Texas Instruments | bq4050 CEDV Gas Gauge and Protection Solution for 1-Series to 4-Series Cell Li-Ion Battery Packs (Rev. B) | Datasheet | Texas Instruments bq4050 CEDV Gas Gauge and Protection Solution for 1-Series to 4-Series Cell Li-Ion Battery Packs (Rev. B) Datasheet

Texas Instruments bq4050 CEDV Gas Gauge and Protection Solution for 1-Series to 4-Series Cell Li-Ion Battery Packs (Rev. B) Datasheet
Product
Folder
Order
Now
Support &
Community
Tools &
Software
Technical
Documents
bq4050
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
bq4050 CEDV Gas Gauge and Protection Solution for
1-Series to 4-Series Cell Li-Ion Battery Packs
1 Features
3 Description
•
The Texas Instruments bq4050 device, incorporating
Compensated End-of-Discharge Voltage (CEDV)
technology, is a highly integrated, accurate, 1-series
to 4-series cell gas gauge and protection solution,
enabling autonomous charger control and cell
balancing.
1
•
•
•
•
•
•
•
•
•
•
High-Side Protection N-CH FET Drive Enables
Serial Bus Communication During Fault
Conditions
Cell Balancing with Internal Bypass Optimizes
Battery Health
Diagnostic Lifetime Data Monitor and Black Box
Recorder for Failure Analysis
Full Array of Programmable Protection Features:
Voltage, Current, Temperature
JEITA Charge Algorithms Support Smart Charging
Analog Front End with Two Independent ADCs
– Simultaneous Current and Voltage Sampling
– High-Accuracy Coulomb Counter with Input
Offset Error < 1 μV (Typical)
Supports Battery Trip Point (BTP) Function for
Windows® Integration
LED Display for State of Charge and Battery
Status Indication
100-KHz SMBus v1.1 Communications Interface
for Programming and Data Access with Alternate
400-KHz Mode
SHA-1 Authentication Responder for Increased
Battery Pack Security
Compact 32-Pin VQFN Package (RSM)
The bq4050 device provides a fully integrated packbased solution with a flash programmable custom
reduced
instruction-set
CPU
(RISC),
safety
protection, and authentication for Li-Ion and LiPolymer battery packs.
The bq4050 gas gauge communicates via an SMBuscompatible interface and combines an ultra-low
power, high-speed TI bqBMP processor, highaccuracy analog measurement capabilities, integrated
flash memory, an array of peripheral and
communication ports, an N-CH FET drive, and a
SHA-1 Authentication transform responder into a
complete, high-performance battery management
solution.
Device Information(1)
PART NUMBER
bq4050
PACKAGE
BODY SIZE (NOM)
VQFN (32)
4.00 mm × 4.00 mm
(1) For all available packages, see the orderable addendum at
the end of this data sheet.
Simplified Schematic
2 Applications
VC4
PACK
VCC
DSG
CHG
PCHG
BAT
PTC
PACK +
Notebooks
Medical and Test Equipment
Portable Instrumentation
Cordless Vacuum Cleaners and Vacuum Robots
FUSE
•
•
•
•
LEDCNTLA
LEDCNTLB
LEDCNTLC
VC3
GND
nd
VDD
VC3
2 level
protector
OUT
VC2
Cell 3
VC2
DISP
Cell 2
VC1
SMBD
SMBC
PBI
VSS SRP SRN TS1 TS2 TS3 TS4 BTP PRES
VC1
Cell 1
SMBD
SMBC
PRES
BTP
PACK–
Copyright © 2017, Texas Instruments Incorporated
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.
bq4050
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
www.ti.com
Table of Contents
1
2
3
4
5
6
Features ..................................................................
Applications ...........................................................
Description .............................................................
Revision History.....................................................
Pin Configuration and Functions .........................
Specifications.........................................................
6.25 Electrical Characteristics: High-Frequency
Oscillator .................................................................. 14
6.26 Electrical Characteristics: Low-Frequency
Oscillator .................................................................. 15
6.27 Electrical Characteristics: Voltage Reference 1.... 15
6.28 Electrical Characteristics: Voltage Reference 2.... 15
6.29 Electrical Characteristics: Instruction Flash .......... 15
6.30 Electrical Characteristics: Data Flash ................... 15
6.31 Electrical Characteristics: OCD, SCC, SCD1, SCD2
Current Protection Thresholds ................................. 16
6.32 Timing Requirements: OCD, SCC, SCD1, SCD2
Current Protection Timing ........................................ 17
6.33 Timing Requirements: SMBus .............................. 17
6.34 Timing Requirements: SMBus XL......................... 18
6.35 Typical Characteristics .......................................... 19
1
1
1
2
3
7
6.1
6.2
6.3
6.4
6.5
6.6
6.7
6.8
Absolute Maximum Ratings ...................................... 7
ESD Ratings.............................................................. 7
Recommended Operating Conditions....................... 8
Thermal Information .................................................. 8
Electrical Characteristics: Supply Current................. 8
Electrical Characteristics: Power Supply Control...... 9
Electrical Characteristics: AFE Power-On Reset ...... 9
Electrical Characteristics: AFE Watchdog Reset and
Wake Timer................................................................ 9
6.9 Electrical Characteristics: Current Wake
Comparator ................................................................ 9
6.10 Electrical Characteristics: VC1, VC2, VC3, VC4,
BAT, PACK .............................................................. 10
6.11 Electrical Characteristics: SMBD, SMBC.............. 10
6.12 Electrical Characteristics: PRES, BTP_INT, DISP
................................................................................. 10
6.13 Electrical Characteristics: LEDCNTLA, LEDCNTLB,
LEDCNTLC ............................................................. 11
6.14 Electrical Characteristics: Coulomb Counter ........ 11
6.15 Electrical Characteristics: CC Digital Filter ........... 11
6.16 Electrical Characteristics: ADC ............................. 12
6.17 Electrical Characteristics: ADC Digital Filter ......... 12
6.18 Electrical Characteristics: CHG, DSG FET Drive . 12
6.19 Electrical Characteristics: PCHG FET Drive ......... 13
6.20 Electrical Characteristics: FUSE Drive.................. 13
6.21 Electrical Characteristics: Internal Temperature
Sensor...................................................................... 13
6.22 Electrical Characteristics: TS1, TS2, TS3, TS4 .... 14
6.23 Electrical Characteristics: PTC, PTCEN ............... 14
6.24 Electrical Characteristics: Internal 1.8-V LDO....... 14
7
Detailed Description ............................................ 22
7.1
7.2
7.3
7.4
8
Overview .................................................................
Functional Block Diagram ......................................
Feature Description.................................................
Device Functional Modes........................................
22
22
23
26
Applications and Implementation ...................... 27
8.1 Application Information .......................................... 27
8.2 Typical Applications ................................................ 28
9 Power Supply Recommendations...................... 42
10 Layout................................................................... 42
10.1 Layout Guidelines ................................................. 42
10.2 Layout Example .................................................... 44
11 Device and Documentation Support ................. 46
11.1
11.2
11.3
11.4
11.5
Documentation Support ........................................
Community Resources..........................................
Trademarks ...........................................................
Electrostatic Discharge Caution ............................
Glossary ................................................................
46
46
46
46
46
12 Mechanical, Packaging, and Orderable
Information ........................................................... 46
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision A (April 2016) to Revision B
•
2
Page
Changed Applications............................................................................................................................................................. 1
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
bq4050
www.ti.com
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
5 Pin Configuration and Functions
BAT
CHG
PCHG
NC
DSG
PACK
VCC
FUSE
32
31
30
29
28
27
26
25
RSM Package
32-Pin VQFN with Exposed Thermal Pad
Top View
PBI
1
24
PTCEN
VC4
2
23
PTC
VC3
3
22
LEDCNTLC
VC2
4
21
LEDCNTLB
Thermal
Pad
14
15
16
NC
BTP_INT
PRES_or_SHUTDN
13
DISP
TS4
SMBD
17
12
18
8
11
7
TS3
NC
SRP
TS2
SMBC
10
LEDCNTLA
19
9
20
6
TS1
5
VSS
VC1
SRN
Pin Functions
PIN
NAME
NUMBER
TYPE
DESCRIPTION
PBI
1
P (1)
VC4
2
IA
Sense voltage input pin for the most positive cell, and balance current input for the most
positive cell
VC3
3
IA
Sense voltage input pin for the second most positive cell, balance current input for the
second most positive cell, and return balance current for the most positive cell
VC2
4
IA
Sense voltage input pin for the third most positive cell, balance current input for the third
most positive cell, and return balance current for the second most positive cell
VC1
5
IA
Sense voltage input pin for the least positive cell, balance current input for the least
positive cell, and return balance current for the third most positive cell
SRN
6
I
NC
7
—
SRP
8
I
Analog input pin connected to the internal coulomb counter peripheral for integrating a
small voltage between SRP and SRN where SRP is the top of the sense resistor.
Power supply backup input pin
Analog input pin connected to the internal coulomb counter peripheral for integrating a
small voltage between SRP and SRN where SRP is the top of the sense resistor.
Not internally connected. Connect to VSS.
VSS
9
P
Device ground
TS1
10
IA
Temperature sensor 1 thermistor input pin
TS2
11
IA
Temperature sensor 2 thermistor input pin
TS3
12
IA
Temperature sensor 3 thermistor input pin
TS4
13
IA
Temperature sensor 4 thermistor input pin
NC
14
—
Not internally connected. Connect to VSS.
BTP_INT
15
O
Battery Trip Point (BTP) interrupt output
PRES or
SHUTDN
16
I
Host system present input for removable battery pack or emergency system shutdown
input for embedded packs
(1)
P = Power Connection, O = Digital Output, AI = Analog Input, I = Digital Input, I/OD = Digital Input/Output
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
3
bq4050
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
www.ti.com
Pin Functions (continued)
PIN
NAME
NUMBER
TYPE
DESCRIPTION
DISP
17
—
SMBD
18
I/OD
SMBus data pin
SMBC
19
I/OD
SMBus clock pin
LEDCNTLA
20
—
LED display segment that drives the external LEDs depending on the firmware
configuration
LEDCNTLB
21
—
LED display segment that drives the external LEDs depending on the firmware
configuration
LEDCNTLC
22
—
LED display segment that drives the external LEDs depending on the firmware
configuration
PTC
23
IA
Safety PTC thermistor input pin. To disable, connect PTC and PTCEN to VSS.
PTCEN
24
IA
Safety PTC thermistor enable input pin. Connect to BAT. To disable, connect PTC and
PTCEN to VSS.
FUSE
25
O
Fuse drive output pin
VCC
26
P
Secondary power supply input
PACK
27
IA
Pack sense input pin
DSG
28
O
NMOS Discharge FET drive output pin
NC
29
—
Not internally connected. Connect to VSS.
PCHG
30
O
PMOS Precharge FET drive output pin
CHG
31
O
NMOS Charge FET drive output pin
BAT
32
P
Primary power supply input pin
4
Display control for LEDs
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
bq4050
www.ti.com
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
VC4
BAT
VCC
CDEN4
PACK
VC3
+
–
3.1 V
BATDET
ENVCC
CDEN3
PACK
Detector
VC2
PACKDET
PBI
Reference
System
Shutdown
Latch
1.8 V
Domain
VC1
BAT
Control
Power Supply Control
ADC
CDEN2
SHOUT
ENBAT
ADC Mux
SHUTDOWN
CDEN1
Cell Balancing
VCC
CHGEN
BAT
2 kΩ
CHG
Pump
CHG
8 kΩ
2 kΩ
PCHG
CHGOFF
PCHGEN
Pre-Charge Drive
PACK
BAT
DSGEN
BAT
DSG
Pump
ZVCD
2 kΩ
DSG
CHGEN
BAT
DSGOFF
CHG
Pump
VCC
ZVCHGEN
CHG, DSG Drive
Zero-Volt Charge
Figure 1. Pin Equivalent Diagram 1
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
5
bq4050
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
www.ti.com
1.8 V
ADTHx
BAT
FUSEWKPUP
18 kΩ
2 kΩ
ADC Mux
TS1,2,3,4
ADC
FUSEEN
150 nA
2 kΩ
FUSE
1.8 V
1.8 V
100 kΩ
FUSEDIG
RCWKPUP
RCPUP
FUSE Drive
1 kΩ
RCIN
RCOUT
100 kΩ
SMBCIN
SMBC
Thermistor Inputs
SMBCOUT
SMBCEN
1 MΩ
PBI
100 kΩ
SMBDIN
RHOEN
SMBD
SMBDOUT
10 kΩ
PRES
SMBDEN
1 MΩ
SMBus Interface
RHOUT
100 kΩ
RHIN
High-Voltage GPIO
PTCEN
BAT
30 kΩ
PTC
Comparator
PTC
RLOEN
PTC
Counter
PTC
Latch
PTCDIG
290 nA
LED1, 2, 3
22.5 mA
RLOUT
100 kΩ
RLIN
LED Drive
PTC Detection
Figure 2. Pin Equivalent Diagram 2
6
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
bq4050
www.ti.com
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
10 Ω
VC4
CHANx
Φ2
3.8 kΩ
1.9 MΩ
SRP
ADC Mux
Φ1
ADC
Φ2
3.8 kΩ
0.1 MΩ
SRN
Comparator
Array
Φ1
Φ2
10 Ω
100 Ω
PACK
Φ1
Coulomb
Counter
Φ2
CHANx
100 Ω
Φ1
1.9 MΩ
ADC Mux
ADC
0.1 MΩ
OCD, SCC, SCD Comparators and Coulomb Counter
VC4 and PACK Dividers
Figure 3. Pin Equivalent Diagram 3
6 Specifications
6.1 Absolute Maximum Ratings
Over-operating free-air temperature range (unless otherwise noted) (1)
Supply voltage range, VCC
Input voltage range, VIN
Output voltage range, VO
MIN
MAX
UNIT
BAT, VCC, PBI
–0.3
30
V
PACK, SMBC, SMBD, PRES or SHUTDN, BTP_INT, DISP
–0.3
30
V
TS1, TS2, TS3, TS4
–0.3
VREG + 0.3
V
PTC, PTCEN, LEDCNTLA, LEDCNTLB, LEDCNTLC
–0.3
VBAT + 0.3
V
SRP, SRN
–0.3
0.3
V
VC4
VC3 – 0.3
VC3 + 8.5 V, or
VSS + 30
V
VC3
VC2 – 0.3
VC2 + 8.5 V, or
VSS + 30
V
VC2
VC1 – 0.3
VC1 + 8.5 V, or
VSS + 30
V
VC1
VSS – 0.3
VSS + 8.5 V, or
VSS + 30 V
V
CHG, DSG
–0.3
32
PCHG, FUSE
–0.3
30
V
50
mA
150
°C
300
°C
Maximum VSS current, ISS
TSTG
Storage temperature
–65
Lead temperature (soldering, 10 s), TSOLDER
(1)
Stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. These are stress ratings
only, and functional operation of the device at these or any other conditions beyond those indicated under recommended operating
conditions is not implied. Exposure to absolute–maximum–rated conditions for extended periods may affect device reliability.
6.2 ESD Ratings
VALUE
Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001
V(ESD)
(1)
(2)
Electrostatic discharge
Charged-device model (CDM), per JEDEC specification
JESD22-C101 (2)
(1)
UNIT
±2000
±500
V
JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
7
bq4050
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
www.ti.com
6.3 Recommended Operating Conditions
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
MIN
VCC
Supply voltage
BAT, VCC, PBI
VSHUTDOWN–
Shutdown voltage
VPACK < VSHUTDOWN–
VSHUTDOWN+
Start-up voltage
VPACK > VSHUTDOWN– + VHYS
VHYS
Shutdown voltage
hysteresis
VSHUTDOWN+ – VSHUTDOWN–
NOM
2.2
Input voltage range
UNIT
26
V
1.8
2.0
2.2
V
2.05
2.25
2.45
V
250
PACK, SMBC, SMBD, PRES, BTP_IN, DISP
VIN
MAX
mV
26
TS1, TS2, TS3, TS4
VREG
PTC, PTCEN, LEDCNTLA, LEDCNTLB, LEDCNTLC
VBAT
SRP, SRN
–0.2
0.2
VC4
VVC3
VVC3 + 5
VC3
VVC2
VVC2 + 5
VC2
VVC1
VVC1 + 5
VC1
VVSS
VVSS + 5
VO
Output voltage
range
CPBI
External PBI
capacitor
2.2
TOPR
Operating
temperature
–40
CHG, DSG, PCHG, FUSE
26
V
V
µF
85
°C
6.4 Thermal Information
bq4050
THERMAL METRIC
(1)
RSM (QFN)
UNIT
32 PINS
RθJA, High K
Junction-to-ambient thermal resistance
47.4
°C/W
RθJC(top)
Junction-to-case(top) thermal resistance
40.3
°C/W
RθJB
Junction-to-board thermal resistance
14.7
°C/W
ψJT
Junction-to-top characterization parameter
0.8
°C/W
ψJB
Junction-to-board characterization parameter
14.4
°C/W
RθJC(bottom)
Junction-to-case(bottom) thermal resistance
3.8
°C/W
(1)
For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application
report, SPRA953.
6.5 Electrical Characteristics: Supply Current
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 20 V (unless otherwise noted)
PARAMETER
INORMAL
NORMAL mode
ISLEEP
SLEEP mode
ISHUTDOWN
SHUTDOWN mode
8
TEST CONDITIONS
CHG on. DSG on, no Flash write
MIN
TYP
336
CHG off, DSG on, no SBS communication
75
CHG off, DSG off, no SBS communication
52
1.6
Submit Documentation Feedback
MAX
UNIT
µA
µA
µA
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
bq4050
www.ti.com
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
6.6 Electrical Characteristics: Power Supply Control
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
PARAMETER
TEST CONDITIONS
VSWITCHOVER–
BAT to VCC
switchover
voltage
VBAT < VSWITCHOVER–
VSWITCHOVER+
VCC to BAT
switchover
voltage
VBAT > VSWITCHOVER– + VHYS
VHYS
Switchover
VSWITCHOVER+ – VSWITCHOVER–
voltage hysteresis
ILKG
RPD
Input Leakage
current
Internal pulldown
resistance
MIN
TYP
MAX
1.95
2.1
2.2
V
2.9
3.1
3.25
V
1000
mV
BAT pin, BAT = 0 V, VCC = 25 V, PACK = 25 V
1
PACK pin, BAT = 25 V, VCC = 0 V, PACK = 0 V
1
BAT and PACK terminals, BAT = 0 V, VCC = 0 V, PACK
= 0 V, PBI = 25 V
1
PACK
30
40
UNIT
50
µA
kΩ
6.7 Electrical Characteristics: AFE Power-On Reset
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
PARAMETER
TEST CONDITIONS
VREGIT–
Negative-going
voltage input
VREG
VHYS
Power-on reset
hysteresis
VREGIT+ – VREGIT–
tRST
Power-on reset
time
MIN
TYP
MAX
UNIT
1.51
1.55
1.59
V
70
100
130
mV
200
300
400
µs
6.8 Electrical Characteristics: AFE Watchdog Reset and Wake Timer
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
372
500
628
tWDT = 1000
744
1000
1256
tWDT = 2000
1488
2000
2512
tWDT = 4000
2976
4000
5024
tWAKE = 250
186
250
314
tWAKE = 500
372
500
628
tWAKE = 1000
744
1000
1256
tWAKE = 512
1488
2000
2512
409
512
614
tWDT = 500
tWDT
AFE watchdog
timeout
tWAKE
AFE wake timer
tFETOFF
FET off delay after
reset
tFETOFF = 512
UNIT
ms
ms
ms
6.9 Electrical Characteristics: Current Wake Comparator
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
PARAMETER
VWAKE
Wake voltage
threshold
TEST CONDITIONS
MIN
TYP
MAX
VWAKE = ±0.625 mV
±0.3
±0.625
±0.9
VWAKE = ±1.25 mV
±0.6
±1.25
±1.8
VWAKE = ±2.5 mV
±1.2
±2.5
±3.6
VWAKE = ±5 mV
±2.4
±5.0
±7.2
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
UNIT
mV
9
bq4050
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
www.ti.com
Electrical Characteristics: Current Wake Comparator (continued)
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
PARAMETER
VWAKE(DRIFT)
Temperature drift
of VWAKE accuracy
tWAKE
Time from
application of
current to wake
interrupt
tWAKE(SU)
Wake comparator
startup time
TEST CONDITIONS
MIN
TYP
MAX
0.5%
500
UNIT
°C
700
µs
1000
µs
6.10 Electrical Characteristics: VC1, VC2, VC3, VC4, BAT, PACK
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
0.1980
0.2000
0.2020
BAT–VSS, PACK–VSS
0.049
0.050
0.051
VREF2
0.490
0.500
0.510
VC1–VSS, VC2–VC1, VC3–VC2, VC4–VC3
K
Scaling factor
VC1–VSS, VC2–VC1, VC3–VC2, VC4–VC3
–0.2
5
BAT–VSS, PACK–VSS
–0.2
20
VIN
Input voltage range
ILKG
Input leakage current
VC1, VC2, VC3, VC4, cell balancing off, cell detach
detection off, ADC multiplexer off
RCB
Internal cell balance
resistance
RDS(ON) for internal FET switch at 2 V < VDS < 4 V
ICD
Internal cell detach
check current
VCx > VSS + 0.8 V
30
50
UNIT
—
V
1
µA
200
Ω
70
µA
6.11 Electrical Characteristics: SMBD, SMBC
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
VIH
Input voltage high
SMBC, SMBD, VREG = 1.8 V
1.3
VIL
Input voltage low
SMBC, SMBD, VREG = 1.8 V
0.8
VOL
Output low voltage
SMBC, SMBD, VREG = 1.8 V, IOL = 1.5 mA
0.4
CIN
Input capacitance
ILKG
Input leakage current
RPD
Pulldown resistance
V
5
0.7
UNIT
1.0
V
V
pF
1
µA
1.3
MΩ
6.12 Electrical Characteristics: PRES, BTP_INT, DISP
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
PARAMETER
VIH
High-level input
VIL
Low-level input
VOH
Output voltage high
VOL
Output voltage low
CIN
Input capacitance
ILKG
Input leakage current
10
TEST CONDITIONS
MIN
TYP
MAX
1.3
V
0.55
VBAT > 5.5 V, IOH = –0 µA
3.5
VBAT > 5.5 V, IOH = –10 µA
1.8
V
V
IOL = 1.5 mA
0.4
5
V
pF
1
Submit Documentation Feedback
UNIT
µA
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
bq4050
www.ti.com
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
Electrical Characteristics: PRES, BTP_INT, DISP (continued)
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
PARAMETER
TEST CONDITIONS
Output reverse
resistance
RO
MIN
Between PRES or BTP_INT or DISP and PBI
TYP
MAX
UNIT
8
kΩ
6.13 Electrical Characteristics: LEDCNTLA, LEDCNTLB, LEDCNTLC
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
PARAMETER
TEST CONDITIONS
VIH
High-level input
VIL
Low-level input
MIN
TYP
MAX
UNIT
1.45
V
0.55
VOH
Output voltage high
VBAT > 3.0 V, IOH = –22.5 mA
VOL
Output voltage low
IOL = 1.5 mA
ISC
High level output
current protection
IOL
Low level output
current
VBAT > 3.0 V, VOH = 0.4 V
ILEDCNTLx
Current matching
between LEDCNTLx
VBAT = VLEDCNTLx + 2.5 V
CIN
Input capacitance
ILKG
Input leakage current
fLEDCNTLx
Frequency of LED
pattern
V
VBAT –
1.6
V
0.4
V
–30
–45
–6 0
mA
15.75
22.5
29.25
mA
±1%
20
pF
1
µA
124
Hz
6.14 Electrical Characteristics: Coulomb Counter
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
PARAMETER
TEST CONDITIONS
Input voltage range
Full scale range
Integral nonlinearity (1)
16-bit, best fit over input voltage range
Offset error
Offset error drift
Gain error
15-bit + sign, over input voltage range
Gain error drift
15-bit + sign, over input voltage range
TYP
MAX
0.1
–VREF1/10
VREF1/10
UNIT
V
V
±5.2
±22.3
16-bit, Post-calibration
±5
±10
µV
15-bit + sign, Post-calibration
0.2
0.3
µV/°C
±0.2%
±0.8%
Effective input resistance
(1)
MIN
–0.1
150
LSB
FSR
PPM/°C
2.5
N
MΩ
15
1 LSB = VREF1/(10 × 2 ) = 1.215/(10 × 2 ) = 3.71 µV
6.15 Electrical Characteristics: CC Digital Filter
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
PARAMETER
TEST CONDITIONS
Conversion time
Single conversion
Effective resolution
Single conversion
MIN
TYP
MAX
UNIT
250
15
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
ms
Bits
11
bq4050
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
www.ti.com
6.16 Electrical Characteristics: ADC
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
PARAMETER
Input voltage range
Full scale range
Integral nonlinearity (1)
TEST CONDITIONS
MIN
TYP
MAX
Internal reference (VREF1)
–0.2
1
External reference (VREG)
–0.2
0.8 × VREG
VFS = VREF1 or VREG
–VFS
VFS
16-bit, best fit, –0.1 V to 0.8 × VREF1
±6.6
16-bit, best fit, –0.2 V to –0.1 V
±13.1
Offset error (2)
16-bit, Post-calibration, VFS = VREF1
±67
±157
Offset error drift
16-bit, Post-calibration, VFS = VREF1
0.6
3
Gain error
16-bit, –0.1 V to 0.8 × VFS
±0.2%
±0.8%
Gain error drift
16-bit, –0.1 V to 0.8 × VFS
150
Effective input resistance
(1)
(2)
N
8
UNIT
V
V
LSB
µV
µV/°C
FSR
PPM/°C
MΩ
15
1 LSB = VREF1/(2 ) = 1.225/(2 ) = 37.4 µV (when tCONV = 31.25 ms)
For VC1–VSS, VC2–VC1, VC3–VC2, VC4–VC3, VC4–VSS, PACK–VSS, and VREF1/2, the offset error is multiplied by (1/ADC
multiplexer scaling factor (K)).
6.17 Electrical Characteristics: ADC Digital Filter
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
PARAMETER
Conversion time
Resolution
Effective resolution
TEST CONDITIONS
MIN
TYP
Single conversion
31.25
Single conversion
15.63
Single conversion
7.81
Single conversion
1.95
No missing codes
16
With sign, tCONV = 31.25 ms
14
15
With sign, tCONV = 15.63 ms
13
14
With sign, tCONV = 7.81 ms
11
12
With sign, tCONV = 1.95 ms
9
10
MAX
UNIT
ms
Bits
Bits
6.18 Electrical Characteristics: CHG, DSG FET Drive
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
PARAMETER
Output voltage
ratio
V(FETON)
V(FETOFF)
tR
12
MIN
TYP
MAX
RatioDSG = (VDSG – VBAT)/VBAT, 2.2 V < VBAT < 4.92 V,
10 MΩ between PACK and DSG
TEST CONDITIONS
2.133
2.333
2.433
RatioCHG = (VCHG – VBAT)/VBAT, 2.2 V < VBAT < 4.92 V,
10 MΩ between BAT and CHG
2.133
2.333
2.433
10.5
11.5
12
10.5
11.5
12
—
VDSG(ON) = VDSG – VBAT, 4.92 V ≤ VBAT ≤ 18 V, 10 MΩ
between PACK and DSG
Output voltage,
CHG and DSG on VCHG(ON) = VCHG – VBAT, 4.92 V ≤ VBAT ≤ 18 V, 10 MΩ
between BAT and CHG
V
VDSG(OFF) = VDSG – VPACK, 10 MΩ between PACK and
Output voltage,
DSG
CHG and DSG off
VCHG(OFF) = VCHG – VBAT, 10 MΩ between BAT and CHG
Rise time
–0.4
0.4
–0.4
0.4
VDSG from 0% to 35% VDSG(ON)(TYP), VBAT ≥ 2.2 V, CL =
4.7 nF between DSG and PACK, 5.1 kΩ between DSG
and CL, 10 MΩ between PACK and DSG
200
500
VCHG from 0% to 35% VCHG(ON)(TYP), VBAT ≥ 2.2 V, CL =
4.7 nF between CHG and BAT, 5.1 kΩ between CHG
and CL, 10 MΩ between BAT and CHG
200
500
Submit Documentation Feedback
UNIT
V
µs
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
bq4050
www.ti.com
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
Electrical Characteristics: CHG, DSG FET Drive (continued)
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
PARAMETER
tF
TEST CONDITIONS
Fall time
TYP
MAX
VDSG from VDSG(ON)(TYP) to 1 V, VBAT ≥ 2.2 V, CL = 4.7 nF
between DSG and PACK, 5.1 kΩ between DSG and CL,
10 MΩ between PACK and DSG
MIN
40
300
VCHG from VCHG(ON)(TYP) to 1 V, VBAT ≥ 2.2 V, CL = 4.7
nF between CHG and BAT, 5.1 kΩ between CHG and
CL, 10 MΩ between BAT and CHG
40
200
UNIT
µs
6.19 Electrical Characteristics: PCHG FET Drive
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
PARAMETER
TEST CONDITIONS
V(FETON)
Output voltage,
PCHG on
VPCHG(ON) = VVCC – VPCHG, 10 MΩ between VCC and
PCHG
V(FETOFF)
Output voltage,
PCHG off
VPCHG(OFF) = VVCC – VPCHG, 10 MΩ between VCC and
PCHG
tR
Rise time
VPCHG from 10% to 90% VPCHG(ON)(TYP), VVCC ≥ 8 V, CL =
4.7 nF between PCHG and VCC, 5.1 kΩ between PCHG
and CL, 10 MΩ between VCC and CHG
tF
Fall time
VPCHG from 90% to 10% VPCHG(ON)(TYP), VCC ≥ 8 V, CL =
4.7 nF between PCHG and VCC, 5.1 kΩ between PCHG
and CL, 10 MΩ between VCC and CHG
MIN
TYP
MAX
6
7
8
V
0.4
V
40
200
µs
40
200
µs
–0.4
UNIT
6.20 Electrical Characteristics: FUSE Drive
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
PARAMETER
VOH
Output voltage
high
VIH
High-level input
IAFEFUSE(PU)
Internal pullup
current
RAFEFUSE
Output impedance
CIN
Input capacitance
tDELAY
Fuse trip detection
delay
tRISE
Fuse output rise
time
MIN
TYP
MAX
VBAT ≥ 8 V, CL = 1 nF, IAFEFUSE = 0 µA
TEST CONDITIONS
6
7
8.65
VBAT < 8 V, CL = 1 nF, IAFEFUSE = 0 µA
VBAT – 0.1
1.5
VBAT ≥ 8 V, VAFEFUSE = VSS
2
UNIT
V
VBAT
2.0
2.5
V
150
330
nA
2.6
3.2
kΩ
5
128
VBAT ≥ 8 V, CL = 1 nF, VOH = 0 V to 5 V
5
pF
256
µs
20
µs
6.21 Electrical Characteristics: Internal Temperature Sensor
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
PARAMETER
VTEMP
TEST CONDITIONS
MIN
TYP
MAX
Internal temperature VTEMPP
sensor voltage drift VTEMPP – VTEMPN, assured by design
–1.9
–2.0
–2.1
0.177
0.178
0.179
UNIT
mV/°C
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
13
bq4050
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
www.ti.com
6.22 Electrical Characteristics: TS1, TS2, TS3, TS4
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
TS1, TS2, TS3, TS4, VBIAS = VREF1
–0.2
0.8 × VREF1
TS1, TS2, TS3, TS4, VBIAS = VREG
–0.2
0.8 × VREG
UNIT
VIN
Input voltage
range
RNTC(PU)
Internal pullup
resistance
TS1, TS2, TS3, TS4
14.4
18
21.6
kΩ
RNTC(DRIFT)
Resistance drift
over temperature
TS1, TS2, TS3, TS4
–360
–280
–200
PPM/°C
V
6.23 Electrical Characteristics: PTC, PTCEN
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
PARAMETER
RPTC(TRIP)
PTC trip resistance
VPTC(TRIP)
PTC trip voltage
IPTC
Internal PTC
current bias
tPTC(DELAY)
PTC delay time
TEST CONDITIONS
MIN
TYP
MAX
UNIT
1.2
2.5
3.95
MΩ
VPTC(TRIP) = VPTCEN – VPTC
200
500
890
mV
TA = –40°C to 110°C
200
290
350
nA
TA = –40°C to 110°C
40
80
145
ms
6.24 Electrical Characteristics: Internal 1.8-V LDO
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
1.6
1.8
2.0
VREG
Regulator voltage
ΔVO(TEMP)
Regulator output
over temperature
ΔVREG/ΔTA, IREG = 10 mA
ΔVO(LINE)
Line regulation
ΔVREG/ΔVBAT, VBAT = 10 mA
–0 .6%
0.5%
ΔVO(LOAD)
Load regulation
ΔVREG/ΔIREG, IREG = 0 mA to 10 mA
–1.5%
1.5%
IREG
Regulator output
current limit
VREG = 0.9 × VREG(NOM), VIN > 2.2 V
20
ISC
Regulator shortcircuit current limit
VREG = 0 × VREG(NOM)
25
PSRRREG
Power supply
rejection ratio
ΔVBAT/ΔVREG, IREG = 10 mA ,VIN > 2.5 V, f = 10 Hz
VSLEW
Slew rate
enhancement
voltage threshold
VREG
UNIT
V
±0.25%
1.58
mA
40
55
mA
40
dB
1.65
V
6.25 Electrical Characteristics: High-Frequency Oscillator
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
PARAMETER
fHFO
Operating frequency
fHFO(ERR)
Frequency error
tHFO(SU)
Start-up time
TEST CONDITIONS
TYP
MAX
16.78
–2.5%
±0.25%
2.5%
TA = –40°C to 85°C, includes frequency drift
–3.5%
±0.25%
3.5%
TA = –20°C to 85°C, oscillator frequency within
+/–3% of nominal
Submit Documentation Feedback
UNIT
MHz
TA = –20°C to 70°C, includes frequency drift
oscillator frequency within +/–3% of nominal
14
MIN
4
ms
100
µs
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
bq4050
www.ti.com
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
6.26 Electrical Characteristics: Low-Frequency Oscillator
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
PARAMETER
fLFO
Operating frequency
fLFO(ERR)
Frequency error
fLFO(FAIL)
Failure detection
frequency
TEST CONDITIONS
MIN
TYP
MAX
UNIT
262.144
kHz
TA = –20°C to 70°C, includes frequency drift
–1.5%
±0.25%
1.5%
TA = –40°C to 85°C, includes frequency drift
–2.5
±0.25
2.5
30
80
100
kHz
6.27 Electrical Characteristics: Voltage Reference 1
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
PARAMETER
VREF1
Internal reference
voltage
VREF1(DRIFT)
Internal reference
voltage drift
TEST CONDITIONS
TA = 25°C, after trim
MIN
TYP
MAX
UNIT
1.21
1.215
1.22
V
TA = 0°C to 60°C, after trim
±50
TA = –40°C to 85°C, after trim
±80
PPM/°C
6.28 Electrical Characteristics: Voltage Reference 2
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
PARAMETER
VREF2
Internal reference
voltage
VREF2(DRIFT)
Internal reference
voltage drift
TEST CONDITIONS
TA = 25°C, after trim
MIN
TYP
MAX
UNIT
1.22
1.225
1.23
V
TA = 0°C to 60°C, after trim
±50
TA = –40°C to 85°C, after trim
±80
PPM/°C
6.29 Electrical Characteristics: Instruction Flash
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
PARAMETER
TEST CONDITIONS
Data retention
Flash programming
write cycles
MIN
TYP
MAX
UNIT
10
Years
1000
Cycles
tPROGWORD
Word programming
time
TA = –40°C to 85°C
40
µs
tMASSERASE
Mass-erase time
TA = –40°C to 85°C
40
ms
tPAGEERASE
Page-erase time
TA = –40°C to 85°C
40
ms
IFLASHREAD
Flash-read current
TA = –40°C to 85°C
2
mA
IFLASHWRITE
Flash-write current
TA = –40°C to 85°C
5
mA
IFLASHERASE
Flash-erase current
TA = –40°C to 85°C
15
mA
6.30 Electrical Characteristics: Data Flash
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
PARAMETER
TEST CONDITIONS
Data retention
Flash programming
write cycles
tPROGWORD
Word programming
time
TA = –40°C to 85°C
MIN
TYP
MAX
UNIT
10
Years
20000
Cycles
40
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
µs
15
bq4050
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
www.ti.com
Electrical Characteristics: Data Flash (continued)
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
tMASSERASE
Mass-erase time
TA = –40°C to 85°C
40
ms
tPAGEERASE
Page-erase time
TA = –40°C to 85°C
40
ms
IFLASHREAD
Flash-read current
TA = –40°C to 85°C
1
mA
IFLASHWRITE
Flash-write current
TA = –40°C to 85°C
5
mA
IFLASHERASE
Flash-erase current
TA = –40°C to 85°C
15
mA
6.31 Electrical Characteristics: OCD, SCC, SCD1, SCD2 Current Protection Thresholds
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
PARAMETER
OCD detection
threshold voltage range VOCD = VSRP – VSRN, AFE PROTECTION
CONTROL[RSNS] = 0
VOCD
OCD detection
threshold voltage
program step
ΔVOCD
SCC detection
threshold voltage
program step
ΔVSCC
SCD1 detection
threshold voltage
program step
ΔVSCD1
SCD2 detection
threshold voltage
program step
ΔVSCD2
VOFFSET
OCD, SCC, and SCDx
offset error
VSCALE
OCD, SCC, and SCDx
scale error
–100
–8.3
–50
mV
44.4
200
22.2
100
mV
VSCC = VSRP – VSRN, AFE PROTECTION
CONTROL[RSNS] = 1
22.2
VSCC = VSRP – VSRN, AFE PROTECTION
CONTROL[RSNS] = 0
11.1
mV
–44.4
–200
–22.2
–100
mV
VSCD1 = VSRP – VSRN, AFE PROTECTION
CONTROL[RSNS] = 1
–22.2
VSCD1 = VSRP – VSRN, AFE PROTECTION
CONTROL[RSNS] = 0
–11.1
mV
–44.4
–200
–22.2
–100
mV
VSCD2 = VSRP – VSRN, AFE PROTECTION
CONTROL[RSNS] = 1
–22.2
VSCD2 = VSRP – VSRN, AFE PROTECTION
CONTROL[RSNS] = 0
–11.1
No trim
Post-trim
Submit Documentation Feedback
UNIT
mV
–2.78
Post-trim
MAX
–16.6
VOCD = VSRP – VSRN, AFE PROTECTION
CONTROL[RSNS] = 0
VSCD2 = VSRP – VSRN, AFE PROTECTION
CONTROL[RSNS] = 1
SCD2 detection
threshold voltage range VSCD2 = VSRP – VSRN, AFE PROTECTION
CONTROL[RSNS] = 0
VSCD2
TYP
–5.56
VSCD1 = VSRP – VSRN, AFE PROTECTION
CONTROL[RSNS] = 1
SCD1 detection
threshold voltage range VSCD1 = VSRP – VSRN, AFE PROTECTION
CONTROL[RSNS] = 0
VSCD1
MIN
VOCD = VSRP – VSRN, AFE PROTECTION
CONTROL[RSNS] = 1
VSCC = VSRP – VSRN, AFE PROTECTION
CONTROL[RSNS] = 1
SCC detection
threshold voltage range VSCC = VSRP – VSRN, AFE PROTECTION
CONTROL[RSNS] = 0
VSCC
16
TEST CONDITIONS
VOCD = VSRP – VSRN, AFE PROTECTION
CONTROL[RSNS] = 1
mV
–2.5
2.5
–10%
10%
–5%
5%
mV
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
bq4050
www.ti.com
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
6.32 Timing Requirements: OCD, SCC, SCD1, SCD2 Current Protection Timing
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
MIN
NOM
MAX
tOCD
OCD detection
delay time
ΔtOCD
OCD detection
delay time
program step
tSCC
SCC detection
delay time
ΔtSCC
SCC detection
delay time
program step
tSCD1
SCD1 detection
delay time
AFE PROTECTION CONTROL[SCDDx2] = 0
0
915
AFE PROTECTION CONTROL[SCDDx2] = 1
0
1850
SCD1 detection
delay time
program step
AFE PROTECTION CONTROL[SCDDx2] = 0
61
ΔtSCD1
AFE PROTECTION CONTROL[SCDDx2] = 1
121
tSCD2
SCD2 detection
delay time
AFE PROTECTION CONTROL[SCDDx2] = 0
0
458
AFE PROTECTION CONTROL[SCDDx2] = 1
0
915
SCD2 detection
delay time
program step
AFE PROTECTION CONTROL[SCDDx2] = 0
30.5
ΔtSCD2
AFE PROTECTION CONTROL[SCDDx2] = 1
61
tDETECT
Current fault
detect time
VSRP – VSRN = VT – 3 mV for OCD, SCD1, and SC2,
VSRP – VSRN = VT + 3 mV for SCC
tACC
Current fault
delay time
accuracy
Max delay setting
1
31
2
0
ms
ms
915
61
µs
µs
µs
µs
µs
µs
160
–10%
UNIT
µs
10%
6.33 Timing Requirements: SMBus
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
MIN
NOM
10
MAX
UNIT
100
kHz
fSMB
SMBus operating frequency SLAVE mode, SMBC 50% duty cycle
fMAS
SMBus master clock
frequency
tBUF
Bus free time between start
and stop
4.7
µs
tHD(START)
Hold time after (repeated)
start
4.0
µs
tSU(START)
Repeated start setup time
4.7
µs
tSU(STOP)
Stop setup time
4.0
µs
tHD(DATA)
Data hold time
300
ns
tSU(DATA)
Data setup time
250
ns
tTIMEOUT
Error signal detect time
25
tLOW
Clock low period
4.7
tHIGH
Clock high period
4.0
tR
Clock rise time
tF
Clock fall time
tLOW(SEXT)
Cumulative clock low slave
extend time
tLOW(MEXT)
Cumulative clock low
master extend time
MASTER mode, no clock low slave extend
51.2
kHz
35
ms
µs
50
µs
10% to 90%
1000
ns
90% to 10%
300
ns
25
ms
10
ms
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
17
bq4050
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
www.ti.com
6.34 Timing Requirements: SMBus XL
Typical values stated where TA = 25°C and VCC = 14.4 V, Min/Max values stated where TA = –40°C to 85°C and VCC =
2.2 V to 26 V (unless otherwise noted)
MIN
SLAVE mode
NOM
MAX
UNIT
400
kHz
fSMBXL
SMBus XL operating
frequency
tBUF
Bus free time between start
and stop
4.7
µs
tHD(START)
Hold time after (repeated) start
4.0
µs
tSU(START)
Repeated start setup time
4.7
µs
tSU(STOP)
Stop setup time
4.0
tTIMEOUT
Error signal detect time
tLOW
tHIGH
40
µs
5
20
ms
Clock low period
20
µs
Clock high period
20
µs
TtR
tSU(STOP)p
TtF
TtF
tHD(START)
TtBUFT
SMBC
SMBC
SMBD
SMBD
P
TtR
TtHIGHT
TtLOWT
S
tHD(DATA)T
Start and Stop Condition
TtSU(DATA)
Wait and Hold Condition
tSU(START)T
TtTIMEOUT
SMBC
SMBC
SMBD
SMBD
S
Timeout Condition
Repeated Start Condition
Figure 4. SMBus Timing Diagram
18
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
bq4050
www.ti.com
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
6.35 Typical Characteristics
0.15
8.0
Max CC Offset Error
Min CC Offset Error
6.0
ADC Offset Error (µV)
CC Offset Error ( V)
0.10
0.05
0.00
±0.05
±0.10
4.0
2.0
0.0
±2.0
±4.0
±6.0
±0.15
Max ADC Offset Error
Min ADC Offset Error
±8.0
±40
±20
0
20
40
60
80
100
Temperature (ƒC)
120
±40
Figure 5. CC Offset Error vs. Temperature
20
40
60
80
100
120
C003
Figure 6. ADC Offset Error vs. Temperature
264
Low-Frequency Oscillator (kHz)
Reference Voltage (V)
0
Temperature (°C)
1.24
1.23
1.22
1.21
1.20
262
260
258
256
254
252
250
±40
0
±20
20
40
60
80
Temperature (ƒC)
100
±40
0
±20
20
40
60
80
Temperature (ƒC)
C006
Figure 7. Reference Voltage vs. Temperature
100
C007
Figure 8. Low-Frequency Oscillator vs. Temperature
16.9
±24.6
OCD Protection Threshold (mV)
High-Frequency Oscillator (MHz)
±20
C001
16.8
16.7
16.6
±24.8
±25.0
±25.2
±25.4
±25.6
±25.8
±40
±20
0
20
40
60
Temperature (ƒC)
80
100
120
±40
±20
0
20
40
60
80
100
Temperature (ƒC)
C008
120
C009
Threshold setting is –25 mV.
Figure 9. High-Frequency Oscillator vs. Temperature
Figure 10. Overcurrent Discharge Protection Threshold vs.
Temperature
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
19
bq4050
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
www.ti.com
Typical Characteristics (continued)
±86.0
SCD 1 Protection Threshold (mV)
SCC Protection Threshold (mV)
87.4
87.2
87.0
86.8
86.6
86.4
86.2
±86.2
±86.4
±86.6
±86.8
±87.0
±87.2
±40
±20
0
20
40
60
80
100
Temperature (ƒC)
120
±40
±20
0
C010
Threshold setting is 88.85 mV.
20
40
60
80
100
Temperature (ƒC)
120
C011
Threshold setting is –88.85 mV.
Figure 11. Short Circuit Charge Protection Threshold vs.
Temperature
Figure 12. Short Circuit Discharge 1 Protection Threshold
vs. Temperature
±172.9
Over-Current Delay Time (mS)
SCD 2 Protection Threshold (mV)
11.00
±173.0
±173.1
±173.2
±173.3
±173.4
±173.5
10.95
10.90
10.85
10.80
10.75
10.70
±173.6
±40
±20
0
20
40
60
80
100
Temperature (ƒC)
120
±40
Threshold setting is –177.7 mV.
20
40
60
80
100
120
C013
Threshold setting is 11 ms.
Figure 14. Overcurrent Delay Time vs. Temperature
480
452
450
SC Discharge 1 Delay Time ( S)
SC Charge Current Delay Time ( S)
0
Temperature (ƒC)
Figure 13. Short Circuit Discharge 2 Protection Threshold
vs. Temperature
448
446
444
442
440
438
436
434
432
460
440
420
400
±40
±20
0
20
40
60
Temperature (ƒC)
80
100
120
±40
±20
0
20
40
60
80
Temperature (ƒC)
C014
Threshold setting is 465 µs.
100
120
C015
Threshold setting is 465 µs (including internal delay).
Figure 15. Short Circuit Charge Current Delay Time vs.
Temperature
20
±20
C012
Figure 16. Short Circuit Discharge 1 Delay Time vs.
Temperature
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
bq4050
www.ti.com
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
Typical Characteristics (continued)
3.49825
2.4984
2.49835
3.4982
Cell Voltage (V)
Cell Voltage (V)
2.4983
2.49825
2.4982
2.49815
2.4981
3.49815
3.4981
3.49805
2.49805
3.498
2.498
±40
±20
0
20
40
60
80
100
Temperature (ƒC)
120
±40
±20
0
20
40
60
80
100
Temperature (ƒC)
C016
120
C017
This is the VCELL average for single cell.
Figure 17. VCELL Measurement at 2.5-V vs. Temperature
Figure 18. VCELL Measurement at 3.5-V vs. Temperature
4.24805
Measurement Current (mA)
99.25
Cell Voltage (V)
4.248
4.24795
4.2479
4.24785
4.2478
99.20
99.15
99.10
99.05
99.00
±40
±20
0
20
40
60
Temperature (ƒC)
80
100
120
±40
0
20
40
60
80
100
Temperature (ƒC)
C018
This is the VCELL average for single cell.
±20
120
C019
ISET = 100 mA
Figure 19. VCELL Measurement at 4.25-V vs. Temperature
Figure 20. I Measured vs. Temperature
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
21
bq4050
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
www.ti.com
7 Detailed Description
7.1 Overview
The bq4050 device, incorporating Compensated End-of-Discharge Voltage (CEDV) technology, provides cell
balancing while charging or at rest. This fully integrated, single-chip, pack-based solution, including a diagnostic
lifetime data monitor and black box recorder, provides a rich array of features for gas gauging, protection, and
authentication for 1-series, 2-series, 3-series, and 4-series cell Li-Ion and Li-Polymer battery packs.
Cell Detach
Detection
Wake
Comparator
PCHG
DSG
CHG
PBI
VCC
BAT
VSS
Cell, Stack,
Pack
Voltage
PACK
VC2
VC1
VC4
Cell
Balancing
VC3
7.2 Functional Block Diagram
Power Mode
Control
High Side
N-CH FET
Drive
P-CH
FET Drive
Power On
Reset
Zero Volt
Charge
Control
PTC
Overtemp
Short Circuit
Comparator
PTCEN
PTC
FUSE
Control
FUSE
High
Voltage
I/O
PRES or SHUTDN
SRP
SRN
Over
Current
Comparator
Voltage
Reference2
NTC Bias
Random
Number
Generator
Watchdog
Timer
Internal
Temp
Sensor
LED Display
Drive I/O
TS1
TS2
TS3
ADC/CC
FRONTEND
ADC MUX
DISP
LEDCNTLC
LEDCNTLB
LEDCNTLA
TS4
Voltage
Reference1
BTP_INT
AFE Control
Low
Frequency
Oscillator
1.8V LDO
Regulator
AFE COM
Engine
SBS High
Voltage
Translation
I/O &
Interrupt
Controller
AFE COM
Engine
SBS COM
Engine
SMBD
SMBC
High
Frequency
Oscillator
Low Voltage
I/O
I/O
ADC/CC
Digital Filter
Data (8bit)
bqBMP
CPU
PMInstr
(8bit)
Timers &
PWM
DMAddr (16bit)
PMAddr
(16bit)
Program
Flash
EEPROM
Data Flash
EEPROM
Data
SRAM
Copyright © 2017, Texas Instruments Incorporated
22
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
bq4050
www.ti.com
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
7.3 Feature Description
7.3.1 Primary (1st Level) Safety Features
The bq4050 gas gauge supports a wide range of battery and system protection features that can easily be
configured. See the bq4050 Technical Reference Manual (SLUUAQ3) for detailed descriptions of each protection
function.
The primary safety features include:
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Cell Overvoltage Protection
Cell Undervoltage Protection
Overcurrent in Charge Protection
Overcurrent in Discharge Protection
Overload in Discharge Protection
Short Circuit in Charge Protection
Short Circuit in Discharge Protection
Overtemperature in Charge Protection
Overtemperature in Discharge Protection
Undertemperature in Charge Protection
Undertemperature in Discharge Protection
Overtemperature FET protection
Precharge Timeout Protection
Host Watchdog Timeout Protection
Overcharge Protection
Overcharging Voltage Protection
Overcharging Current Protection
Over Precharge Current Protection
7.3.2 Secondary (2nd Level) Safety Features
The secondary safety features of the bq4050 gas gauge can be used to indicate more serious faults via the
FUSE pin. This pin can be used to blow an in-line fuse to permanently disable the battery pack from charging or
discharging. See the bq4050 Technical Reference Manual (SLUUAQ3) for detailed descriptions of each
protection function.
The secondary safety features provide protection against:
• Safety Overvoltage Permanent Failure
• Safety Undervoltage Permanent Failure
• Safety Overtemperature Permanent Failure
• Safety FET Overtemperature Permanent Failure
• Fuse Failure Permanent Failure
• PTC Permanent Failure
• Voltage Imbalance at Rest (VIMR) Permanent Failure
• Voltage Imbalance Active (VIMA) Permanent Failure
• Charge FET Permanent Failure
• Discharge FET Permanent Failure
• AFE Register Permanent Failure
• AFE Communication Permanent Failure
• Second Level Protector Permanent Failure
• Instruction Flash Checksum Permanent Failure
• Open Cell Connection Permanent Failure
• Data Flash Permanent Failure
• Open Thermistor Permanent Failure
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
23
bq4050
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
www.ti.com
Feature Description (continued)
7.3.3 Charge Control Features
The bq4050 gas gauge charge control features include:
•
•
•
•
•
•
•
Supports JEITA temperature ranges. Reports charging voltage and charging current according to the active
temperature range
Handles more complex charging profiles. Allows for splitting the standard temperature range into two
subranges and allows for varying the charging current according to the cell voltage
Reports the appropriate charging current needed for constant current charging and the appropriate charging
voltage needed for constant voltage charging to a smart charger using SMBus broadcasts
Reduces the charge difference of the battery cells in fully charged state of the battery pack gradually using a
voltage-based cell balancing algorithm during charging. A voltage threshold can be set up for cell balancing to
be active. This prevents fully charged cells from overcharging and causing excessive degradation and also
increases the usable pack energy by preventing premature charge termination.
Supports precharging/0-volt charging
Supports charge inhibit and charge suspend if the battery pack temperature is out of temperature range
Reports charging fault and also indicates charge status via charge and discharge alarms
7.3.4 Gas Gauging
The bq4050 gas gauge uses the Compensated End-of-Discharge Voltage (CEDV) algorithm to measure and
calculate the available capacity in battery cells. The bq4050 device accumulates a measure of charge and
discharge currents, estimates self-discharge of the battery, and adjusts the self-discharge estimation based on
temperature. See the bq4050 Technical Reference Manual (SLUUAQ3) for further details.
7.3.5 Configuration
7.3.5.1 Oscillator Function
The bq4050 gas gauge fully integrates the system oscillators and does not require any external components to
support this feature.
7.3.5.2 System Present Operation
The bq4050 gas gauge checks the PRES pin periodically (1 s). If PRES input is pulled to ground by the external
system, the bq4050 device detects this as system present.
7.3.5.3 Emergency Shutdown
For battery maintenance, the emergency shutdown feature enables a push button action connecting the
SHUTDN pin to shut down an embedded battery pack system before removing the battery. A high-to-low
transition of the SHUTDN pin signals the bq4050 gas gauge to turn off the CHG and DSG FETs, disconnecting
the power from the system to safely remove the battery pack. The CHG and DSG FETs can be turned on again
by another high-to-low transition detected by the SHUTDN pin or when a data flash configurable timeout is
reached.
7.3.5.4 1-Series, 2-Series, 3-Series, or 4-Series Cell Configuration
In a 1-series cell configuration, VC4 is shorted to VC, VC2, and VC1. In a 2-series cell configuration, VC4 is
shorted to VC3 and VC2. In a 3-series cell configuration, VC4 is shorted to VC3.
7.3.5.5 Cell Balancing
The device reduces the charge difference of the battery cells in a fully charged state of the battery pack by
gradually using a voltage-based cell balancing algorithm during charging. A voltage threshold can be set up for
cell balancing to be active. This prevents fully charged cells from overcharging and causing excessive
degradation, and increases the usable pack energy by preventing premature charge termination.
24
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
bq4050
www.ti.com
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
Feature Description (continued)
7.3.6 Battery Parameter Measurements
7.3.6.1 Charge and Discharge Counting
The bq4050 gas gauge uses an integrating delta-sigma analog-to-digital converter (ADC) for current
measurement, and a second delta-sigma ADC for individual cell and battery voltage and temperature
measurement.
The integrating delta-sigma ADC measures the charge/discharge flow of the battery by measuring the voltage
drop across a small-value sense resistor between the SRP and SRN terminals. The integrating ADC measures
bipolar signals from –0.1 V to 0.1 V. The bq4050 gauge detects charge activity when VSR = V(SRP) – V(SRN) is
positive, and discharge activity when VSR = V(SRP) – V(SRN) is negative. The bq4050 gas gauge continuously
integrates the signal over time, using an internal counter. The fundamental rate of the counter is 0.26 nVh.
7.3.7 Battery Trip Point (BTP)
Required for WIN8 OS, the battery trip point (BTP) feature indicates when the RSOC of a battery pack has
depleted to a certain value set in a DF register. This feature enables a host to program two capacity-based
thresholds that govern the triggering of a BTP interrupt on the BTP_INT pin and the setting or clearing of the
OperationStatus[BTP_INT] on the basis of RemainingCapacity().
An internal weak pullup is applied when the BTP feature is active. Depending on the system design, an external
pullup may be required to put on the BTP_INT pin. See Electrical Characteristics: PRES, BTP_INT, DISP for
details.
7.3.8 Lifetime Data Logging Features
The bq4050 gas gauge offers lifetime data logging for several critical battery parameters. The following
parameters are updated every 10 hours if a difference is detected between values in RAM and data flash:
• Maximum and Minimum Cell Voltages
• Maximum Delta Cell Voltage
• Maximum Charge Current
• Maximum Discharge Current
• Maximum Average Discharge Current
• Maximum Average Discharge Power
• Maximum and Minimum Cell Temperature
• Maximum Delta Cell Temperature
• Maximum and Minimum Internal Sensor Temperature
• Maximum FET Temperature
• Number of Safety Events Occurrences and the Last Cycle of the Occurrence
• Number of Valid Charge Termination and the Last Cycle of the Valid Charge Termination
• Number of Shutdown Events
• Cell Balancing Time for Each Cell
(This data is updated every 2 hours if a difference is detected.)
• Total FW Runtime and Time Spent in Each Temperature Range
(This data is updated every 2 hours if a difference is detected.)
7.3.9 Authentication
The bq4050 gas gauge supports authentication by the host using SHA-1.
7.3.10 LED Display
The bq4050 gas gauge can drive a 3-, 4-, or 5- segment LED display for remaining capacity indication and/or a
permanent fail (PF) error code indication.
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
25
bq4050
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
www.ti.com
Feature Description (continued)
7.3.11 Voltage
The bq4050 gas gauge updates the individual series cell voltages at 0.25-s intervals. The internal ADC of the
bq4050 device measures the voltage, and scales and calibrates it appropriately. This data is also used to
calculate the impedance of the cell for the CEDV gas gauging.
7.3.12 Current
The bq4050 gas gauge uses the SRP and SRN inputs to measure and calculate the battery charge and
discharge current using a 1-mΩ to 3-mΩ typ. sense resistor.
7.3.13 Temperature
The bq4050 gas gauge has an internal temperature sensor and inputs for four external temperature sensors. All
five temperature sensor options can be individually enabled and configured for cell or FET temperature usage.
Two configurable thermistor models are provided to enable monitoring of the cell temperature in addition to the
FET temperature, which use a different thermistor profile.
7.3.14 Communications
The bq4050 gas gauge uses SMBus v1.1 with MASTER mode and packet error checking (PEC) options per the
SBS specification.
7.3.14.1 SMBus On and Off State
The bq4050 gas gauge detects an SMBus off state when SMBC and SMBD are low for two or more seconds.
Clearing this state requires that either SMBC or SMBD transition high. The communication bus will resume
activity within 1 ms.
7.3.14.2 SBS Commands
See the bq4050 Technical Reference Manual (SLUUAQ3) for further details.
7.4 Device Functional Modes
The bq4050 gas gauge supports three power modes to reduce power consumption:
• In NORMAL mode, the bq4050 gauge performs measurements, calculations, protection decisions, and data
updates in 250-ms intervals. Between these intervals, the bq4050 gauge is in a reduced power stage.
• In SLEEP mode, the bq4050 gauge performs measurements, calculations, protection decisions, and data
updates in adjustable time intervals. Between these intervals, the bq4050 gauge is in a reduced power stage.
The bq4050 gauge has a wake function that enables exit from SLEEP mode when current flow or failure is
detected.
• In SHUTDOWN mode, the bq4050 gauge is completely disabled.
26
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
bq4050
www.ti.com
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
8 Applications and Implementation
NOTE
Information in the following applications sections is not part of the TI component
specification, and TI does not warrant its accuracy or completeness. TI’s customers are
responsible for determining suitability of components for their purposes. Customers should
validate and test their design implementation to confirm system functionality.
8.1 Application Information
The bq4050 gas gauge has primary protection support to be used with a 1-series to 4-series Li-Ion/Li Polymer
battery pack. To implement and design a comprehensive set of parameters for a specific battery pack, users
need the Battery Management Studio (bqStudio) graphical user-interface tool installed on a PC during
development. The firmware installed on the bqStudio tool has default values for this product, which are
summarized in the bq4050 Technical Reference Manual (SLUUAQ3). Using the bqStudio tool, these default
values can be changed to cater to specific application requirements during development once the system
parameters, such as fault trigger thresholds for protection, enable/disable of certain features for operation,
configuration of cells, chemistry that best matches the cell used, and more are known. This data is referred to as
the "golden image."
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
27
bq4050
4P
J1
1
2
3
1
2
1
R11
100
R13
1K
R14
0.1uF
C4
C5
0.1uF
1
2
3
4
CD 7
VSS 6
V1 5
U2
BQ2947xyDSG
VDD
OUT 8
V4
V3
V2
1
FUSE
C7
0.1uF 0.1uF
C6
F1
2
SFDxxxx
4P
10M
R2
300
R1
FUSEPIN
R6
0.1uF
C3
R16
5.1K
C13
51K
Q5
Si1406DH
3
BAT
D1
BAT54HT1
AGND
BAT
3
R17
5.1K
3
Q2
Si7116DN
R7
5.1K
CHG
SRP
NC
SRN
VC 1
VC 2
VC 3
VC 4
2.2uF
1 PBI
2
3
4
5
6
7
8
C1
0.1uF
C2
R9
2
0.1uF
Q1
FDN358P
R5
10M
R8
100
3
DSG
5.1K
RT3
GND
Q3
Si7116DN
R10
5.1K
10M
R3
23
24
10K
R12
PTCEN
PTC
20
21
22
19
17
18
Q4
2N7002K
1
10K
R4
C12
RT1
D8
LED2
D6
LED4
BAT
CHGND
D5
LED3
D7
LED1
0.1uF
2
10K
D9
LED5
4P
BAT
10K
R32
S1
Wake
PACK+
A
A'
5
4
3
2
1
B
B'
For Thumbus-SMB
SMBD
I2C_VOUT
CHGND
SMBC
CHGND
1K
R29
100
R25
D4
R24
D3
100
R27
D2
200
R26
200
2001
2
A
B
A'
B'
J7
S2
LED DISPLAY
GND
R28
B
B'
SHUTDOWN
A
A'
S3
DISP
SMBD
SMBC
LEDCNTLA
LEDCNTLB
LEDCNTLC
TP12
RT5
GND
RT4
10K
GND
10K
GND
J6
SMBC
SMBD
4
3
2
PACK+
J2
1
CHGND
C8
0.1uF
C10
0.1uF
SMBD
VSS
SMBC
2
1
3
2
1
J4
J3
PACK+
PACK+
Sys Pres
PACK-
PACK-
PACK+
CHGND
Product Folder Links: bq4050
1K
R15
GND
C15
C16
0.1uF
C17
GND
RT2
10K
GND
10K
GND
CHGND
GND SIDE
6
7
2
3
GND
MM3ZxxVyC
Copyright © 2017, Texas Instruments Incorporated
SMBD
C9
0.1uF
C11
0.1uF
0.1uF
C14
0.1uF
0.1uF
TP3
SRN
DNP
C20
C21
DNP
GND SIDE
1
GND SIDE
1K
R22
100
R23
C18
0.1uF
R31
25
4
100
GND
1
2
1
2
R18
R21
100
SRP
R30
R19
0.001
CHGND
1
1
1K
R20
100
100
GND
C19
DNP 100
GND
1
1
3P
2P
1P J5
1N
NT1
Net-Tie
IC ground should be connected to the 1N cell tab.
Replace D1 and R9 with a 10 ohm resistor for single cell applications
Place RT1 close to Q2 and Q3.
DSG
28
1
SMBC
SMBC
SMBD
1
2
1
2
GND SIDE
30
NC
29
CHG
3
2
1
FUSE
1 16 PRES or SHUTDN
VCC
1
4P
AGND GND
1
3
MM3ZxxVyC
5
PCHG
1
2
3
1
5
1
1
1
10 TS1
11 TS2
4
27
26
1
32
12 TS3
13 TS4
PACK
14 NC
15 BTP_INT
31
33
BAT
1
1
PWPD
VSS
9
Copyright © 2016–2017, Texas Instruments Incorporated
Submit Documentation Feedback
28
2
MM3ZxxVyC
1
1
1
1
1
1
3
6
4
1
1
1
EP
9
5
2
1
1
www.ti.com
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
8.2 Typical Applications
Figure 21. Application Schematic
bq4050
www.ti.com
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
Typical Applications (continued)
8.2.1 Design Requirements
Table 1 shows the default settings for the main parameters. Use the bqStudio tool to update the settings to meet
the specific application or battery pack configuration requirements.
The device should be calibrated before any gauging test. Follow the information in the bqStudio Calibration
page to calibrate the device, and use the bqStudio Chemistry page to update the match chemistry profile to the
device.
Table 1. Design Parameters
(1)
DESIGN PARAMETER
EXAMPLE
Cell Configuration
3s1p (3-series with 1 Parallel) (1)
Design Capacity
4400 mAh
Device Chemistry
1210 (LiCoO2/graphitized carbon)
Cell Overvoltage at Standard Temperature
4300 mV
Cell Undervoltage
2500 mV
Shutdown Voltage
2300 mV
Overcurrent in CHARGE Mode
6000 mA
Overcurrent in DISCHARGE Mode
–6000 mA
Short Circuit in CHARGE Mode
0.1 V/Rsense across SRP, SRN
Short Circuit in DISCHARGE Mode
0.1 V/Rsense across SRP, SRN
Safety Overvoltage
4500 mV
Cell Balancing
Disabled
Internal and External Temperature Sensor
External Temperature Sensors are used.
Undertemperature Charging
0°C
Undertemperature Discharging
0°C
BROADCAST Mode
Disabled
Battery Trip Point (BTP) with active high interrupt
Disabled
When using the device the first time, if the a 1-s or 2-s battery pack is used, then a charger or power supply should be connected to the
PACK+ terminal to prevent device shutdown. Then update the cell configuration (see the bq4050 Technical Reference Manual
(SLUUAQ3) for details) before removing the charger connection.
8.2.2 Detailed Design Procedure
8.2.2.1 High-Current Path
The high-current path begins at the PACK+ terminal of the battery pack. As charge current travels through the
pack, it finds its way through protection FETs, a chemical fuse, the lithium-ion cells and cell connections, and the
sense resistor, and then returns to the PACK– terminal (see Figure 22). In addition, some components are
placed across the PACK+ and PACK– terminals to reduce effects from electrostatic discharge.
8.2.2.1.1 Protection FETs
Select the N-CH charge and discharge FETs for a given application. Most portable battery applications are a
good match for the CSD17308Q3. The TI CSD17308Q3 is a 47A, 30-V device with Rds(on) of 8.2 mΩ when the
gate drive voltage is 8 V.
If a precharge FET is used, R1 is calculated to limit the precharge current to the desired rate. Be sure to account
for the power dissipation of the series resistor. The precharge current is limited to (VCHARGER – VBAT)/R1 and
maximum power dissipation is (Vcharger – Vbat)2/R1.
The gates of all protection FETs are pulled to the source with a high-value resistor between the gate and source
to ensure they are turned off if the gate drive is open.
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
29
bq4050
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
www.ti.com
Capacitors C1 and C2 help protect the FETs during an ESD event. Using two devices ensures normal operation
if one becomes shorted. To have good ESD protection, the copper trace inductance of the capacitor leads must
be designed to be as short and wide as possible. Ensure that the voltage ratings of C1 and C2 are adequate to
hold off the applied voltage if one of the capacitors becomes shorted.
C1
R1
0.1 F
C2
0.1 F
300
Q1
FDN358P
Q3
Si7114DN
Q2
Si7114DN
R2
10M
R5
R3
10M
Q4
2N7002K
10M
R4
10K
R7
5.1K
R8
5.1K
R9
100
R10
5.1K
Copyright © 2016, Texas Instruments Incorporated
Figure 22. bq4050 Protection FETs
8.2.2.1.2 Chemical Fuse
The chemical fuse (Dexerials, Uchihashi, and so on) is ignited under command from either the bq294700
secondary voltage protection IC or from the FUSE pin of the gas gauge. Either of these events applies a positive
voltage to the gate of Q5, shown in Figure 23, which then sinks current from the third terminal of the fuse,
causing it to ignite and open permanently.
It is important to carefully review the fuse specifications and match the required ignition current to that available
from the N-CH FET. Ensure that the proper voltage, current, and Rds(on) ratings are used for this device. The
fuse control circuit is discussed in detail in FUSE Circuitry.
30
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
bq4050
www.ti.com
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
4P
F1
DNP
1
2
6
5
2
1
3
Q5
Si1406DH
4
3
R6
51K
to 2nd Level Protector
R16
C3
0.1 F
5.1K
R17
5.1K
to FUSE Pin
Copyright © 2016, Texas Instruments Incorporated
Figure 23. FUSE Circuit
8.2.2.1.3 Lithium-Ion Cell Connections
The important part to remember about the cell connections is that high current flows through the top and bottom
connections; therefore, the voltage sense leads at these points must be made with a Kelvin connection to avoid
any errors due to a drop in the high-current copper trace. The location marked 4P in Figure 24 indicates the
Kelvin connection of the most positive battery node. The connection marked 1N is equally important. The VC5
pin (a ground reference for cell voltage measurement), which is in the older generation devices, is not in the
bq4050 device. Therefore, the single-point connection at 1N to the low-current ground is needed to avoid an
undesired voltage drop through long traces while the gas gauge is measuring the bottom cell voltage.
Figure 24. Lithium-Ion Cell Connections
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
31
bq4050
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
www.ti.com
8.2.2.1.4 Sense Resistor
As with the cell connections, the quality of the Kelvin connections at the sense resistor is critical. The sense
resistor must have a temperature coefficient no greater than 50 ppm in order to minimize current measurement
drift with temperature. Choose the value of the sense resistor to correspond to the available overcurrent and
short-circuit ranges of the bq4050 gauge. Select the smallest value possible to minimize the negative voltage
generated on the bq4050 VSS node(s) during a short circuit. This pin has an absolute minimum of –0.3 V. Parallel
resistors can be used as long as good Kelvin sensing is ensured. The device is designed to support a 1-mΩ to 3mΩ sense resistor.
The ground scheme of bq4050 gauge is different from the older generation devices. In previous devices, the
device ground (or low current ground) is connected to the SRN side of the Rsense resistor pad. The bq4050
gauge, however, it connects the low-current ground on the SRP side of the Rsense resistor pad close to the
battery 1N terminal (see Lithium-Ion Cell Connections). This is because the bq4050 gauge has one less VC pin
(a ground reference pin VC5) compared to the previous devices. The pin was removed and was internally
combined to SRP.
R19
0.001
50 ppm
Copyright © 2016 , Texas Instruments Incorporated
Figure 25. Sense Resistor
8.2.2.1.5 ESD Mitigation
A pair of series 0.1-μF ceramic capacitors is placed across the PACK+ and PACK– terminals to help in the
mitigation of external electrostatic discharges. The two devices in series ensure continued operation of the pack
if one of the capacitors becomes shorted.
Optionally, a tranzorb such as the SMBJ2A can be placed across the terminals to further improve ESD immunity.
8.2.2.2 Gas Gauge Circuit
The gas gauge circuit includes the bq4050 gauge and its peripheral components. These components are divided
into the following groups: Differential Low-Pass Filter, PBI, system present, SMBus Communication, FUSE
circuit, and LED.
8.2.2.2.1 Coulomb-Counting Interface
The bq4050 gauge uses an integrating delta-sigma ADC for current measurements. Add a 100-Ω resistor from
the sense resistor to the SRP and SRN inputs of the device. Place a 0.1-µF (C18) filter capacitor across the SRP
and SRN inputs. Optional 0.1-µF filter capacitors (C19 and C20) can be added for additional noise filtering if
required for a circuit.
32
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
bq4050
www.ti.com
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
C18
0.1 µF
C19
DNP
C20
DNP
R31
100
R30
100
R19
0.001
50 ppm
Copyright © 2016, Texas Instruments Incorporated
Figure 26. Differential Filter
8.2.2.2.2 Power Supply Decoupling and PBI
The bq4050 gauge has an internal LDO that is internally compensated and does not require an external
decoupling capacitor.
25
FUSE
27
VCC 26
PACK
DSG 28
29
NC
PCHG 30
BAT
PWPD
CHG 31
32
33
The PBI pin is used as a power supply backup input pin providing power during brief transient power outages. A
standard 2.2-µF ceramic capacitor is connected from the PBI pin to ground as shown in Figure 27.
1 PBI
C13
2.2 μF
PTCEN
24
23
2
VC4
PTC
3
VC3
LEDCNTL3
22
4
VC2
LEDCNTL2
21
5
VC1
LEDCNTL1 20
6 SRN
SMBC
7
SMBD
NC
19
18
DISP 17
PRES
16
1 5 NC
NC
14
TS4
13
TS2
TS3
12
11
TS1
10
9
vss
8 SRP
Copyright © 2016 , Texas Instruments Incorporated
Figure 27. Power Supply Decoupling
8.2.2.2.3 System Present
The system present signal is used to inform the gas gauge whether the pack is installed into or removed from the
system. In the host system, this pin is grounded. The PRES pin of the bq4050 gauge is occasionally sampled to
test for system present. To save power, an internal pullup is provided by the gas gauge during a brief 4-μs
sampling pulse once per second. A resistor can be used to pull the signal low and the resistance must be 20 kΩ
or lower to ensure that the test pulse is lower than the VIL limit. The pullup current source is typically 10 µA to
20 µA.
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
33
bq4050
16
PRES
BTP_IN
15
NC
www.ti.com
14
13
TS4
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
VIL
<20 K
GND
Copyright © 2016, Texas Instruments Incorporated
Figure 28. System Present Pull-Down Resistor
Because the system present signal is part of the pack connector interface to the outside world, it must be
protected from external electrostatic discharge events. An integrated ESD protection on the PRES device pin
reduces the external protection requirement to just R29 for an 8-kV ESD contact rating. However, if it is possible
that the system present signal may short to PACK+, then R28 and D4 must be included for high-voltage
protection.
34
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
bq4050
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
DSG 28
27
PACK
26
VCC
25
FUSE
www.ti.com
PTCEN
PTC
D5
24
23
22
LEDCNTL3
LEDCNTL2 21
LEDCNTL1 20
LED3
LED4
D9
D7
SMBC 19
SMBD 18
LED5
D8
LED1
17
LED2
R24
200
R25
100
R26
200
R27
100
4
TS4
14 NC
15
NC
16
PRES
DISP
D6
3
13
S2
A
A1
SMBD
2
B
B1
SMBC
1
VSS
J2
R28
R29
200
J3
1k
3
Sys Pres
2
D2
D3
D4
1
PACK+
1
GNDSIDE
MM3Z5V6C
GNDSIDE
MM3Z5V6C
GNDSIDE
MM3Z5V6C
GNDSIDE
2
PACK±
J4
Copyright © 2016, Texas Instruments Incorporated
Figure 29. System Present ESD and Short Protection
8.2.2.2.4 SMBus Communication
The SMBus clock and data pins have integrated high-voltage ESD protection circuits; however, adding a Zener
diode (D2 and D3) and series resistor (R24 and R26) provides more robust ESD performance.
The SMBus clock and data lines have internal pulldown. When the gas gauge senses that both lines are low
(such as during removal of the pack), the device performs auto-offset calibration and then goes into SLEEP
mode to conserve power.
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
35
bq4050
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
www.ti.com
R24
200
R25
100
R26
200
R27
100
4
3
SMBD
2
SMBC
1
VSS
J2
J3
R28
200
R29
1k
3
Sys Pres
2
D2
D3
D4
1
PACK+
1
PACK±
J4
GNDSIDE
MM3Z5V6C
GNDSIDE
MM3Z5V6C
GNDSIDE
MM3Z5V6C
GNDSIDE
2
Copyright © 2016, Texas Instruments Incorporated
Figure 30. ESD Protection for SMB Communication
8.2.2.2.5 FUSE Circuitry
The FUSE pin of the bq4050 gauge is designed to ignite the chemical fuse if one of the various safety criteria is
violated. The FUSE pin also monitors the state of the secondary-voltage protection IC. Q5 ignites the chemical
fuse when its gate is high. The 7-V output of the bq294700 is divided by R16 and R6, which provides adequate
gate drive for Q5 while guarding against excessive back current into the bq294700 if the FUSE signal is high.
Using C3 is generally a good practice, especially for RFI immunity. C3 may be removed, if desired, because the
chemical fuse is a comparatively slow device and is not affected by any submicrosecond glitches that come from
the FUSE output during the cell connection process.
4P
1
F1
DNP
2
6
5
2
1
3
Q5
4
3
Si1406DH
R6
51K
to 2nd Level Protector
R16
C3
0.1 F
5.1K
R17
5.1K
to FUSE Pin
Copyright © 2016, Texas Instruments Incorporated
Figure 31. FUSE Circuit
When the bq4050 gauge is commanded to ignite the chemical fuse, the FUSE pin activates to give a typical 8-V
output. The new design makes it possible to use a higher Vgs FET for Q5. This improves the robustness of the
system, as well as widens the choices for Q5.
36
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
bq4050
www.ti.com
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
8.2.2.3 Secondary-Current Protection
The bq4050 gauge provides secondary overcurrent and short-circuit protection, cell balancing, cell voltage
multiplexing, and voltage translation. The following discussion examines cell and battery inputs, pack and FET
control, temperature output, and cell balancing.
8.2.2.3.1 Cell and Battery Inputs
Each cell input is conditioned with a simple RC filter, which provides ESD protection during cell connect and acts
to filter unwanted voltage transients. The resistor value allows some trade-off for cell balancing versus safety
protection.
The integrated cell balancing FETs allow the AFE to bypass cell current around a given cell or numerous cells,
effectively balancing the entire battery stack. External series resistors placed between the cell connections and
the VCx I/O pins set the balancing current magnitude. The internal FETs provide a 200-Ω resistance (2 V < VDS
< 4 V). Series input resistors between 100 Ω and 1 kΩ are recommended for effective cell balancing.
The BAT input uses a diode (D1) to isolate and decouple it from the cells in the event of a transient dip in voltage
caused by a short-circuit event.
Also, as described in High-Current Path, the top and bottom nodes of the cells must be sensed at the battery
connections with a Kelvin connection to prevent voltage sensing errors caused by a drop in the high-current PCB
copper.
BAT54HT1
33
PWPD
32
BAT
D1
C14
C15
0.1 F
C16
C13
0.1 F
4P
3P
1
2
3
1
2
2P
1P
1N
C17
0.1 F
R20
100
R21
0.1 F
2.2 F
100
R22
100
R23
100
9 VSS
J5
1
PBI
2
VC4
3
VC3
4
VC2
5
VC1
6 SRN
7 NC
8
SRP
J1
Copyright © 2016, Texas Instruments Incorporated
Figure 32. Cell and BAT Inputs
8.2.2.3.2 External Cell Balancing
Internal cell balancing can only support up to 10 mA. External cell balancing is provided as another option for
faster cell balancing. For details, refer to the application note, Fast Cell Balancing Using External MOSFET
(SLUA420).
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
37
bq4050
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
www.ti.com
8.2.2.3.3 PACK and FET Control
The PACK and VCC inputs provide power to the bq4050 gauge from the charger. The PACK input also provides a
method to measure and detect the presence of a charger. The PACK input uses a 100-Ω resistor; whereas, the
VCC input uses a diode to guard against input transients and prevents misoperation of the date driver during
short-circuit events.
C1
R1
0.1 μF
C2
0.1 μF
300
Q1
FDN358 P
R2
10M
Q3
Si7114DN
Q2
Si7114 DN
R5
R3
10 M
Q4
2N7002 K
10 M
R4
10K
R7
5 .1K
R9
100
R10
5.1K
R12
10K
PWPD 33
32
BAT
3
CHG 1
30
P CHG
29
NC
28
DSG
27
PA CK
26
VCC
25
FUSE
R8
5 .1K
Copyright © 2016 , Texas Instruments Incorporated
Figure 33. bq4050 PACK and FET Control
The N-CH charge and discharge FETs are controlled with 5.1-kΩ series gate resistors, which provide a switching
time constant of a few microseconds. The 10-MΩ resistors ensure that the FETs are off in the event of an open
connection to the FET drivers. Q4 is provided to protect the discharge FET (Q3) in the event of a reverseconnected charger. Without Q4, Q3 can be driven into its linear region and suffer severe damage if the PACK+
input becomes slightly negative.
Q4 turns on in that case to protect Q3 by shorting its gate to source. To use the simple ground gate circuit, the
FET must have a low gate turn-on threshold. If it is desired to use a more standard device, such as the 2N7002
as the reference schematic, the gate should be biased up to 3.3 V with a high-value resistor. The bq4050 device
has the capability to provide a current-limited charging path typically used for low battery voltage or low
temperature charging. The bq4050 device uses an external P-channel, precharge FET controlled by PCHG.
8.2.2.3.4 Temperature Output
For the bq4050 device, TS1, TS2, TS3, and TS4 provide thermistor drive-under program control. Each pin can
be enabled with an integrated 18-kΩ (typical) linearization pullup resistor to support the use of a 10-kΩ at 25°C
(103) NTC external thermistor, such as a Mitsubishi BN35-3H103. The reference design includes four 10-kΩ
thermistors: RT1, RT2, RT3, and RT4. The bq4050 device supports up to four external thermistors. Connect
unused thermistor pins to VSS.
38
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
bq4050
16 PRES
NC
15 NC
14
13 TS4
12 TS3
11 TS2
9
10
VSS
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
TS1
www.ti.com
RT2
RT3
RT4
RT5
10 K
10 K
10 K
10 K
Copyright © 2016, Texas Instruments Incorporated
Figure 34. Thermistor Drive
8.2.2.3.5 LEDs
Three LED control outputs provide constant current sinks for the driving external LEDs. These outputs are
configured to provide voltage and control for up to 5 LEDs. No external bias voltage is required. Unused
LEDCNTL pins can remain open or they can be connected to VSS. The DISP pin should be connected to VSS, if
the LED feature is not used.
D5
D6
24
PTCEN
23
PTC
22
LEDCNTL3
LED3
LED4
21
LEDCNTL2
D9
20
LEDCNTL1
D7
D8
LED5
19
SMBC
18
SMBD
17
DISP
LED1
LED2
Copyright © 2016, Texas Instruments Incorporated
Figure 35. LEDs
8.2.2.3.6 Safety PTC Thermistor
The bq4050 device provides support for a safety PTC thermistor. The PTC thermistor is connected between PTC
and PTCEN, and PTCEN is connected to BAT. It can be placed close to the CHG/DSG FETs to monitor the
temperature. A PTC fault is one of the permanent failure modes. It can only be cleared by a POR.
To disable, connect PTC and PTCEN to VSS.
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
39
bq4050
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
www.ti.com
C12
PTCEN
24
23
PTC
LEDCNTL3 22
LEDCNTL2 21
0.1 F
RT1
10K
BAT
LEDCNTL1 20
SMBC 19
SMBD 18
DISP 17
Copyright © 2016, Texas Instruments Incorporated
Figure 36. PTC Thermistor
40
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
bq4050
www.ti.com
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
8.2.3 Application Curves
87.4
SCC Protection Threshold (mV)
OCD Protection Threshold (mV)
±24.6
±24.8
±25.0
±25.2
±25.4
±25.6
87.2
87.0
86.8
86.6
86.4
86.2
±25.8
±40
±20
0
20
40
60
80
100
Temperature (ƒC)
120
±40
±20
0
20
40
60
80
100
Temperature (ƒC)
C009
Threshold setting is –25 mV.
120
C010
Threshold setting is 88.85 mV.
Figure 37. Overcurrent Discharge Protection Threshold Vs.
Temperature
Figure 38. Short Circuit Charge Protection Threshold Vs.
Temperature
SCD 2 Protection Threshold (mV)
SCD 1 Protection Threshold (mV)
±86.0
±86.2
±86.4
±86.6
±86.8
±87.0
±172.9
±173.0
±173.1
±173.2
±173.3
±173.4
±173.5
±173.6
±87.2
±40
±20
0
20
40
60
80
100
Temperature (ƒC)
±40
120
0
20
40
60
80
100
Temperature (ƒC)
C011
120
C012
Threshold setting is –177.7 mV.
Threshold setting is –88.85 mV.
Figure 39. Short Circuit Discharge 1 Protection Threshold
Vs. Temperature
Figure 40. Short Circuit Discharge 2 Protection Threshold
Vs. Temperature
452
SC Charge Current Delay Time ( S)
11.00
Over-Current Delay Time (mS)
±20
10.95
10.90
10.85
10.80
10.75
10.70
450
448
446
444
442
440
438
436
434
432
±40
±20
0
20
40
60
Temperature (ƒC)
80
100
120
±40
Threshold setting is 11 ms.
±20
0
20
40
60
80
100
Temperature (ƒC)
C013
120
C014
Threshold setting is 465 µs.
Figure 41. Overcurrent Delay Time Vs. Temperature
Figure 42. Short Circuit Charge Current Delay Time Vs.
Temperature
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
41
bq4050
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
www.ti.com
9 Power Supply Recommendations
The device manages its supply voltage dynamically according to the operation conditions. Normally, the BAT
input is the primary power source to the device. The BAT pin should be connected to the positive termination of
the battery stack. The input voltage for the BAT pin ranges from 2.2 V to 26 V.
The VCC pin is the secondary power input, which activates when the BAT voltage falls below minimum VCC. This
allows the device to source power from a charger (if present) connected to the PACK pin. The VCC pin should
be connected to the common drain of the CHG and DSG FETs. The charger input should be connected to the
PACK pin.
10 Layout
10.1 Layout Guidelines
A battery fuel gauge circuit board is a challenging environment due to the fundamental incompatibility of highcurrent traces and ultra-low current semiconductor devices. The best way to protect against unwanted trace-totrace coupling is with a component placement, such as that shown in Figure 43, where the high-current section is
on the opposite side of the board from the electronic devices. Clearly, this is not possible in many situations due
to mechanical constraints. Still, every attempt should be made to route high-current traces away from signal
traces, which enter the bq4050 gauge directly. IC references and registers can be disturbed and in rare cases
damaged due to magnetic and capacitive coupling from the high-current path.
NOTE
During surge current and ESD events, the high-current traces appear inductive and can
couple unwanted noise into sensitive nodes of the gas gauge electronics, as illustrated in
Figure 44.
BAT +
C2
C3
Q2
Low Level Circuits
Q1
F1
BAT –
C1
R1
PACK–
PACK+
J1
Copyright © 2016 , Texas Instruments Incorporated
Figure 43. Separating High- and Low-Current Sections Provides an Advantage in Noise Immunity
42
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
bq4050
www.ti.com
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
Layout Guidelines (continued)
PACK +
COMM
BMU
PACK –
Copyright © 2016 , Texas Instruments Incorporated
Figure 44. Avoid Close Spacing Between High-Current and Low-Level Signal Lines
Kelvin voltage sensing is important to accurately measure current and top and bottom cell voltages. Place all
filter components as close as possible to the device. Route the traces from the sense resistor in parallel to the
filter circuit. Adding a ground plane around the filter network can add additional noise immunity. Figure 45 and
Figure 46 demonstrate correct kelvin current sensing.
Current Direction
R SNS
Current Sensing Direction
To SRP – SRN pin or HSRP – HSRN pin
Figure 45. Sensing Resistor PCB Layout
Sense Resistor
Ground Shield
Filter Circuit
Figure 46. Sense Resistor, Ground Shield, and Filter Circuit Layout
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
43
bq4050
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
www.ti.com
Layout Guidelines (continued)
10.1.1 Protector FET Bypass and Pack Terminal Bypass Capacitors
Use wide copper traces to lower the inductance of the bypass capacitor circuit. In Figure 47, an example layout
demonstrates this technique.
C2
BAT+
C3
F1
Pack+
C3
C2
Q1
Q2
Low Level Circuits
F1
C1
BAT±
C1
J1
Pack±
Pack+
Pack±
R1
Copyright © 2016, Texas Instruments Incorporated
Figure 47. Use Wide Copper Traces to Lower the Inductance of Bypass Capacitors C1, C2, and C3
10.1.2 ESD Spark Gap
Protect the SMBus clock, data, and other communication lines from ESD with a spark gap at the connector. The
pattern in Figure 48 is recommended, with 0.2-mm spacing between the points.
Figure 48. Recommended Spark-Gap Pattern Helps Protect Communication Lines from ESD
10.2 Layout Example
THERMISTORS
CHARGE
AND
DISCHARGE
PATH
2ND LEVEL
PROTECTOR
CURRENT
FILTER
LEDS
SENSE
RESISTOR
Figure 49. Top Layer
44
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
bq4050
www.ti.com
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
Layout Example (continued)
Figure 50. Internal Layer 1
Figure 51. Internal Layer 2
CHARGE
AND
DISCHARGE
PATH
FILTER
COMPONENTS
Figure 52. Bottom Layer
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
45
bq4050
SLUSC67B – MARCH 2016 – REVISED OCTOBER 2017
www.ti.com
11 Device and Documentation Support
11.1 Documentation Support
11.1.1 Related Documentation
For related documentation, see the bq4050 Technical Reference Manual (SLUUAQ3).
11.2 Community Resources
The following links connect to TI community resources. Linked contents are provided "AS IS" by the respective
contributors. They do not constitute TI specifications and do not necessarily reflect TI's views; see TI's Terms of
Use.
TI E2E™ Online Community TI's Engineer-to-Engineer (E2E) Community. Created to foster collaboration
among engineers. At e2e.ti.com, you can ask questions, share knowledge, explore ideas and help
solve problems with fellow engineers.
Design Support TI's Design Support Quickly find helpful E2E forums along with design support tools and
contact information for technical support.
11.3 Trademarks
E2E is a trademark of Texas Instruments.
Windows is a registered trademark of Microsoft.
All other trademarks are the property of their respective owners.
11.4 Electrostatic Discharge Caution
This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with
appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.
ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more
susceptible to damage because very small parametric changes could cause the device not to meet its published specifications.
11.5 Glossary
SLYZ022 — TI Glossary.
This glossary lists and explains terms, acronyms, and definitions.
12 Mechanical, Packaging, and Orderable Information
The following pages include mechanical, packaging, and orderable information. This information is the most
current data available for the designated devices. This data is subject to change without notice and revision of
this document. For browser-based versions of this data sheet, refer to the left-hand navigation.
46
Submit Documentation Feedback
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: bq4050
PACKAGE OPTION ADDENDUM
www.ti.com
22-Sep-2017
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
Lead/Ball Finish
MSL Peak Temp
(2)
(6)
(3)
Op Temp (°C)
Device Marking
(4/5)
BQ4050RSMR
ACTIVE
VQFN
RSM
32
3000
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
BQ4050
BQ4050RSMT
ACTIVE
VQFN
RSM
32
250
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
-40 to 85
BQ4050
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of <=1000ppm threshold. Antimony trioxide based
flame retardants must also meet the <=1000ppm threshold requirement.
(3)
MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4)
There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.
(5)
Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation
of the previous line and the two combined represent the entire Device Marking for that device.
(6)
Lead/Ball Finish - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead/Ball Finish values may wrap to two lines if the finish
value exceeds the maximum column width.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
Addendum-Page 1
Samples
PACKAGE OPTION ADDENDUM
www.ti.com
22-Sep-2017
Addendum-Page 2
PACKAGE MATERIALS INFORMATION
www.ti.com
5-Jan-2019
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
Package Package Pins
Type Drawing
SPQ
Reel
Reel
A0
Diameter Width (mm)
(mm) W1 (mm)
B0
(mm)
K0
(mm)
P1
(mm)
W
Pin1
(mm) Quadrant
BQ4050RSMR
VQFN
RSM
32
3000
330.0
12.4
4.25
4.25
1.15
8.0
12.0
Q2
BQ4050RSMT
VQFN
RSM
32
250
180.0
12.4
4.25
4.25
1.15
8.0
12.0
Q2
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
5-Jan-2019
*All dimensions are nominal
Device
Package Type
Package Drawing
Pins
SPQ
Length (mm)
Width (mm)
Height (mm)
BQ4050RSMR
VQFN
RSM
32
3000
367.0
367.0
35.0
BQ4050RSMT
VQFN
RSM
32
250
210.0
185.0
35.0
Pack Materials-Page 2
GENERIC PACKAGE VIEW
RSM 32
VQFN - 1 mm max height
PLASTIC QUAD FLATPACK - NO LEAD
4 x 4, 0.4 mm pitch
This image is a representation of the package family, actual package may vary.
Refer to the product data sheet for package details.
4224982/A
www.ti.com
PACKAGE OUTLINE
RSM0032A
VQFN - 1 mm max height
SCALE 3.000
PLASTIC QUAD FLATPACK - NO LEAD
B
4.1
3.9
A
0.5
0.3
PIN 1 INDEX AREA
4.1
3.9
0.25
0.15
DETAIL
OPTIONAL TERMINAL
TYPICAL
1 MAX
C
SEATING PLANE
0.05
0.00
0.08 C
2X 2.8
1.4 0.05
4X (0.45)
(0.2) TYP
9
16
28X 0.4
8
17
EXPOSED
THERMAL PAD
2X
2.8
SEE TERMINAL
DETAIL
PIN 1 ID
(OPTIONAL)
SYMM
33
24
1
32X
32
25
SYMM
32X
0.25
0.15
0.1
0.05
C A B
0.5
0.3
4219107/A 11/2017
NOTES:
1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing
per ASME Y14.5M.
2. This drawing is subject to change without notice.
3. The package thermal pad must be soldered to the printed circuit board for thermal and mechanical performance.
www.ti.com
EXAMPLE BOARD LAYOUT
RSM0032A
VQFN - 1 mm max height
PLASTIC QUAD FLATPACK - NO LEAD
( 1.4)
SYMM
25
32
32X (0.6)
1
32X (0.2)
24
SYMM
33
(3.8)
28X (0.4)
( 0.2) VIA
17
8
(R0.05)
TYP
9
16
(3.8)
LAND PATTERN EXAMPLE
EXPOSED METAL SHOWN
SCALE:20X
0.05 MIN
ALL AROUND
0.05 MAX
ALL AROUND
SOLDER MASK
OPENING
METAL
EXPOSED METAL
EXPOSED METAL
SOLDER MASK
OPENING
METAL UNDER
SOLDER MASK
NON SOLDER MASK
DEFINED
(PREFERRED)
SOLDER MASK
DEFINED
SOLDER MASK DETAILS
4219107/A 11/2017
NOTES: (continued)
4. This package is designed to be soldered to a thermal pad on the board. For more information, see Texas Instruments literature
number SLUA271 (www.ti.com/lit/slua271).
5. Vias are optional depending on application, refer to device data sheet. If any vias are implemented, refer to their locations shown
on this view. It is recommended that vias under paste be filled, plugged or tented.
www.ti.com
EXAMPLE STENCIL DESIGN
RSM0032A
VQFN - 1 mm max height
PLASTIC QUAD FLATPACK - NO LEAD
( 1.3)
25
32
(R0.05) TYP
32X (0.6)
1
24
32X (0.2)
SYMM
33
(3.8)
28X (0.4)
METAL
TYP
17
8
16
9
SYMM
(3.8)
SOLDER PASTE EXAMPLE
BASED ON 0.1 mm THICK STENCIL
EXPOSED PAD 33:
86% PRINTED SOLDER COVERAGE BY AREA UNDER PACKAGE
SCALE:20X
4219107/A 11/2017
NOTES: (continued)
6. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate
design recommendations.
www.ti.com
IMPORTANT NOTICE AND DISCLAIMER
TI PROVIDES TECHNICAL AND RELIABILITY DATA (INCLUDING DATASHEETS), DESIGN RESOURCES (INCLUDING REFERENCE
DESIGNS), APPLICATION OR OTHER DESIGN ADVICE, WEB TOOLS, SAFETY INFORMATION, AND OTHER RESOURCES “AS IS”
AND WITH ALL FAULTS, AND DISCLAIMS ALL WARRANTIES, EXPRESS AND IMPLIED, INCLUDING WITHOUT LIMITATION ANY
IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT OF THIRD
PARTY INTELLECTUAL PROPERTY RIGHTS.
These resources are intended for skilled developers designing with TI products. You are solely responsible for (1) selecting the appropriate
TI products for your application, (2) designing, validating and testing your application, and (3) ensuring your application meets applicable
standards, and any other safety, security, or other requirements. These resources are subject to change without notice. TI grants you
permission to use these resources only for development of an application that uses the TI products described in the resource. Other
reproduction and display of these resources is prohibited. No license is granted to any other TI intellectual property right or to any third
party intellectual property right. TI disclaims responsibility for, and you will fully indemnify TI and its representatives against, any claims,
damages, costs, losses, and liabilities arising out of your use of these resources.
TI’s products are provided subject to TI’s Terms of Sale (www.ti.com/legal/termsofsale.html) or other applicable terms available either on
ti.com or provided in conjunction with such TI products. TI’s provision of these resources does not expand or otherwise alter TI’s applicable
warranties or warranty disclaimers for TI products.
Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265
Copyright © 2019, Texas Instruments Incorporated
Was this manual useful for you? yes no
Thank you for your participation!

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project

Related manuals

Download PDF

advertising