GPS Receiver A2235-H

A Description of Maestro’s

GPS Antenna Receiver Module A2235-H

User’s Manual

Version 0.1

Revision History

Rev. Date Description

mm-dd-yy

Written by

Checked by

Approval by

Happy wen

Name

Sam Law, Matthieu

Frank Tang, Calvin Yau

Date Signature

08-15-12

08-15-12

08-15-12

H W

S L,M

F T,C Y

V0.1 – Aug-12 User’s Manual Page 2 of 33

Disclaimer

THIS DOCUMENT CONTAINS PROPRIETARY INFORMATION OF MAESTRO

WIRELESS SOLUTIONS LIMITED. IT MAY NOT BE COPIED OR TRANSMITTED

BY ANY MEANS, PASSED TO OTHERS, OR STORED IN ANY RETRIEVAL

SYSTEM OR MEDIA, WITHOUT PRIOR CONSENT OF MAESTRO OR ITS

AUTHORIZED AGENTS.

THE INFORMATION IN THIS DOCUMENT IS, TO THE BEST OF OUR

KNOWLEDGE, ENTIRELY CORRECT. HOWEVER, MAESTRO CAN NEITHER

ACCEPT LIABILITY FOR ANY INACCURACIES, OR THE CONSEQUENCES

THEREOF, NOR FOR ANY LIABILITY ARISING FROM THE USE OR

APPLICATION OF ANY CIRCUIT, PRODUCT, OR EXAMPLE SHOWN IN THE

DOCUMENT.

THE PRODUCT (HARD- AND SOFTWARE) DESCRIBED IN THIS

DOCUMENTATION IS NOT AUTHORIZED FOR USE IN LIFE SUPPORT DEVICES

OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF MAESTRO.

THIS DOCUMENT MAY PROVIDE LINKS TO OTHER WORLD WIDE WEB SITES

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RELIANCE ON ANY SUCH CONTENT, GOODS OR SERVICES AVAILABLE ON

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MAESTRO RESERVES THE RIGHT TO CHANGE, MODIFY, OR IMPROVE THIS

DOCUMENT OR THE PRODUCT DESCRIBED HEREIN, AS SEEN FIT BY

MAESTRO WITHOUT FURTHER NOTICE.

V0.1 – Aug-12 User’s Manual Page 3 of 33

Table of Contents

1 Introduction ........................................................................................................ 6

1.1 Feature Overview.............................................................................................. 6

1.2 Characteristics Overview .................................................................................. 7

1.3 RoHS and Lead-Free Information ..................................................................... 7

1.4 Label ................................................................................................................. 8

1.5 Characteristics .................................................................................................. 9

1.5.1 GPS Characteristics ................................................................................................... 9

1.5.2 Mechanical Characteristics......................................................................................... 9

1.6 Handling Precautions ........................................................................................ 9

2 Ordering Information ....................................................................................... 10

2.1 GPS Receiver A20235-H ................................................................................ 10

2.2 Packing ........................................................................................................... 10

2.3 Additional Equipment ...................................................................................... 13

3 Quick Start ........................................................................................................ 14

3.1 Minimum Configuration ................................................................................... 14

3.2 Antenna...........................................................................................................16

3.3 Serial Port Settings ......................................................................................... 16

3.4 Improved TTFF ............................................................................................... 16

4 Mechanical Outline .......................................................................................... 17

4.1 Details Component Side A2235-H .................................................................. 17

4.2 Details Solder Side A2235-H .......................................................................... 18

5 Pin-out Information .......................................................................................... 19

5.1 Layout A2235-H .............................................................................................. 19

5.2 Description A2235-H Signals .......................................................................... 20

6 Electrical Characteristics ................................................................................ 21

6.1 Operating Conditions ...................................................................................... 21

6.2 Absolute Maximum Ratings ............................................................................ 21

6.3 DC Electrical Characteristics........................................................................... 22

7 Mounting ........................................................................................................... 23

7.1 Proposed Footprint for Soldering .................................................................... 23

7.2 PCB Design Guide .......................................................................................... 23

7.3 Recommended Profile for Reflow Soldering ................................................... 25

8 Quality and Reliability...................................................................................... 26

8.1 Environmental Conditions ............................................................................... 26

8.2 Product Qualification ....................................................................................... 26

8.3 Production Test ............................................................................................... 26

9 Applications and Hints .................................................................................... 27

9.1 Initial Module Start .......................................................................................... 27

9.2 Proper Shutdown and Power-On-Reset (POR)............................................... 27

V0.1 – Aug-12 User’s Manual Page 4 of 33

9.3 SiRFaware

TM

Support ..................................................................................... 27

9.4 Push-to-Fix Mode............................................................................................ 27

9.5 Hibernate Mode............................................................................................... 28

9.6 Extended Ephemeris....................................................................................... 28

9.7 TM_GPIO5 pin (1 pulse per second pin)......................................................... 28

10 Evaluation Kit EVA2235-H ............................................................................. 30

11 Related Information ....................................................................................... 31

11.1 Contact.......................................................................................................... 31

11.2 Related Documents....................................................................................... 31

11.3 Related Tools ................................................................................................ 31

12 List of Figures ................................................................................................ 32

13 List of Tables .................................................................................................. 33

V0.1 – Aug-12 User’s Manual Page 5 of 33

1 Introduction

A2235-H is an antenna module with SiRF Star IV ROM based chip and an on-board patch antenna (15mm x 15mm x 4mm). It is cost down version of A2035-H with reduced size and stacked up antenna architecture. In order to have easier migration for existing customers, we decided to keep same pin assignment as that of A2035-H.

Since there is RF feed point underneath the module, special PCB design is required on user’s application and therefore it can’t be stated as pin-to-pin compatible with

A2035-H. The module is capable of receiving signals from up to 48 GPS satellites and transferring them into position and timing information that can be read over a serial port.

The A2235-H is a module designed for a 3.3V environment.

1.1 Feature Overview

The A2235-H is a new module with the following outstanding features.

• Fast, responsive location experience o

High-sensitive navigation engine with tracking down to -163dBm o

48 track verification channels o

SBAS (WAAS, EGNOS, MSAS, GAGAN)

• Breakthrough micro power technology o

Requires only 50 – 500µA to maintain hot start capability

• Active jammer remover o

Removes in-band jammers up to 80dB/Hz o

Tracks up to eight CW (continuous wave) jammers

V0.1 – Aug-12 User’s Manual Page 6 of 33

1.2 Characteristics Overview

The module’s most important characteristics are:

Operable at 3.3V / 31mA (typ.) @ 1fix per second

• UART interface at CMOS level

• Small form factor of 17.78 x 16.51 mm² (0.7” x 0.65”)

• Supported range: -40°C to +85°C

• Single-sided SMT component, for reflow soldering

• RoHS compliant, lead-free

• Tape & reel packaging

• On-module patch antenna

The antenna receiver module is available as an off-the-shelf component, 100% tested and shipped in tape-and-reel packaging.

1.3 RoHS and Lead-Free Information

Maestro’s products marked with the lead-free symbol either on the module or the packaging comply with the "Directive 2002/95/EC of the European Parliament and the Council on the Restriction of Use of certain Hazardous Substances in

Electrical and Electronic Equipment" (RoHS).

V0.1 – Aug-12

All Maestro GPS receiver modules, GPS antenna receiver module and telematics units are RoHS compliant.

User’s Manual Page 7 of 33

1.4 Label

The A2235-H label (size: 12.0x 4.0 mm²) contains the following information:

Figure 1: A2235-H label

The label is placed on the side of the GPS antenna. The data matrix code holds the product type, part number, software release, hardware release, factory code, year & week of assembly and a 6-digit serial number. Due to limited space on module label, only product type, year & week of assembly and 6-digit serial number will be printed on it.

Representing Factory Product Part Software Hardware Assembly Serial location

Number of digits

(16)

Number Number Release Release Year/Week Number

XX XXXXXXX XXXX XX XX XXXX XXXXXX

2 6 4 2 2 4 6

Meaning GSL Given Given Given Given Year=12

Week=11

Increment from

000001 up to

999999

Example of MID#: GSA2235H932201011211000005

V0.1 – Aug-12 User’s Manual Page 8 of 33

1.5 Characteristics

The module is characterized by the following parameters.

1.5.1 GPS Characteristics

Channels

Correlators

48, parallel tracking

～

400,000

Frequency

Tracking Sensitivity

On-module antenna

Horizontal Position Accuracy Stand alone

Time To First Fix – TTFF Obscuration recovery

(1)

(theoretical minimum values; values in real world may differ)

Hot start

(2)

Warm

(3)

Cold

(4)

L1 (= 1,575 MHz)

< 2.5 m CEP (SA off)

< 1 s

< 35 s

< 38 s

Table 1: A2235-H GPS characteristics

(1) The calibrated clock of the receiver has not stopped, thus it knows precise time (to the µs level).

(2) The receiver has estimates of time/date/position and valid almanac and ephemeris data.

(3) The receiver has estimates of time/date/position and recent almanac.

(4) The receiver has no estimate of time/date/position, and no recent almanac.

Note: Performance (sensitivity and TTFF) might slightly decrease below -30°C.

1.5.2 Mechanical Characteristics

A2235-H Mechanical dimensions

A2235-H Weight

Length

Width

Height

17.78±0.20 mm, 0.7±0.008”

16.51±0.20 mm, 0.65±0.008”

7.11 mm, 0.28”(Max)

4.0 g, 0.14 oz

Table 2: A2235-H dimensions and weight

1.6 Handling Precautions

The GPS receiver module A2235-H is sensitive to electrostatic discharge (ESD).

Please handle with appropriate care.

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2 Ordering Information

2.1 GPS Receiver A20235-H

The order number is built as follows:

• A2235-Hxxxx

A2235-H is the model name. The “xxxx” refers to the current part number on the module.

2.2 Packing

The A2235-H GPS modules come in a tape and reel package suitable for pick and place machines.

Figure 2: A2235-H tape specifications (1)

V0.1 – Aug-12 User’s Manual Page 10 of 33

Figure 3: A2235-H tape specifications (2)

V0.1 – Aug-12

Figure 4: A2235-H tape specifications (3)

User’s Manual Page 11 of 33

One complete reel holds 500 (TBC) A2235-H modules.

There are 2 kinds of packaging for shipment (TBC):

A: One box holds 1 reel

Reel diameter: 38 cm

Outer Box dimensions: 38.8 (W) x 38.8 (L) x 5.7 (H) cm

Gross weight: 5.06 Kg

Net weight: 4.13 Kg

B: One box holds 2 reels

Reel diameter: 38 cm

Outer box dimensions: 38 (W) x 38 (L) x 12.3 (H) cm

Gross weight: 10.03 Kg

Net weight: 8.26 Kg

V0.1 – Aug-12 User’s Manual Page 12 of 33

2.3 Additional Equipment

EVA2235-H Evaluation Kit (including one module A2235-H)

A detailed description of the EVA2235-H Evaluation Kit can be found in the appropriate manual.

Table 3: Additional equipment

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3 Quick Start

In order to allow an easy and quick start with the A2235-H module, this chapter provides a short overview on the important steps to be taken to receive NMEA messages with position information on a serial port (UART).

NOTE 1 : The A2235-H needs an external pull-up resistor to be configured for

UART operation. Please consider the pull-up resistor in your design or pull the

GPIO up right after reset by other means.

NOTE 2 : The ON_OFF input of the A2235-H needs to be connected to a push-pull output of a microprocessor. For a wake-up, including the initial one after power on, a LOW-HIGH transmission is mandatory.

NOTE 3 : It is recommended to connect the nRST pin of the A2235-H to an open collector / open drain output of a microprocessor!

3.1 Minimum Configuration

The following picture shows the minimum configuration for NMEA or binary outputs received and commands sent via an RS232 interface based on the GPS module

A2235-H.

V0.1 – Aug-12

Figure 5: Minimum configuration A2235-H

NOTE : It is recommended to supply Vcc continuously! Use SiRFaware

TM

or other low power modes to reduce power consumption of the module while no position information is required.

User’s Manual Page 14 of 33

For completeness the following picture shows the use of an RS232 level shifter.

Figure 6: RS232 level shifter for minimum configurations

Remarks:

• Place C1 to C5 (here: 0.1µF) close to MAX3232. For capacity values see datasheet of actual component used.

• Use 3.3V level shifter (MAX3232 or equivalent).

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3.2 Antenna

The A2235-H connected to a ceramic passive GPS patch antenna.

3.3 Serial Port Settings

The default configuration within the custom-specific GPS firmware is:

• Serial 0 (NMEA) 4800 baud, 8 data bits, no parity, 1 stop bit, no flow control

3.4 Improved TTFF

In order to improve the TTFF (Time To First Fix), it is recommended to keep Vcc supplied at all times. This will allow taking advantage of sophisticated low power mode features of the SiRFstarIV ROM chip set.

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4 Mechanical Outline

4.1 Details Component Side A2235-H

All dimensions in [mm] / [(inches)]

Figure 7: Mechanical outline component side A2235-H

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4.2 Details Solder Side A2235-H

Solder pad size (outer pads): 1.0 x 0.8

Solder pad size (inner pads): 1.27 x 1.27

All dimensions in [mm]

Figure 8: Mechanical outline solder side A2235-H

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5 Pin-out Information

5.1 Layout A2235-H

Figure 9: Pin-out information (top view) A2235-H

V0.1 – Aug-12 User’s Manual Page 19 of 33

5.2 Description A2235-H Signals

Pin Symbol Function Description

1 nRST Input Reset input, active low

2 GPIO3 None

3 VCC3V3 Power Supply 3.0 – 3.6 V DC

4 WAKEUP Output Status of digital section

5 Vout Voltage Permanent 1.8V voltage output for up to 20mA

6 GND

Output current max.

Power Supply Ground (power supply)

7 GPIO6

CTS

(SPI CLK)

8 GPIO7

RTS

(SPI CS)

Input

Input

Configuration pin for communication mode. 10K to

1.8V for UART mode; leave open for SPI & host port

I2C modes.

SPI clock pin when module works in SPI mode

Configuration pin for communication mode. 10K to

GND for host port I2C mode; leave open for SPI &

UART modes.

SPI chip select pin when module works in SPI mode

9 GND Power Supply Ground (power supply)

10 GPIO2 None

Port

I2C_CLK

Input Host port I2C clock pin when module works in host port I2C mode

12 GPIO4 Input

13 TM_GPIO5 Output

14 I2C CLK Input

15 I2C DIO

16 ON_OFF

17 ExtInt

(GPIO8)

External interrupt input pin – reserved for future use, leave open

Time Mark – 1PPS signal

I2C clock input for MEMS interface

Input / Output I2C I/O for MEMS interface

Input

Input

Connect to push-pull output is mandatory.

- Set to LOW by default

- Toggle to HIGH and back to LOW

> for first start-up after power on

> to request a fix in SiRFawareTM or PTF mode

> to go into or wake up out of hibernate mode

Interrupt input for MEMS interface (If ExtInt is not going to be used, it is recommended that this pin be tied directly to ground. Otherwise, a 100K pull-down resistor to ground should be connected to the ExtInt pin.)

/

(SPI DO)

/

(SPI DI) /

(Host Port

I2C_DIO)

Output

Input

Serial output 0.NMEA out if configured for UART;

SPI data out pin when module works in SPI mode.

Serial input 0.NMEA in if configured for UART;

SPI data in pin when module works in SPI mode;

Host port I2C data I/O pin when module works in hist port I2C mode.

Table 4: Pin description A2235-H

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6 Electrical Characteristics

6.1 Operating Conditions

Pin Description

3

Full power mode (Searching) Peak Current (1)

Min Typical Max

69mA

Full power mode (Searching) Average Current (2)

Full power mode (Tracking) Average Current (3)

TricklePower™ Mode

Push-to-Fix Mode

Micro Power Mode（

SiRFaware

TM

）

56mA

31mA

14mA

46.4uA

45uA

Hibernate Status 27uA

Table 5: A2235-H electrical characteristics

(1) Peak searching current is characterized by millisecond bursts above average searching current

(2) Average searching current is typically only the first two seconds of TTFF

(3) Tracking current typically includes tracking and the post searching portion of TTFF

6.2 Absolute Maximum Ratings

Symbol Parameter

Vin

Iov

Itdv

-0.3 V

Voltage to I/O pin

Input current on any pin

-0.3 +3.6

-10 10

V mA

Absolute sum of all input currents during overload condition 200 mA

Table 6: Absolute maximum ratings

Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress rating only. Functional operation of the device at these or any other conditions beyond those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.

V0.1 – Aug-12 User’s Manual Page 21 of 33

6.3 DC Electrical Characteristics

Symbol Parameter

TX0, WAKEUP Voh @ 4mA 2.6 Vcc V

Vol @ 4mA

RX0 Vih

Vil nRST For safe reset

0.45 V

V

0.2 V

ON_OFF Vih

Vil

Table 7: DC electrical characteristics

V0.1 – Aug-12 User’s Manual Page 22 of 33

7 Mounting

This chapter describes the suggested mounting process for the A2235-H GPS receiver modules. In a RoHS compliant product with a RoHS compliant process it is recommended to use chemical tin as the counter-part to the module’s pins. This will guarantee highest resistance against shocks.

7.1 Proposed Footprint for Soldering

The following proposal of a footprint for soldering is assuming a stencil thickness of

150µm. ³ marks the center of the through holes.

Figure 10: Proposal of Soldering footprint

Please note that copper and solder paste footprint are identical. The final footprint has to be evaluated and qualified by the manufacturer according to the specific processes.

7.2 PCB Design Guide

1. Drill a through hole with diameter greater than or equal to 3mm in the application

PCB which underneath the RF feed-point to allivate the interference from RF signal to other part of circuitries. Besides, ground vias (says, 8) should be placed surrounding the through hole for further shielding purpose.

 

V0.1 – Aug-12 User’s Manual Page 23 of 33

Figure 11: Proposal (1) of the PCB design

2. If proposal 1 is not allowed. Placd a round Copper keep out region (diameter ≥

3mm) on the application PCB underneath the RF feed-point to allivate the interference from RF signal to other part of circuitries. Besides, ground vias (says, 8) should be placed surrounding the through hole for further shielding purpose.

.

V0.1 – Aug-12

Figure 12: Proposal (2) of the PCB design

User’s Manual Page 24 of 33

7.3 Recommended Profile for Reflow Soldering

Typical values for reflow soldering of the module in convection or IR/convection ovens are as follows (according to IPC/JEDEC J-STD-020D):

Parameter Value

Peak temperature (RoHS compliant process) 245°C

Average ramp up rate to peak (217°C to Peak)

Preheat temperature

3°C / second max. min=150°C; max=200°C

Ramp up time from min. to max. preheat temperature 60 … 120 seconds

Temperature maintained above 217°C 60 … 150 seconds

Time within 5°C of actual peak temperature

Ramp down rate

30 seconds

6°C / second max.

Time 25°C to peak temperature 8 minutes max.

Table 8: Reflow soldering profile A2235-H

As results of soldering may vary among different soldering systems and types of solder and depend on additional factors like density and types of components on board, the values above should be considered as a starting point for further optimization.

V0.1 – Aug-12 User’s Manual Page 25 of 33

8 Quality and Reliability

8.1 Environmental Conditions

Operating temperature

-40°C … +85

°C

Operating humidity

Max. 85% r. H., non-condensing, at 85

°C

MSL JEDEC (Moisture Sensitivity Level) 3

Storage 6 months in original package

Table 9: Environmental conditions

8.2 Product Qualification

Prior to product qualification the GPS receiver is preconditioned according to

EIA/JEDEC standard JESD22-A113-B / Level 3.

Basic qualification tests:

• MSL Classification according to J-STD-020C (MSL3 @ 245°C)

(Refer to report : SZRL2011110048)

• MSL Rework Compatibility according to J-STD-020C

(Refer to report : SZRL2011110048)

• Temperature Cycling –40°C … +85°C

• Temperature Humidity Bias 70°C / 85% RH

• Low / High Temperature Operating –40°C / +85°C

• High Temperature Operating Life +85°C

• Vibration Variable Frequency

Please contact Maestro for detailed information.

8.3 Production Test

Each module is electrically tested prior to packing and shipping to ensure state of the art GPS receiver performance and accuracy.

V0.1 – Aug-12 User’s Manual Page 26 of 33

9 Applications and Hints

9.1 Initial Module Start

After initially applying power to the module, it is necessary to start the internal firmware by toggling the ON_OFF pin. Toggling is done by pulling the signal to HIGH for about 200ms. This first toggling can be done after a LOW – HIGH transmission was detected at the WAKEUP pin or by simply waiting for 1s after power-up. In case of configuration for UART mode, messages should be transmitted afterwards. If no messages should appear, a new toggling should be applied.

9.2 Proper Shutdown and Power-On-Reset (POR)

The A2235-H modules require an orderly shutdown process to properly stop internal operation and complete any writes of critical data to BBRAM or EEPROM data area.

Abrupt removal or drop of main power while the system is running has risks ranging from minor impact on TTFF to fatal, permanent corruption of EEPROM code area on the module (Please refer to “Power ONOFF Sequences and Power -On-Reset (POR) on A2100-AB Application Notes”).

A controlled and orderly shutdown while the A2235-H is running in full power mode can be initiated by

• A 200ms pulse on the ON_OFF pin,

• According messages either in NMEA or OSP mode.

The shutdown is completed after maximum 1s. Therefore the module should be supplied with voltage for that time after the shutdown sequence was initiated.

9.3 SiRFaware

TM

Support

SiRFaware

TM

is a low-power operating mode that seeks to maintain low uncertainty in position, time, and frequency, and to maintain valid current Ephemeris using either data collected from satellites in view or Extended Ephemeris methods.

The SiRFaware

TM

mode is entered using the One Socket Protocol, an extension of the SiRF Binary Protocol. Please refer to the appropriate manual. In order to request a fix and to exit SiRFaware

TM

it is necessary to toggle the ON_OFF pin. Toggling is done by pulling the signal to HIGH for about 200ms.

9.4 Push-to-Fix Mode

Push-to-Fix mode is designed for the application that requires infrequent position reporting. The receiver generally stays in a low-power mode, up to 2 hours, but wakes up periodically to refresh position, time, ephemeris data and RTC calibration.

V0.1 – Aug-12 User’s Manual Page 27 of 33

The push-to-fix mode is initialized and entered using the SiRF Binary Protocol.

Please refer to the appropriate manual, paying particular attention to the paragraph titled “Set TricklePower Parameters”. In order to request a fix outside the specified duty cycles, it is necessary to toggle the ON_OFF pin. Toggling is done by pulling the signal to HIGH for about 200ms.

9.5 Hibernate Mode

In order to enter Hibernate Mode it is necessary to send a shutdown command or to toggle to ON_OFF pin by pulling the signal to HIGH for about 200ms. Starting with firmware version 4.0.1 the according command is supported in NMEA and SiRF

Binary mode. After a short delay the module will switch into hibernate mode. The

RTC will keep on running and SRAM is backed with the typical current of 20 μA drawn from Vcc. To wake the module up again, toggling the ON_OFF pin is necessary (200ms pulse width).

9.6 Extended Ephemeris

The receiver is capable of supporting two versions of using Extended Ephemeris (EE) data. The first one is the version, where the EE data are calculated on a server, are transmitted to device incorporating the receiver, and are then loaded into the receiver.

These data can be valid for up to seven days.

The second version is the internal extrapolation of available “natural” Ephemeris data.

This is done automatically and no external support is required. The internally calculated EE data are valid for up to 3 days.

The receiver firmware will define which set of EE data to use or will neglect those in case “natural” data are available (need add an external EEPROM part) . Both versions of EE data will help to further lower power consumption in SiRFaware

TM

mode.

9.7 TM_GPIO5 pin (1 pulse per second pin)

The 1PPS pin is an output pin.

In addition to precise positioning, GPS also allows for accurate timing due to the synchronized atomic clocks in the GPS satellites. While the current date and time is transmitted in NMEA sentences (UTC), an exact and accurate timing signal is provided via the 1PPS pin of the A2035-H GPS receiver.

Under good signal conditions the 1PPS signal comes between 620ns and 710ns after the full GPS system second which is accurately (around 10ns) synchronized to

UTC. Therefore the 1 second clock can be derived and maintained within around

90ns under good signal conditions.

Note:

The 1PPS clock accuracy directly depends on the position accuracy!

V0.1 – Aug-12 User’s Manual Page 28 of 33

The GPS signals travel at the speed of light, therefore a position inaccuracy directly translates into 1PPS inaccuracies.

10m position deviation ≈ 33ns 1PPS deviation (typically)

100m position deviation ≈ 333ns 1PPS deviation (typically)

The NMEA messages containing absolute timing information (UTC time) are provided around 300ms after the 1PPS signal typically. This may change with the GPS receiver setup.

The 1PPS signal is provided on a “as is” basis with no accuracy specification. It’s

NOT recommended to use 1PPS signal for accurate timing application.

The given values are based on a 10 satellite, static GPS simulator scenario.

V0.1 – Aug-12 User’s Manual Page 29 of 33

10 Evaluation Kit EVA2235-H

For demonstration and easy evaluation of GPS performance Maestro offers an evaluation kit (including one GPS A2235-H module). It contains a USB interface with according drivers to connect easily to a PC. The USB interface is an extension of the serial port 0, therefore sending NMEA sentences and accepting commands. At the same time it provides power to the module. Accompanied by an antenna it offers a ready-to-go set.

For the development of new software and applications the Evaluation Kit also provides NMEA messages on CMOS level via a terminal plug.

Figure 13: Evaluation kit EVA2235-H

For further information please contact Maestro.

V0.1 – Aug-12 User’s Manual Page 30 of 33

11 Related Information

11.1 Contact

This manual was created with due diligence. We hope that it will be helpful to the user to get the most out of the GPS module.

Any inputs regarding possible errors or mistakable verbalizations, and comments or proposals for further improvements to this document, made to Maestro, HongKong, are highly appreciated.

Maestro Wireless Solutions Limited

Add:Unit 3603-09,36/F.,118 Connaught Road West,HK

Main Line: (852) 28690688

Fax: (852)25254701 [email protected] www.maestro-wireless.com

11.2 Related Documents

• GPS Evaluation Kit EVA2235-H (Maestro)

• Power ONOFF Sequences and Power-On-Reset (POR) on A2100-AB (Maestro)

• SiRF_OSP_Reference_Manual (SiRF)

• SiRF_NMEA_Reference_Manual (SiRF)

11.3 Related Tools

• GPS Cockpit (Maestro)

(SiRF)

V0.1 – Aug-12 User’s Manual Page 31 of 33

12 List of Figures

Figure 1: A2235-H label ........................................................................................... 8

Figure 2: A2235-H tape specifications (1) .............................................................. 10

Figure 3: A2235-H tape specifications (2) .............................................................. 11

Figure 4: A2235-H tape specifications (3) .............................................................. 11

Figure 5: Minimum configuration A2235-H............................................................. 14

Figure 6: RS232 level shifter for minimum configurations ...................................... 15

Figure 7: Mechanical outline component side A2235-H ......................................... 17

Figure 8: Mechanical outline solder side A2235-H................................................. 18

Figure 9: Pin-out information (top view) A2235-H .................................................. 19

Figure 10: Proposal of Soldering footprint.............................................................. 23

Figure 11: Proposal (1) of the PCB design............................................................ 24

Figure 12: Proposal (2) of the PCB design............................................................. 24

Figure 13: Evaluation kit EVA2235-H..................................................................... 30

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13 List of Tables

Table 1: A2235-H GPS characteristics..................................................................... 9

Table 2: A2235-H dimensions and weight................................................................ 9

Table 3: Additional equipment................................................................................ 13

Table 4: Pin description A2235-H .......................................................................... 20

Table 5: A2235-H electrical characteristics ............................................................ 21

Table 6: Absolute maximum ratings ....................................................................... 21

Table 7: DC electrical characteristics ..................................................................... 22

Table 8: Reflow soldering profile A2235-H............................................................. 25

Table 9: Environmental conditions ......................................................................... 26

V0.1 – Aug-12 User’s Manual Page 33 of 33