Series Hardware Design V1.07

Table 8: UART/SPI/I2C functional assignments

Pin Name Pin#

Default Function Function 1

BLSP1_UART_TX BLSP1_SPI_MOSI

Alternative

Function 2

UART2_TXD

UART2_RXD

SENSOR_I2C_SDA

GPIO_9

GPIO_10

GPIO_11

GPIO_16

GPIO_17

TP_I2C_SDA

TP_I2C_SCL

UART1_TXD

94

93

92

SENSOR_I2C_SCL 91

GPIO_8 119

118

117

116

123

124

48

47

34

BLSP1_UART_RX BLSP1_SPI_MISO

BLSP1_I2C_SDA BLSP1_SPI_CS_N BLSP1_UART_CTS

BLSP1_I2C_SCL

GPIO

BLSP1_SPI_CLK

BLSP6_SPI_MOSI

BLSP1_UART_RTS

GPIO

GPIO

GPIO

GPIO

BLSP6_SPI_MISO

BLSP6_SPI_CS_N

BLSP6_SPI_CLK

BLSP5_SPI_MOSI

BLSP6_I2C_SDA

BLSP6_I2C_SCL

GPIO

BLSP5_I2C_SDA

BLSP5_SPI_MISO

BLSP5_SPI_CS_N

BLSP5_I2C_SCL BLSP5_SPI_CLK

BLSP2_UART_TX BLSP2_SPI_MOSI

UART1_RXD

UART1_CTS

UART1_RTS

CAM_I2C_SDA

35

36

37

84

BLSP2_UART_RX BLSP2_SPI_MISO

BLSP2_UART_CTS BLSP2_SPI_CS_N BLSP2_I2C_SDA

BLSP2_UART_RTS BLSP2_SPI_CLK

BLSP3_I2C_SDA

BLSP2_I2C_SCL

CAM_I2C_SCL 83 BLSP3_I2C_SCL

NOTE

1. UART: can be used as a diagnostic port, up to 4 Mbps;

2. I2C: supports master-only mode; up to 3.4 MHz, 2.2Kohm pull-up resistors are needed externally;

3. SPI: supports master-only mode; up to 52 MHz.

3.8 Secure Digital Interface

SIM8905 provides one 4-bit secure digital interface, which supports the following standards:

 SD Specifications Part 1 Physical Layer Specification Version 3.00

 Part A2 SD Host Controller Standard Specification Version 3.00

 Part E1 SDIO Specification Version 3.00 www.simcom.com 41 / 88

SIM8905 Series Hardware Design V1.07

SD_LDO12

Module

1uF

SD_DATA2

SD_DATA3

SD_CMD

SD_LDO11

SD_CLK

SD_DATA0

SD_DATA1

33R is required for high-speed operation; placed close to the module

33R

LDO5_1V8

SD_DET

1M

NM ： Not Mounting

Reserved

TVS

C<15pF

SD Card

1 DAT2

2 DAT3

3 CMD

4 VDD

5 CLK

6 VSS

7 DAT0

8 DAT1

11 GND

12 GND

13 GND

14 GND

9 DET_SW

10 COMMON

1uF 33pF

Placed close to SD card

Figure 18: SD card reference circuit

3.9 Display Interface

SIM8905 provides a 4-lane MIPI_DSI, with 1.5 Gbps per lane high-speed mode bandwidth, to support 720p

HD display.

PWM is used as PWM control for external WLED driver.

Table 9: Display interface pin definitions

Pin Name

PWM

LCD_RST_N

LCD_TE

MIPI_DSI_CLK_M

MIPI_DSI_CLK_P

Pin#

29

49

50

52

53

MIPI_DSI_LANE0M 54

MIPI_DSI_LANE0P 55

MIPI_DSI_LANE1M 56

MIPI_DSI_LANE1P 57

MIPI_DSI_LANE2M 58

MIPI_DSI_LANE2P 59

MIPI_DSI_LANE3M 60

MIPI_DSI_LANE3P 61

Type

O

O

O

O

O

O

O

O

I

O

O

O

O

Description

PWM control for external WLED driver

LCD reset

LCD tear effect

MIPI display serial interface www.simcom.com 42 / 88

SIM8905 Series Hardware Design V1.07

If only 2-lane MIPI_DSI is needed, just leave LANE2 and LANE3 floating.

Module

VBAT

LED+

PWM

WLED driver

LED-

1M

LDO17_2V85

LDO6_1V8

LCD_RST_N

LCD_TE

MIPI_DSI_LANE1_M

MIPI_DSI_LANE1_P

MIPI_DSI_CLK_M

MIPI_DSI_CLK_P

MIPI_DSI_LANE0_M

MIPI_DSI_LANE0_P

1uF 1uF

LCM

1 GND

2 LED+

3 LED+

4 LED-

5 LED-

6 LCD_ID

7 VCC(2.8V)

8 GND

9 GND

10 VCC_IO

11 RESET

12 TE

13 NC

14 NC

15 GND

16 DSI_D1-

17 DSI_D1+

18 GND

19 DSI_CLK-

20 DSI_CLK+

21 GND

22 DSI_D0-

23 DSI_D0+

24 GND

25 GND

Figure 19: Display reference circuit

3.10 Touch Screen Interface

Table 10: Touch screen interface pin definitions

Pin Name

TP_I2C_SDA

TP_I2C_SCL

TP_INT_N

TP_RST_N

Pin#

48

47

30

31

Type

I/O

O

I

O

Description

Touch screen I2C data

Touch screen I2C clock

Touch screen interrupt

Touch screen reset

NOTE

1. TP_I2C: supports master-only mode; 2.2Kohm pull-up resistors are needed externally; www.simcom.com 43 / 88

SIM8905 Series Hardware Design V1.07

3.11 Camera Interface

SIM8905 supports two cameras: 2-lane MIPI_CSI primary camera up to 8MP resolution and 1-lane

MIPI_CSI secondary camera up to 5MP resolution.

Table 11: Camera interface pin definitions

Pin Name Pin#

MIPI_CSI0_CLK_M 63

MIPI_CSI0_CLK_P 64

MIPI_CSI0_LN0_M 65

MIPI_CSI0_LN0_P 66

MIPI_CSI0_LN1_M 67

MIPI_CSI0_LN1_P 68

MIPI_CSI1_CLK_M 70

MIPI_CSI1_CLK_P 71

MIPI_CSI1_LN0_M 72

MIPI_CSI1_LN0_P 73

CAM0_MCLK 74

CAM1_MCLK

CAM0_RST_N

75

79

CAM0_PWDN

CAM1_RST_N

CAM1_PWDN

CAM_I2C_SCL

CAM_I2C_SDA

80

81

82

83

84

Type

I

O

O

O

O

I/O

I

O

O

O

I

I

I

I

I

I

I

I

Description

Primary camera serial interface

Secondary camera serial interface

Primary Camera master clock

Secondary Camera master clock

Primary Camera reset

Primary Camera power down

Secondary Camera reset

Secondary Camera power down

Camera I2C clock

Camera I2C data www.simcom.com 44 / 88

SIM8905 Series Hardware Design V1.07

Module

LDO17_2V85

LDO6_1V8

MIPI_CSI0_CLK_P

MIPI_CSI0_CLK_M

MIPI_CSI0_LN0_P

MIPI_CSI0_LN0_M

MIPI_CSI0_LN1_P

MIPI_CSI0_LN1_M

CAM0_MCLK

CAM0_RST_N

CAM0_PWDN

2.2uF

2.2uF

100nF 100nF

Primary

Camera

AGND

VCM

AVDD

DVDD

VDD_IO

GND

MCP

MCN

GND

MDP0

MDN0

GND

MDP1

MDN1

GND

MCLK

RESET

PWDN

2.2K

2.2K

CAM_I2C_SCL

CAM_I2C_SDA

SCL

SDA

Figure 20: Primary camera reference circuit

3.12 Audio

SIM8905 provides two microphone inputs and three outputs including earpiece, stereo headphones, and mono class-D speaker driver.

Table 12: Audio interface pin definitions

Pin Name

EAR_P

EAR_M

HPH_R

HPH_GND

HPH_L

HS_DET

GND_MIC

MIC2P

MIC1P

SPK_P

SPK_M

Pin#

139

5

6

4

10

11

8

9

136

137

138

Type

I

I

I

P

O

O

O

O

O

I

O

Description

Earpiece output, positive

Earpiece output, negative

Headphone output, right channel

Headphone ground reference

Headphone output, left channel

Headset detection

Microphone input 2 ground reference

Microphone input 2, positive

Microphone input 1, positive

Speaker driver output, positive

Speaker driver output, negative www.simcom.com 45 / 88

MIC_BIAS1

MIC_BIAS2

3.12.1 Microphone

194

210

O

O

SIM8905 Series Hardware Design V1.07

Microphone bias 1

Microphone bias 2

Close to microphone

10pF

MIC1P route as differential pair

& shielded by GND

10pF

GND_MIC

Module

10pF

33pF

ESD

33pF

33pF

ESD

Electret

Microphone

Figure 21: Microphone reference circuit

NOTE

1. Internal MIC_BIAS pull-up is used to reduce BOM cost and PCB routing.

2. Single-ended capless input is the only supported configuration, but differential routing is recommended.

Table 13: Analog microphone input performance

Parameter Test conditions Min Typ Max Units

Microphone amplifier gain = 0 dB (minimum gain)

Input referred noise Single-ended, A-weighted, capless

Signal-to-noise ratio Single-ended, A-weighted, capless

THD+N ratio

Analog input = -1 f = 1.02 kHz; single-ended input; 200

Hz to 20 kHz bandwidth; capless dBV

Microphone amplifier gain = 6 dB

-

-

92.0

Input referred noise Single-ended, A-weighted, capless

Signal-to-noise ratio Single-ended, A-weighted, capless

THD+N ratio f = 1.02 kHz; single-ended input;

-

91.0

-

19.3 25.1

94.0 -

-86.0 -70.0 dB

5.9 7.1

92.5 -

-85.0 -70

µVrms dB

µVrms dB dB www.simcom.com 46 / 88

SIM8905 Series Hardware Design V1.07

Analog input = -1 dBV

200 Hz to 20 kHz bandwidth; capless

Microphone amplifier gain = 24 dB (maximum gain)

Input referred noise Single-ended, A-weighted, capless -

Signal-to-noise ratio Single-ended, A-weighted, capless

THD+N ratio

Analog input = -1 dBV

General requirements f = 1.02 kHz; single-ended input;

200 Hz to 20 kHz bandwidth; capless

84.2

-

Single-ended 1 kHz input. Input signal

Full-scale input level required to get 0 dBFS digital voltage output

-0.5

Input impedance

Capless input

Input disabled

1.0

3.0

Input capacitance Capless input -

3.4 4.2

85.4 -

µVrms dB

-82.4 -76.0 dB

0

-

-

-

0.5

-

-

15 dBV

MΩ

MΩ pF

3.12.2 Headset

Stereo class-

AB headphone supports 16 Ω, 32 Ω, and up to 50 KΩ loads. Its typical output power at 1.02

KHz and THD + N ≤ 1% is:

 21.5 mW with

16 Ω loads, 0 dBFS and -4.5 dB gain

 30.8 mW with 32 Ω loads, 0 dBFS and 0 dB gain

A 100K

Ω pull-down resistor is integrated at HPH_L pin, which could be used for mechanical insertion or

removal detection through HS_DET pin. Figure 22 shows the reference circuit for normally-closed (NC) type

headset jack.

HS_DET

HPH_R

HPH_L

MIC2P

GND_MIC

HPH_GND

Module

0R

0R

Close to headset jack

1000 OHM@100MHZ

1000 OHM@100MHZ

1000 OHM@100MHZ

1000 OHM@100MHZ

33pF 33pF 33pF

1000 OHM@100MHZ

1000 OHM@100MHZ

100K

TVS

Headset Jack

Figure 22: Headset reference circuit www.simcom.com 47 / 88

SIM8905 Series Hardware Design V1.07

NOTE

1. SIM8905 also supports NO/NC type headset jack with detect pin on HPH_L or GND.

2. HPH has a negative swing and requires a bi-directional TVS diode.

Table 14: Headphone output performance specifications

Parameter Test conditions Min Typ Max Units

Output power

16 Ω load f = 1.02 kHz, 0 dB FS; VDD_CP* = 1.95 V 15.6 21.5

25.5 mW

32 Ω load f = 1.02 kHz, 0 dB FS; VDD_CP* = 1.95 V 27.0 30.8

32.0 mW

Full-scale 16 Ω load f = 1.02 kHz, 0 dB FS; VDD_CP* = 1.95 V 0.50 0.59

0.64 Vrms output

Voltage

32 Ω load f = 1.02 kHz, 0 dB FS; VDD_CP* = 1.95 V 0.96 0.99

1.00 Vrms

Output load 13.0 16/32 -

Ω

Disabled output impedance

Measured externally, with amplifier disabled 1.0 - -

MΩ

NOTE

1. The VDD_CP is internal Voltage of module.

3.12.3 Earpiece

Class AB earpiece driver supports 10.67 Ω, 16 Ω, 32 Ω, and up to 50 KΩ loads. Its typical output power at

1.02 KHz, 6 dB gain, and THD + N ≤ 1% is:

 119 mW with 32 Ω loads

 243 mW with 16 Ω loads

 320 mW with 10.67 Ω loads www.simcom.com 48 / 88

SIM8905 Series Hardware Design V1.07

Close to earpiece

10pF 33pF

10pF

EAR_P

10pF 33pF

10pF

EAR_M

Module

10pF 33pF

10pF

Route as differential pair

& shielded by GND

Figure 23: Earpiece reference circuit

Table 15: Earpiece output performance specifications

33pF

ESD

33pF

33pF

ESD

Parameter Test conditions

Output power

Min Typ Max Units

32 Ω load f = 1.02 kHz, 6 dB gain THD+N < 1% 120.0 124.5 -

16 Ω load f = 1.02 kHz, 6 dB gain THD+N < 1% 235.0 243.0 - mW mW

Full-scale output

6 dB gain mode f = 1.02 kHz

Voltage

Output load

1.5 dB gain mode f = 1.02 kHz

1.8

1.0

2.0

1.2

10.7 32

2.1

1.3

-

Vrms

Vrms

Ω

Disabled output impedance

Measured externally, amplifier disabled 1.0 - -

MΩ

3.12.4 Speaker

Class-D mono differential loud speaker driver supports 4

Ω and 8 Ω loads. The driver is powered from VBAT, and does not support external 5 V Boost Option. Its typical output power at 1.02 KHz, 12 dB gain, and THD

+ N ≤ 1% is:

 950 mW with 8 Ω loads, VDD_SPKR=VBAT= 4.2 V

 692 mW with 8 Ω loads, VDD_SPKR=VBAT= 3.6 V

 1063 mW with 4 Ω loads, VDD_SPKR=VBAT= 3.6 V www.simcom.com 49 / 88

SIM8905 Series Hardware Design V1.07

Close to speaker

10pF 33pF

33pF

ESD

10pF

SPK1P

10pF 33pF

10pF 33pF

SPK1N

Module

10pF 33pF

Route as differential pair

& shielded by GND

10pF 33pF

ESD

Figure 24: Speaker reference circuit

Table 16: speaker driver output performance specifications

Parameter

Output power (Pout)

(f = 1 kHz, gain = 12 dB, THD+N ≤ 1%)

Test conditions

15 μH + 8 Ω + 15 μH, Vdd = 3.6 V

15 μH + 4 Ω + 15 μH, Vdd = 3.6 V

15 μH + 8 Ω + 15 μH, Vdd = 3.8 V

15 μH + 8 Ω + 15 μH, Vdd = 4.2 V

1 W Pout, VDD_SPKR = 4.2 V

THD+N

(1 kHz)

Efficiency

（ Vdd = 3.7 V ） output impedance

Shutdown

Turn on time

800 mW Pout, VDD_SPKR = 4.2 V

600 mW Pout, VDD_SPKR = 3.8 V

500 mW Pout, VDD_SPKR = 3.6 V

500 mW Pout, 15 μH + 8 Ω + 15 μH

1 W Pout, 15 μH + 4 Ω + 15 μH

Disabled current

Min

-

-

-

-

584

862

662

819

82.0

73.0

25

-

-

Typ

84.0

78.0

-

0.1

0.2

631

953

710

879

-85.0

-75.0

-75.0

-76.0

Max Units

-

-

-

1.0

10.0

-

-

-

-

-75.0 dB

-45.0 dB

-70.0 dB

-71.0 dB

%

% kΩ

µA ms mW mW mW mW

3.12.5 Microphone bias

SIM8905 provides two microphone bias outputs: MIC_BIAS1and MIC_BIAS2. The microphone bias cannot be used for ECM-type microphone. MIC_BIAS1and MIC_BIAS2 could be used for External MEMS microphone as power supply.

The microphone bias output performance specifications are shown in the following table: www.simcom.com 50 / 88

SIM8905 Series Hardware Design V1.07

Table 17: Microphone bias output performance specifications

Parameter Test conditions Min Typ Max Units

Output voltage

Output voltage error

No load

No load

1.60 - 2.85 V

-3.00 0.00 3.00 %

Output current

Output switch to ground

2 microphone loads of 1.0 to 1.5 mA each 2.0

On resistance

Sink current

0.1 µF bypass

-

3.0

-

2.0 -

-

20

- mA

Ω mA

0.0 2.0 4.0 µVrms Output noise at 20 Hz at 200 Hz to 1 kHz

PSRR-Power supply at 5 kHz rejection ratio at 10 kHz at 20 kHz

80

80

80

80

75

-

-

-

-

-

-

-

-

-

- dB dB dB dB dB

Output capacitor value

［ 2 ］

External bypass mode ［ 1 ］ 0.1 0.1 0.5 µF

3.13 USIM Interface

SIM8905 supports dual cards dual standby, and card presence detection.

NOTE

1. The standard software provided by SIMCom only supports single USIM1 card configuration.

Table 18: USIM interface pin definitions

Pin Name

USIM2_DET

USIM2_RST

USIM2_CLK

USIM2_DAT

USIM2_VDD

USIM1_DET

USIM1_RST

USIM1_CLK

USIM1_DAT

USIM1_VDD

Pin#

17

18

19

20

21

22

23

24

25

26

Type

P

I

O

I

O

O

I/O

O

I/O

P

Description

USIM2 presence detection

USIM2 reset

USIM2 clock

USIM2 data

LDO 15 output for USIM2, 1.8V/2.95V

USIM1 presence detection

USIM1 reset

USIM1 clock

USIM1 data

LDO 14 output for USIM1, 1.8V/2.95V www.simcom.com 51 / 88

SIM8905 Series Hardware Design V1.07

Module

LDO5_1V8

USIM_VDD

USIM_RST

SUIM_CLK

USIM_DET

USIM_DAT

100K

22R

22R

22R

22pF

USIM Card

VCC

RST

CLK

DET

GND

VPP

I/O

COM

220nF

TVS

C<30pF

Figure 25: USIM card reference circuit

NOTE

1. USIM_DAT has been pulled up with a 10kohm resistor to USIM_VDD in module.

2. A 220nF shut capacitor on USIM_VDD is used to reduce interference.

3.14 ADC

SIM8905 provides one 16bits ADC. Its performance parameters are shown as the following table.

Table 19: ADC performance parameters

Parameter

Input voltage range

Test conditions

Programmable

Resolution

Analog input bandwidth

Sample rate

INL

XO/8

15-bit output

DNL

Offset error

Gain error

15-bit output

Relative to full-scale

Relative to full-scale

Min Typ Max

-

-

-

-

-

0.1

0.3

-

-

-

-

-

-

-

16

100

2.4

-

1.7

4.5

-

-

-

±8

±4

±1

±1

Units

V bits kHz

MHz

LSB

LSB

%

% www.simcom.com 52 / 88

SIM8905 Series Hardware Design V1.07

3.15 Vibrator

SIM8905 supports silent incoming-call alarms with its vibration motor driver. The vibration driver is a programmable voltage output that is referenced to VBAT; when off, its output voltage is VBAT. The motor is connected between VBAT and the VIB_DRV_N pin. The programmable motor voltage ranges from 1.2 to

3.1 V in 100 mV steps.

VBAT

1uF

Module

Vibrator

VIB_DRV

0R

Figure 26: Vibrator reference circuit

3.16 Antenna Interface

SIM8905 provides four antenna interfaces including MAIN antenna, DRX antenna, GNSS antenna, and

WiFi/BT antenna. To ensure good RF performance, users should meet the following requirements:

 Keep the RF traces at 50 Ω .

 Maintain a complete and continuous reference ground plane from antenna pin to the RF connector.

 The RF traces should be away from any other noisy traces.

 Keep the RF traces as short as possible.

3.16.1 MAIN Antenna reference circuit

The recommended circuit is shown as below: www.simcom.com 53 / 88

SIM8905 Series Hardware Design V1.07

MAIN ANT

GND

ANT_MAIN

GND

86

87

88

RF connector

(optional)

Module

Matching circuit

C1

R1

C2

Figure 27: MAIN antenna recommended circuit

R1, C1 and C2 are antenna matching components in Figure 27, the value of these components are

determined according to the antenna tuning results. By default, R1 is 0 Ω , C1 and C2 are reserved. The RF

connector in Figure 27 is used to ensure the accuracy and convenience of the conduction testing, so

SIMCOM suggest keeping it. If considering Low-Cost BOM, user can cancel the connector.

3.16.2 DRX Antenna reference circuit

The recommended circuit is shown as below:

Diversity ANT

GND

ANT_DRX

GND

130

131

132

RF connector

(optional)

Matching circuit

C1

R1

C2

Module

Figure 28: DRX antenna recommended circuit

R1, C1 and C2 are antenna matching components in Figure 28, the value of these components are

determined according to the antenna tuning results. By default, R1 is 0Ω, C1 and C2 are reserved. The RF

connector in Figure 28 is used to ensure the accuracy and convenience of the conduction testing, so

www.simcom.com 54 / 88

SIM8905 Series Hardware Design V1.07

SIMCOM suggest keeping it. If considering Low-Cost BOM, user can cancel the connector.

3.16.3

GNSS Antenna reference circuit

The recommended circuit is shown as below:

GNSS Passive

ANT

GND

ANT_GNSS

GND

120

121

122

RF connector

(optional)

Matching circuit

C1

R1

C2

Module

Figure 29: GNSS antenna recommended circuit

R1, C1 and C2 are antenna matching components in Figure 29, the value of these components are

determined according to the antenna tuning results. By default, R1 is 0Ω, C1 and C2 are reserved. The RF

connector in Figure 29 is used to ensure the accuracy and convenience of the conduction testing, so

SIMCOM suggest keeping it. If considering Low-Cost BOM, user can cancel the connector.

The module has internal LAN, so there is no need for external active antenna. But if the antenna is far away the module and need a long cable to connect, users can use external active antenna, the recommended

circuit is shown as Figure 30:

GNSS Active ANT

GND 120

ANT_GNSS 121

GND 122

RF connector

(optional)

Module

Attenuator C1

47nH

10ohm

VDD

Figure 30: GNSS active antenna circuit www.simcom.com 55 / 88

SIM8905 Series Hardware Design V1.07

The attenuator in Figure 30 must be added as required and attenuation value is determined according to

the active antenna gain. Normally, the relationship between the attenuation value and the gain satisfies the following formula:

Antenna gain = Attenuation value + Cable Losses

In Figure 30, the VDD is used to provide voltage to the external active antenna and its value should be

taken according to antenna characteristic; C1 is used for DC blocking and its value is 33pF by default.; the

RF connector is used to ensure the accuracy and convenience of the conduction testing, if considering

LOW-Cost BOM, users can cancel it.

3.16.4 WiFi/BT Antenna reference circuit

The recommended circuit is shown as below:

WIFI/BT_ ANT

GND

ANT_WIFI/BT

GND

76

77

78

RF connector

(optional)

Module

Matching circuit

C1

R1

C2

Figure 31: WIFI/BT antenna recommended circuit

R1, C1 and C2 are antenna matching components in Figure 31, the value of these components are

determined according to the antenna tuning results. By default, R1 is 0Ω, C1 and C2 are reserved. The RF

connector in Figure 31 is used to ensure the accuracy and convenience of the conduction testing, so

SIMCOM suggest keeping it. If considering Low-Cost BOM, user can cancel the connector.

3.16.5 GSM / CDMA 1X / UMTS / LTE layout guidance

The characteristic impedance of RF signals should be controlled at 50 ohm. In general, the impedance of

RF signal is determined by the Permittivity (ER) of PCB material, line width (W), ground clearance (S), height of reference ground plane (H) and other factors.

Microstrip line and coplanar waveguide are usually used to control the characteristic impedance of RF www.simcom.com 56 / 88

SIM8905 Series Hardware Design V1.07 wiring. The following illustrations show the structure design of microstrip line and coplanar waveguide.

 Microstrip line structure

2W 2W

Layer1

Prepreg

Layer2

H

W

Figure 32: Two layer PCB microstrip structure

Table 20: Example of impedance control of microstrip line structure

PCB thickness

1mm

1.6mm

Permittivity

(ER)

4.2

4.2

Line thickness

Layer

Reference plane

0.035mm Layer1 Layer2

0.035mm Layer1 Layer2

Target impedance

50 ohm

50 ohm

 Coplanar waveguide (CPW) structure

Expected linewidth

W

1.7mm (67 mil)

3mm (118 mil)

S S

Layer1

Prepreg

Layer2

H

W

Figure 33: Two layer PCB coplanar waveguide structure

Table 21: Example of impedance control of coplanar waveguide structure

PCB thickness

Permittivity

(ER)

1mm

1.6mm

4.2

4.2

Line thickness

0.035mm

0.035mm

Layer

Layer

1

Layer

1

Reference plane

Target impedance

Layer2 50 ohm

Layer2 50 ohm

Expected gap Expected to ground S linewidth W

0.65mm 0.2mm

(25.6 mil) (7.8 mil)

0.65mm

(25.6 mil)

0.15mm

(5.9 mil) www.simcom.com 57 / 88

SIM8905 Series Hardware Design V1.07

Four layer PCB coplanar waveguide structure 1# is shown in following figure. The third layer is reference layer.

S W S

Layer1

Prepreg

Layer2

Prepreg

Layer3

Prepreg

Layer4

H

2W W 2W

Figure 34: Four layer PCB coplanar waveguide structure 1#

Four layer PCB coplanar waveguide structure 2# is shown in following figure. The fourth layer is reference layer.

S W S

Layer1

Prepreg

Layer2

Prepreg

Layer3

Prepreg

Layer4

H

2W W 2W

Figure 35: Four layer PCB coplanar waveguide structure 2#

3.16.6 Antenna Requirement

The following table shows the requirements on main antenna, Rx-diversity antenna and GNSS antenna. www.simcom.com 58 / 88

SIM8905 Series Hardware Design V1.07

Table 22: Antenna Requirement

Antenna

GSM/WCDMA/TD-SCDMA/LTE

Wi-Fi/BT

GNSS

Requirements

VSWR: ≤ 2

Gain (dBi): 1

Max Input Power (W): 50

Input Impedance (ohm): 50

Polarization Type: Vertical

Cable Insertion Loss: < 1dB

(GSM850/EGSM900, WCDMA B5/B8, CDMA BC0, LTE

B5/B8/B12/B17/ B20)

Cable Insertion Loss: < 1.5dB

(DCS1800/PCS1900, WCDMA B1/B2/B3/B4,

TD-SCDMAB34/B39, LTE B1/B2/B3/B4/B39)

Cable insertion loss < 2dB (LTE B7/B38/B40/B41)

VSWR: ≤ 2

Gain (dBi): 1

Max Input Power (W): 50

Input Impedance (ohm): 50

Polarization Type: Vertical

Cable Insertion Loss: < 1dB

Frequency range: 1565 - 1607MHz

Polarization: RHCP or linear

VSWR: < 2 (Typ.)

Passive antenna gain: > 0dBi

Active antenna noise figure: < 1.5dB

Active antenna gain: > -2dBi

Active antenna embedded LNA gain: 20dB (Typ.)

Active antenna total gain: > 18dBi (Typ.)

3.16.7 Install the Antenna with RF Connector

The recommended RF connector is HIROSE UF.L-R-SMT. The antenna installation with RF connector is shown in following figure. www.simcom.com 59 / 88

SIM8905 Series Hardware Design V1.07

Figure 36: Dimensions of the UF.L-R-SMT Connector (Unit: mm) www.simcom.com 60 / 88

SIM8905 Series Hardware Design V1.07

4. PCB Layout

This section provides PCB layout guidelines for SIM8905 users to ensure their production against lots of issues, and achieve the optimum performance.

4.1 Stack-up Options

At least, 4-layer through-hole PCB should be chosen for good impedance control and signal shielding.

4.2 General Placement Guidelines

 Locate SIM8905 module in the center of PCB, rather than in the corner.

 Digital devices and traces should not be placed near sensitive signals like RF and clock.

 Keep SPKR and MIC away from sensitive RF lines.

4.3 PCB Layout Guideline Details

4.3.1 RF Trace

 RF connector should be placed close to the module’s antenna pin.

 Antenna matching circuit should be placed close to the antenna.

 Keep the RF traces at 50 Ω .

 Maintain a complete and continuous reference ground plane from antenna pin to the RF connector.

 The RF traces should be far away from any other noisy traces.

 Keep the RF traces as short as possible.

 If using a coaxial RF cable to connect the antenna, please avoid spanning on USIM cards, power circuits and high-speed digital circuits to minimize the impact of each other.

4.3.2 Power/GND

 Both VBAT and return path should be as short and wide as possible to minimize the IR drop www.simcom.com 61 / 88

SIM8905 Series Hardware Design V1.07

Pin#

58

59

60

61

52

53

54

55

56

57

63

64

 The VBAT current should go through Zener diode, capacitors, then VBAT pins

 Must have a solid ground plane throughout the board as the primary reference plane for most signals

4.3.3 USIM Card

 Ensure USIM card holder is far way from antenna or RF signal

 ESD component and bypass caps should be placed closed to USIM Card

 USIM card signals should be far away from other high-speed signal

4.3.4 MIPI_DSI/CSI

 Protect MIPI_DSI/CSI signals from noisy signals (clocks, SMPS, etc.)

 Differential pairs, 100 Ω nominal, ±10%

 Total routing length < 305 mm

 Intra-pair length matching < 5 ps (0.67 mm)

 Inter-pair length matching < 10 ps (1.3 mm)

 Lane-to-lane trace spacing = 3x line width

 Spacing to all other signals = 4x line width

 Maintain a solid ground reference for clocks to provide a low-impedance path for return currents

 Each trace needs to be next to a ground plane

 Minimize the number of via on the trace

Refer to the following table for the length of MIPI traces inside the module.

Table 23: Length of MIPI traces inside the module

Net Name

MIPI_DSI_CLK_M

MIPI_DSI_CLK_P

MIPI_DSI_LANE0M

MIPI_DSI_LANE0P

MIPI_DSI_LANE1M

MIPI_DSI_LANE1P

MIPI_DSI_LANE2M

MIPI_DSI_LANE2P

MIPI_DSI_LANE3M

MIPI_DSI_LANE3P

MIPI_CSI0_CLK_M

MIPI_CSI0_CLK_P

Length(mm)

8.08

9.03

9.04

8.73

9.29

9.10

8.69

8.95

9.10

9.85

14.04

13.79 www.simcom.com 62 / 88

SIM8905 Series Hardware Design V1.07

70

71

72

73

65

66

67

68

MIPI_CSI0_LN0_M

MIPI_CSI0_LN0_P

MIPI_CSI0_LN1_M

MIPI_CSI0_LN1_P

MIPI_CSI1_CLK_M

MIPI_CSI1_CLK_P

MIPI_CSI1_LN0_M

MIPI_CSI1_LN0_P

13.27

13.23

13.96

14.49

17.21

17.69

16.34

17.25

4.3.5 USB

 90 Ω differential, ± 10% trace impedance

 Differential data pair matching < 6.6 mm (50 ps)

 External components should be located near the USB connector.

 Should be routed away from sensitive circuits and signals.

 If there are test points, place them on the trace to keep branches as short as possible

 If USB connector is used as the charger input, USB_VBUS node must be routed to the module using extremely wide traces or sub planes.

Refer to the following table for the length of USB traces inside the module.

Table 24: Length of USB traces inside the module

Pin#

13

14

Net Name

USB_DM

USB_DP

4.3.6 SDC Signal

 Protect other sensitive signals/circuits from SDC corruption.

 Protect SDC signals from noisy signals (clocks, SMPS, etc.).

 Up to 200 MHz clock rate

 50 Ω nominal, ±10% trace impedance

 CLK to DATA/CMD length matching < 1 mm

 30–

35 Ω termination resistor on clock lines near the module

 Total routing length < 50 mm recommended

 Spacing to all other signals = 2x line width

 Bus capacitance < 15 pF

Refer to the following table for the length of SD traces inside the module.

Length(mm)

30.58

30.22 www.simcom.com 63 / 88

SIM8905 Series Hardware Design V1.07

Table 25: Length of SD traces inside the module

Pin#

39

40

41

42

43

44

Net Name

SD_CLK

SD_CMD

SD_DATA0

SD_DATA1

SD_DATA2

SD_DATA3

Length(mm)

14.24

15.19

14.87

13.63

12.90

13.05

4.3.7 Audio

Analog input

 4 to 5 mil trace widths; 4 to 5 mil spacing between traces

 Differential route for MIC1P with GND_MIC and MIC2P with GND_MIC;

 Isolate from noise sources, such as antenna, RF signals, SMPS, clocks, and other digital signals with fast transients

 Analog output

 Coplanar ground fill on both sides (of traces or pair as appropriate); in between ground planes – grounds above and below

 Isolate from noise sources such as antenna, RF signals, SMPS, clocks, and other digital signals with fast transients.

 EAR output signal – route as differential pair with 10 mil trace widths.

 SPK output signals – route as differential pair with 20 mil trace widths with 8

Ω load and 25 mil trace widths with 4

Ω load

 HPH output signals – not a differential pair; 10 mil trace widths for HPH_L and HPH_R; 15 mil trace widths for HPH_GND

 Connect HPH_GND to the ground pin of the jack connector and route HPH_GND in between HPH_L and HPH_R for best crosstalk minimization www.simcom.com 64 / 88

SIM8905 Series Hardware Design V1.07

5. Electrical and Reliability

5.1 Absolute Maximum Ratings

Absolute maximum ratings reflect the stress levels that, if exceeded, may cause permanent damage to the device. Functionality and reliability are only guaranteed within the operating conditions.

Table 26: Absolute maximum ratings

Parameter

VBAT

VBUS

VRTC

Min

-0.3

-0.3

-

5.2 Temperature Range

Max

5

7

3.5

Unit

V

V

V

Table 27: Temperature range

Parameter

Operating temperature

Storage temperature

5.3 Operating Voltage

Table 28: Operating voltage

Parameter

VBAT

VBUS

VRTC

Min

-35

-40

Min

3.4

4.35

2.0

Typ

25

Typ

3.9

5

3.0

Max

+75

+90

Unit

℃

℃

Max

4.4

5.5

3.25

Unit

V

V

V www.simcom.com 65 / 88

SIM8905 Series Hardware Design V1.07

5.4 Digital-logic Characteristics

Table 29: 1.8 V digital I/O characteristics

Parameter Description

V

IH

V

IL

V

OH

V

OL

High-level input voltage

Low-level input voltage

High-level output voltage

Low-level output voltage

Min

1.17

-

1.35

-

Table 30: USIM interface characteristics (USIM_VDD=1.8V/2.95V)

Typ

-

-

-

-

Parameter Description

V

IH

V

IL

V

OH

V

OL

Min Typ

High-level input voltage

Low-level input voltage

0.7* USIM_VDD -

-0.3 -

High-level output voltage 0.8*USIM_VDD -

Low-level output voltage 0 -

Table 31: SD interface characteristics (SD_LDO11 =1.8V)

Max

-

0.63

-

0.45

Max

Unit

V

V

V

V

Unit

USIM_VDD+0.3 V

0.2* USIM_VDD V

USIM_VDD

0.4

V

V

Parameter Description

V

IH

V

IL

V

OH

V

OL

High-level input voltage

Low-level input voltage

High-level output voltage

Low-level output voltage

Min

1.27

-0.3

1.4

0

Table 32: SD interface characteristics (SD_LDO11 =2.95V)

Typ

-

-

-

-

Max

2

0.58

-

0.45

Unit

V

V

V

V

Parameter Description

V

IH

V

IL

V

OH

V

OL

Min

Low-level input voltage -0.3

Low-level output voltage 0

Typ Max

High-level input voltage 0.625* SD_LDO11 -

-

High-level output voltage 0.75* SD_LDO11 -

-

SD_LDO11+0.3

Unit

V

0.25* SD_LDO11 V

SD_LDO11 V

0.125* SD_LDO11 V www.simcom.com 66 / 88

SIM8905 Series Hardware Design V1.07

5.5 PWRKEY Characteristics

Table 33: PWRKEY characteristics

Parameter Description

V

IH

V

IL

High-level input voltage

Low-level input voltage

5.6 VRTC Characteristics

Min

1.4

-

Typ

-

-

Table 34: VRTC characteristic

Parameter Description

VRTC

-IN

I

RTC-IN

VRTC

-OUT

I

RTC-OUT

VRTC input voltage

VRTC current consumption

VRTC output voltage

VRTC output current

5.7 Current Consumption (VBAT=3.9V)

Min

2.0

-

2.5

-

Table 35: Current consumption

Parameter

Leakage current

Standby current

Conditions

Off mode

Flight mode

GSM:

BS-PA-MFRMS=9

BS-PA-MFRMS=5

BS-PA-MFRMS=2

WCDMA @DRX=8

CDMA 1X @max slot=1~7

EVDO @max slot=1~7

TD-SCDMA @DRX=7

LTE-FDD @standby 1.28s

LTE-TDD @standby 1.28s

Min

Typ

3.0

5

3.1

Typ

3.00

1.7

2.25

2.11

2.56

20

1.22

1.65

1.85

3.00

2.48

Max

-

0.6

Max

3.25

10

3.2

2

Max

Unit

V

V

Unit

V uA

V mA

Unit mA mA mA mA mA uA mA mA mA mA mA www.simcom.com 67 / 88

GSM Voice Call

GPRS Data

GSM850 @PCL5

EGSM900 @PCL5

WCDMA Voice Call

EVDO Voice Call

DCS1800 @PCL0

Band 1 @max power

Band 5 @max power

Band 8 @max power

BC0 @max power

GSM850 (1UL/4DL) @PCL5

GSM850 (2UL/3DL) @PCL5

GSM850 (4UL/1DL) @PCL5

GSM900(1UL/4DL) @PCL5

GSM900 (2UL/3DL) @PCL5

GSM900 (4UL/1DL) @PCL5

DCS1800 (1UL/4DL) @PCL5

DCS1800 (2UL/3DL) @PCL5

DCS1800 (4UL/1DL) @PCL5

EDGE Data

GSM850 (1UL/4DL) @PCL8

GSM850 (2UL/3DL) @PCL8

GSM850 (4UL/1DL) @PCL8

GSM900(1UL/4DL) @PCL8

GSM900 (2UL/3DL) @PCL8

GSM900 (4UL/1DL) @PCL8

DCS1800 (1UL/4DL) @PCL2

DCS1800 (2UL/3DL) @PCL2

CDMA Data

LTE Data

Peak current

DCS1800 (4UL/1DL) @PCL2

BC0 @max power

FDD Band1 @max power

FDD Band3 @max power

FDD Band5 @max power

FDD Band8 @max power

TDD Band38 @max power

TDD Band39 @max power

TDD Band40 @max power

TDD Band41 @max power

242

346

150

240

381

467

715

712

497

184

291

476

163

247

411

159

678

610

436

361

363

369

467

510

236

385

723

228

372

259

248

209

460

452

SIM8905 Series Hardware Design V1.07 mA mA mA mA mA mA mA mA mA mA mA mA mA mA mA mA mA mA

A mA mA mA mA mA mA mA mA mA mA mA mA mA mA mA mA

3.0

www.simcom.com 68 / 88

SIM8905 Series Hardware Design V1.07

5.8 Electro-Static Discharge

Electrostatic discharge (ESD) occurs naturally in laboratory and factory environments. An established high-voltage potential is always at risk of discharging to a lower potential. If this discharge path is through a semiconductor device, it may result in destructive damage.

SIM8905 must be handled according to the ESD Association standard: ANSI/ESD S20.20-1999, Protection of Electrical and Electronic Parts, Assemblies, and Equipment.

Table 36: ESD performance parameters （ Temperature: 25 ℃ , Humidity: 45% ）

Pin

VBAT

GND

Antenna

PWRKEY

Contact discharge

± 5KV

± 5KV

± 5KV

± 4KV

5.9 Module Operating Frequencies

Air discharge

± 10 KV

± 12KV

± 10KV

± 6KV

Table 37: Module operating frequencies

Frequency

GSM850

EGSM900

DCS1800

PCS1900

WCDMA B1

WCDMA B2

Receive

869-894MHz

925-960MHz

1805-1880MHz

1930-1990MHz

2110-2170 MHz

1930-1990MHz

WCDMA B5 869-894MHz

WCDMA B8 925-960MHz

CDMA BC0 869-894MHz

TDSCDMA B39 1880-1920 MHz

TDSCDMA B34 2010-2025 MHz

LTE B1 2110-2170 MHz

LTE B3 1805-1880 MHz

LTE B5 869-894 MHz

Transmit

824-849MHz

880-915MHz

1710-1785MHz

1850-1910MHz

1920-1980 MHz

1850-1910MHz

824-849MHz

880-915 MHz

824-849MHz

1880-1920MHz

2010-2025MHz

1920-1980 MHz

1710-1785 MHz

824-849MHz

Physical channel

128-251

0-124, 975-1023

512-885

512-810

TX: 9612-9888

RX: 10562-10838

TX: 9262-9538

RX: 9662-9938

TX: 4132-4233

RX: 4357-4458

TX: 2712-2863

RX: 2937-3088

1-799 ;991-1023

9400-9600

10054-10121

TX: 18000-18599

RX: 0-599

TX: 19200-19949

RX: 1200-1949

TX: 20400-20649

RX: 2400-2649 www.simcom.com 69 / 88

SIM8905 Series Hardware Design V1.07

LTE B7

LTE B8

LTE B38

LTE B39

LTE B40

LTE B41

[1]

2620-2690 MHz

925-960 MHz

2570-2620 MHz

1880-1920 MHz

2300-2400 MHz

2555-2655 MHz

2500-2570 MHz

880-915 MHz

2570-2620 MHz

1880-1920 MHz

2300-2400 MHz

2555-2655MHz

TX: 20750-21449

RX: 2750-3449

TX: 21450-21799

RX: 3450-3799

37750-38249

38250-38649

38650-39649

40240-41240

NOTE

SIM8905’s TDD-LTE B41 bandwidth is 100MHz (2555 ~ 2655 MHz), the channel is 40240 ~ 41240.

5.10 Module Output power

Table 38: Conducted transmission power

Frequency Power

GSM850

E-GSM900

DCS1800

PCS1900

33dBm ±2dB

33dBm ±2dB

30dBm ±2dB

30dBm ±2dB

E-GSM900 (8-PSK) 27dBm ±3dB

DCS1800 (8-PSK) 26dBm +3/-4dB

WCDMA B1 24dBm +1/-3dB

WCDMA B2

WCDMA B5

WCDMA B8

CDMA BC0

TDSCDMA B34

TDSCDMA B39

LTE-FDD B1

LTE-FDD B3

24dBm +1/-3dB

24dBm +1/-3dB

24dBm + 1/-3dB

24dBm + 1/-1dB

24dBm + 1/-3dB

24dBm + 1/-3dB

23dBm +/-2.7dB

23dBm +/-2.7dB

LTE-FDD B5

LTE-FDD B7

LTE-FDD B8

LTE-FDD B20

LTE-TDD B38

LTE-TDD B39

23dBm +/-2.7dB

23dBm +/-2.7dB

23dBm +/-2.7dB

23dBm +/-2.7dB

23dBm +/-2.7dB

23dBm +/-2.7dB

Min.

5dBm ± 5dB

5dBm ± 5dB

0dBm ± 5dB

0dBm ± 5dB

5dBm ± 5dB

0dBm ±5dB

<-50dBm

<-50dBm

<-50dBm

<-50dBm

<-50dBm

<-50dBm

<-50dBm

<-40dBm

<-40dBm

<-40dBm

<-40dBm

<-40dBm

<-40dBm

<-40dBm

<-40dBm www.simcom.com 70 / 88

SIM8905 Series Hardware Design V1.07

LTE-TDD B40

LTE-TDD B41

23dBm +/-2.7dB

23dBm +/-2.7dB

5.11 Module Receiving Sensitivity

<-40dBm

<-40dBm

Table 39: Conducted receiving sensitivity

Band Receiving sensitivity （ Typ ）

GSM850

EGSM900

DCS1800

PCS1900

WCDMA B1

WCDMA B2

WCDMA B5

WCDMA B8

< -108dBm

< -108dBm

< -108dBm

< -108dBm

<-109 dBm

<-109 dBm

<-109 dBm

<-109 dBm

CDMA BC0 <-109 dBm

TDSCDMA B34 <-110 dBm

TDSCDMA B39 <-110 dBm

LTE FDD/TDD Table 38

Receiving sensitivity

3GPP standard

3GPP standard

3GPP standard

3GPP standard

3GPP standard

3GPP standard

3GPP standard

3GPP standard

3GPP standard

3GPP standard

3GPP standard

3GPP standard

（ Max ）

Table 40: Reference sensitivity QPSk PREFSENS (LTE)

6

7

8

9

2

3

4

5

10

11

12

13

14

E-UTRA

Band number

1

1.4 MHz 3 MHz 5 MHz 10 MHz 15 MHz 20 MHz

-

-102.7

-101.7

-104.7

-103.2

-

-

-102.2

-

-

-

-101.7

-

-99.7

-98.7

-101.7

-100.2

-

-

-99.2

-

-

-

-98.7

-

-100

-98

-97

-100

-98

-100

-98

-97

-99

-100

-100

-97

-97

-97

-97

-95

-94

-97

-95

-97

-95

-94

-96

-97

-97

-94

-94

-94

-95.2

-93.2

-92.2

-95.2

-93.2

-94.2

-95.2

-94

-92

-91

-94

-92

-93

-94

Duplex mode

FDD

FDD

FDD

FDD

FDD

FDD

FDD

FDD

FDD

FDD

FDD

FDD

FDD

FDD www.simcom.com 71 / 88

35

36

37

38

24

25

33

34

39

40

41

42

43

17

18

19

20

21

22

23

-

-

-

-

-

-

-

-101.2

-

-

-106.2

-106.2

-

-

-

-104.7

-

-

-

-

-

-

-

-98.2

-

-

-102.2

-102.2

-

-

-

-101.7

-100

-96.5

-100

-100

-100

-100

-100

-100

-97

-100

-100

-97

-100

-97

-100

-100

-100

-99

-99

-99

5.12 WIFI Main RF Characteristics

Table 41: WIFI main RF Characteristics

Transmission performance

Output power

EVM

Receiving performance

Receiving sensitivity

802.11B

17

20%

802.11B

-89

-97

-97

-96

-96

-96

-97

-97

-97

-97

-97

-93.5

-97

-97

-94

-97

-97

-94

-97

-94

-97

SIM8905 Series Hardware Design V1.07

-91.7

-95.2

-95.2

-95.2

-95.2

-95.2

-95.2

-95.2

-95.2

-91.2

-95.2

-92.2

-95.2

-95.2

-94.2

-94.2

-94.2

-94

-94

-93

-93

-93

-94

-94

-94

-94

-90.5

-94

-

-

-

-90

-91

FDD

FDD

TDD

TDD

TDD

TDD

TDD

TDD

FDD

FDD

FDD

FDD

FDD

FDD

FDD

TDD

TDD

TDD

TDD

TDD

802.11G 802.11N

15 12

-25 -27 dBm dB

802.11G 802.11N

-74.5 -72.5 dBm www.simcom.com 72 / 88

SIM8905 Series Hardware Design V1.07

5.13 BT Main RF Characteristics

Table 42: BT Main RF Characteristics

Transmission performance

Output power

Receiving performance

Receiving sensitivity

DH5

9

DH5

-90

5.14 GNSS Main RF Characteristics

Table 43: GNSS Main RF Characteristics

Receiver type

CNo

Sensitivity

TTFF

GPS,GLANOSS,BEIDOU

39dB/Hz@-130dBm

Tracking & Navigation

Reacquisition

Cold start

Cold start

Warm start

Hot start

2DH5

7

2DH5

-80

-160dBm

-156dBm

-148dBm

<35s

<15s

<5s

3DH5

7

3DH5

-80 dBm dBm www.simcom.com 73 / 88

6. Manufacturing

6.1 Top and Bottom View of SIM8905

SIM8905 Series Hardware Design V1.07

Figure 37: Top and bottom view of SIM8905 www.simcom.com 74 / 88

SIM8905 Series Hardware Design V1.07

6.2 Typical SMT Reflow Profile

The thickness of SMT stencil shall be increased to 0.15-0.18mm.

Figure 38: Typical SMT reflow profile

NOTE

Please refer to “SIM8905_Module_SMT_Secondary_User_Guide_V1.00” for more information about the module shipping and manufacturing.

6.3 Moisture Sensitivity Level (MSL)

SIM8905 is susceptible to damage induced by absorbed moisture and high temperature. A package’s moisture-sensitivity level (MSL) indicates its ability to withstand exposure after it is removed from its shipment bag, while it is on the factory floor awaiting PCB installation. A low MSL rating is better than a high rating; a low MSL device can be exposed on the factory floor longer than a high MSL device. All pertinent

MSL ratings are summarized in the following table.

Table 44: Moisture classification level and floor life

MSL

1

Out-of-bag floor life

Unlimited

Comments

≤ +30 ℃ /85% RH www.simcom.com 75 / 88

SIM8905 Series Hardware Design V1.07

2

2a

3

4

5

5a

6

1 year

4 weeks

168 hours

72 hours

≤ +30 ℃ /60% RH

≤ +30 ℃ /60% RH

≤ +30 ℃ /60% RH

≤ +30 ℃ /60% RH

≤ +30 ℃ /60% RH 48 hours

24 hours ≤ +30 ℃ /60% RH

Mandatory bake before use. After bake, it must be reflowed within the time limit

≤ +30 ℃ /60% RH specified on the label.

The MSM8909 device samples are currently classified as MSL4 at 255 (+5, -0)°C, following the latest

IPC/JEDEC J-STD-020 standard revision for moisture-sensitivity qualification This qualification temperature

(255 (+5, -0)°C) should not be confused with the peak temperature within the recommended solder reflow profile.

6.4 Baking Requirements

It is necessary to bake modules if the prescribed time limit has been exceeded. The baking conditions are

specified in Table 42. Note that if baking is required, the devices must be transferred into trays that can be

baked to at least 125°C.

Table 45: Baking requirements

Baking conditions options Duration

40°C±5°C, <5% RH

120°C±5°C, <5% RH

192 hours

4 hours

6.5 Packing System

The SIM8905 is packaged on trays.

The production flow of module package is shown as below: www.simcom.com 76 / 88

SIM8905 Series Hardware Design V1.07

Figure 39: production flow of module package

The dimension of module tray is shown as below:

Figure 40: The dimension of module tray

Table 46: Tray information

Length （ ±3mm ）

242.0

Width

161.0

（ ±3mm ） Count of module

8 www.simcom.com 77 / 88

The dimension of small carton is shown as below:

SIM8905 Series Hardware Design V1.07

Figure 41: The dimension of small carton

Table 47: Small carton information

Length （ ±10mm ） Width （ ±10mm ） Height （ ±10mm ） Count of tray

270 180 120 8*19-2=150

The dimension of big carton is shown as below:

Figure 42: The dimension of big carton www.simcom.com 78 / 88

SIM8905 Series Hardware Design V1.07

Table 48: Big carton information

Length （ ±10mm ） Width （ ±10mm ） Height （ ±10mm ） Count of small carton

380 280 280 150*4=600 www.simcom.com 79 / 88

SIM8905 Series Hardware Design V1.07

7. List of Recommended Devices

Table 49: Recommended touch screen Controller

Model

FocalTech-FT5336GQQ

FocalTech- FT5436i

FocalTech- FT6306

FocalTech- FT6336

SYNAPTICS-S2202

Goodix-GT9 series

Goodix-GT5688

Table 50: Recommended capacitive touch screen models

Vendor

Focaltech systems Co., Ltd.

Focaltech systems Co., Ltd.

Focaltech systems Co., Ltd.

Focaltech systems Co., Ltd.

Synaptics Incorporated.

Shenzhen Goodix Technology Co., Ltd.

Shenzhen Goodix Technology Co., Ltd.

Model

FocalTech-FT5336GQQ-Truly-CT4F0694

Vendor Size

Truly Opto-electronics Ltd. 5"

FocalTech-FT5436i-Truly-CT2S0438

FocalTech-FT6336-Truly-CT1F1753-E

Truly Opto-electronics Ltd. 5"

Truly Opto-electronics Ltd. 5"

Silead-GSL2682-Top Touch-TTCT045030 Top-Touch Electronics

Co., Ltd.

SYNAPTICS-S2202-Truly-CT3G0225-V1-E Truly Opto-electronics Ltd. 4.7"

Table 51: Recommended Sensors

Type of Sensor

Accelerometer

Magnetometer

Distance and ambient light

Touch points

5

5

2

5

10

Model Vendor

Bosch-BMA222E

Bosch-BMA223

Kionix-KXTJ2-1009

AKM-AK09911

Bosch Sensortec GmbH

Bosch Sensortec GmbH

Kionix, Inc.

Asahi Kasei Corporation.

Memsic-MMC3416xPJ MEMSIC, Inc

MEMSIC-MMC3630KJ Andriod M MEMSIC, Inc ams-TMD27723T

Avago-APDS9930

Lite-On-LTR553ALS ams AG

Broadcom

Lite-On www.simcom.com 80 / 88

SIM8905 Series Hardware Design V1.07

ROHM-RPR0521RS

Table 52: Recommended Camera Sensors

Camera

Camera

Front Camera

Rear Camera

Resolution Model

Resolution

VGA

2M

5M

2M

5M

GC0310

GC0339

SP0A20

GC2355

GC2145

OV2680

OV2685

SP2508

SP2529

HI258

GC5005

AR0542

OV5670

OV5675

OV5695

S5K5E2

S5K5E8

Hi551

OV2680

GC2355

SP2508

OV5648

OV5670

S5K5E2

Hi551

SP5409

8M

HM8040

Hi842

OV8856

OV8858-R1A

OV8858

ROHM Semiconductor

Vendor

GalaxyCore Inc.

GalaxyCore Inc.

SuperPix Micro Technology Co., Ltd.

GalaxyCore Inc.

GalaxyCore Inc.

OmniVision Technology (Shanghai) Co., Ltd.

OmniVision Technology (Shanghai) Co., Ltd.

SuperPix Micro Technology Co., Ltd.

SuperPix Micro Technology Co., Ltd.

SK hynix

GalaxyCore Inc.

ON Semiconductor

OmniVision Technology (Shanghai) Co., Ltd.

OmniVision Technology (Shanghai) Co., Ltd.

OmniVision Technology (Shanghai) Co., Ltd.

Samsung Electronics Co., Ltd.

Samsung Electronics Co., Ltd.

SK hynix

OmniVision Technology (Shanghai) Co., Ltd.

GalaxyCore Inc.

SuperPix Micro Technology Co., Ltd.

OmniVision Technology (Shanghai) Co., Ltd.

OmniVision Technology (Shanghai) Co., Ltd.

Samsung Electronics Co., Ltd.

SK hynix

SuperPix Micro Technology Co., Ltd.

Himax Imaging,Inc

SK hynix

OmniVision Technology (Shanghai) Co., Ltd.

OmniVision Technology (Shanghai) Co., Ltd.

OmniVision Technology (Shanghai) Co., Ltd.

www.simcom.com 81 / 88

SIM8905 Series Hardware Design V1.07

Table 53: Recommended LCM models

Model Vendor

Resol ution

Type Size

Himax-HX8379A-Truly

Semiconductor-TFT1P6457-V1-E

Himax-HX8379C-Truly

Semiconductor-TDO-FWVGA0446G00002

Himax-HX8379C-Truly

Semiconductor-TDO-FWVGA0446G00002

Himax-HX8389B-Truly

Semiconductor-TFT540960-20-E

Truly Opto-electronics Ltd. FWVGA TFT

Truly Opto-electronics Ltd. FWVGA TFT

Truly Opto-electronics Ltd. FWVGA TFT

Truly Opto-electronics Ltd. qHD TFT

4.46"

4.46"

4.46"

4.5"

Ilitek-ILI9806E-DIJING-ART45BI2026A-1

Ilitek-ILI9881-CPT-CLAA053WD41-3XB

Novatek-NT35512-TCL-TD-TNWV4306

Shenzhen DJN Optronics

Co., Ltd.

FWVGA TFT 4.5"

Chunghwa Picture Tubes

HD

Ltd.

China Display

IPS 5.3"

Optoelectronics

WVGA TFT 4.3"

Technology Holdings limited.

Orise-OTM8018B-Truly

Semiconductor-TFT480854-11-E

Truly Opto-electronics Ltd. FWVGA TFT 4.63"

Orise-OTM8019A-DSBJ-D0400BO01 DSBJ WVGA TFT 3.97"

NOTE

If the peripheral devices selected by the customer are not listed in above tables, please contact SIMom for technical support. www.simcom.com 82 / 88

SIM8905 Series Hardware Design V1.07

A. Related Documents

[8]

[9]

[10]

[11]

[12]

Table 54: Related Documents

No.

[1]

[2]

[3]

[4]

[5]

[6]

[7]

[13]

[14]

[15]

[16]

[17]

Document name Remark

GSM 07.07

：

Digital cellular telecommunications (Phase 2+); AT command set for GSM Mobile Equipment (ME)

Support GSM 07.10 multiplexing protocol GSM 07.10

：

GSM 07.05

GSM 11.14

：

：

Digital cellular telecommunications (Phase 2+); Use of Data

Terminal Equipment – Data Circuit terminating Equipment (DTE –

DCE) interface for Short Message Service (SMS) and Cell

Broadcast Service (CBS)

Digital cellular telecommunications system (Phase 2+);

Specification of the SIM Application Toolkit for the Subscriber

Identity Module – Mobile Equipment (SIM – ME) interface

Digital cellular telecommunications system (Phase 2+);

GSM 11.11

GSM 03.38

：

：

Specification of the Subscriber Identity Module – Mobile

Equipment (SIM – ME) interface

Digital cellular telecommunications system (Phase 2+); Alphabets and language-specific information

Digital cellular telecommunications system (Phase 2); Mobile

GSM 11.10 Station (MS) conformance specification; Part 1: Conformance

3GPP TS 51.010-1

3GPP TS 34.124

3GPP TS 34.121

3GPP TS 34.123-1

3GPP TS 34.123-3

EN 301 908-02 V2.2.1

EN 301 489-24 V1.2.1 specification

Digital cellular telecommunications system (Release 5); Mobile

Station (MS) conformance specification

Electromagnetic Compatibility (EMC) for mobile terminals and ancillary equipment.

Electromagnetic Compatibility (EMC) for mobile terminals and ancillary equipment.

Technical Specification Group Radio Access Network; Terminal conformance specification; Radio transmission and reception

(FDD)

User Equipment (UE) conformance specification; Part 3: Abstract

Test Suites.

Electromagnetic compatibility and Radio spectrum Matters (ERM);

Base Stations (BS) and User Equipment (UE) for IMT-2000. Third

Generation cellular networks; Part 2: Harmonized EN for

IMT-2000, CDMA Direct Spread (UTRA FDD) (UE) covering essential requirements of article 3.2 of the R&TTE Directive

Electromagnetic compatibility and Radio Spectrum Matters

(ERM); Electromagnetic Compatibility (EMC) standard for radio equipment and services; Part 24: Specific conditions for IMT-2000

CDMA Direct Spread (UTRA) for Mobile and portable (UE) radio and ancillary equipment

IEC/EN60950-1(2001) Safety of information technology equipment (2000)

GCF-CC V3.23.1

2002/95/EC

Global Certification Forum - Certification Criteria

Directive of the European Parliament and of the Council of 27

January 2003 on the restriction of the use of certain hazardous substances in electrical and electronic equipment (RoHS) www.simcom.com 83 / 88

SIM8905 Series Hardware Design V1.07

B. Terms and Abbreviations

Table 55: Terms and abbreviations

Abbreviation

ADC

DTX

EFR

EGSM

ESD

ESR

ETS

EVDO

FDD

FR

GNSS

GPIO

CTS

DAC

DDR

DSDA

DSDS

DSP

DTE

DTR

AMR

BOM bps

BT

CDMA

CS

CSD

CSI

Description

Analog-to-Digital Converter

Adaptive Multi-Rate

Bill of materials

Bits per second

Bluetooth

Code division multiple access

Coding Scheme

Circuit Switched Data

Camera serial interface

Clear to Send

Digital-to-analog converter

Double data rate

Dual SIM dual active

Dual SIM dual standby

Digital signal processor

Data Terminal Equipment (typically computer, terminal, printer)

Data Terminal Ready

Discontinuous Transmission

Enhanced Full Rate

Enhanced GSM

Electrostatic Discharge

Effective series resistance

European Telecommunication Standard

Evolution data optimized

Frequency division duplex

Full Rate

Global navigation satellite system

General-purpose input/output www.simcom.com 84 / 88

PWM

RMS

RTC

RX

SD

SDC

SIM

SMS

PCB

PCL

PCS

PDU

RF

PM

RoHS

PPP

SMT

SPI

TDD

TE

GPRS

GPU

GSM

HR

HSPA

I2C

IMEI

ISP

Kbps

LCD

LDO

LPDDR

MIC

MIPI

PA

PBCCH

General Packet Radio Service

Graphics processing unit

Global Standard for Mobile Communications

Half Rate

High-speed packet access

Inter-integrated circuit

International Mobile Equipment Identity

Image signal processing kilobits per second

Liquid crystal display

Low dropout (linear regulator)

Low-power DDR

Microphone

Mobile industry processor interface

Power amplifier

Packet Broadcast Control Channel

Printed Circuit Board

Power Control Level

Personal Communication System, also referred to as GSM 1900

Protocol Data Unit

Radio Frequency

Power management

Restriction of hazardous substances

Point-to-point protocol

Pulse-width modulator

Root Mean Square (value)

Real-time clock

Receive Direction

Secure digital

Secure digital controller

Subscriber Identification Module

Short Message Service

Surface mount technology

Serial peripheral interface

Time Division Distortion

SIM8905 Series Hardware Design V1.07

Terminal Equipment, also referred to as DTE www.simcom.com 85 / 88

TX

UART

USIM

URC

USB

USSD

WCDMA

WCN

WLAN

SIM8905 Series Hardware Design V1.07

Transmit Direction

Universal Asynchronous Receiver & Transmitter

User identity module

Unsolicited Result Code

Universal serial bus

Unstructured Supplementary Service Data

Wideband code division multiple access

Wireless connectivity network

Wireless local area network www.simcom.com 86 / 88

SIM8905 Series Hardware Design V1.07

C. Safety Caution

Pay attention to the following safety precautions when using or maintaining any terminal or mobile phone that contains the module. Inform the users of the following security information on the terminal device.

Otherwise SIMCom will not bear any consequences resulting from the users’ not operating according to these warnings.

Table 56: Safety Caution

Marks Requirements

When in a hospital or other health care facility, observe the restrictions about the use of mobiles. Switch the cellular terminal or mobile off, medical equipment may be sensitive and not operate normally due to RF energy interference.

Switch off the cellular terminal or mobile before boarding an aircraft. Make sure it is switched off. The operation of wireless appliances in an aircraft is forbidden to prevent interference with communication systems. Forgetting to think much of these instructions may impact the flight safety, or offend local legal action, or both.

Do not operate the cellular terminal or mobile in the presence of flammable gases or fumes. Switch off the cellular terminal when you are near petrol stations, fuel depots, chemical plants or where blasting operations are in progress. Operation of any electrical equipment in potentially explosive atmospheres can constitute a safety hazard.

Your cellular terminal or mobile receives and transmits radio frequency energy while switched on. RF interference can occur if it is used close to TV sets, radios, computers or other electric equipment.

Road safety comes first! Do not use a hand-held cellular terminal or mobile when driving a vehicle, unless it is securely mounted in a holder for hands free operation. Before making a call with a hand-held terminal or mobile, park the vehicle.

GSM cellular terminals or mobiles operate over radio frequency signals and cellular networks and cannot be guaranteed to connect in all conditions, especially with a mobile fee or an invalid SIM card. While you are in this condition and need emergent help, please remember to use emergency calls. In order to make or receive calls, the cellular terminal or mobile must be switched on and in a service area with adequate cellular signal strength. www.simcom.com 87 / 88

SIM8905 Series Hardware Design V1.07

Some networks do not allow for emergency call if certain network services or phone features are in use (e.g. lock functions, fixed dialing etc.). You may have to deactivate those features before you can make an emergency call.

Also, some networks require that a valid SIM card be properly inserted in the cellular terminal or mobile. www.simcom.com 88 / 88