How it Works
Texas Instruments
Loading...
bq20z90D
Datasheet
25 pgs533.33 Kb0
Table of contents
Loading...

Texas Instruments bq20z90D Datasheet

www.ti.com
SLUS662A – DECEMBER 2005 – REVISED JUNE 2006
SBS 1.1-COMPLIANT GAS GAUGE ENABLED WITH IMPEDANCE TRACK™
bq20z90

FEATURES

• Patented Impedance Track™ Technology
• Optional Pulse Charging Feature for
Improved Charge Times
Accurately Measures Available Charge in • Drives 3-, 4- or 5-Segment LED Display for Li-Ion and Li-Polymer Batteries Remaining Capacity Indication
• Better than 1% Error Over Lifetime of the • Supports SHA-1 Authentication
Battery
• Instant Accuracy – No Learning Cycle
• Lifetime Data Logging
• 30-Pin TSSOP (DBT)
Required
• Automatically adjusts for battery aging,
battery self discharge and temperature inefficiencies
• Supports the Smart Battery Specification

APPLICATIONS

• Notebook PCs
• Medical and Test Equipment
• Portable Instrumentation
SBS V1.1
• Works With the TI bq29330 Analog Front-End
(AFE) Protection IC to Provide Complete Pack Electronics Solution

DESCRIPTION

The bq20z90 SBS-compliant gas gauge IC, incorporating patented Impedance Track™
• Full Array of Programmable Voltage, Current, technology, is designed for battery-pack or in-system
and Temperature Protection Features
• Integrated Time Base Removes Need for
External Crystal with Optional Crystal Input
• Electronics for 7.2-V, 10.8-V or 14.4-V Battery
Packs With 50% Fewer External Components
• Based on a Powerful Low-Power RISC CPU
Core With High-Performance Peripherals
• Integrated Field Programmable FLASH
Memory Eliminates the Need for External Configuration Memory
• Measures Charge Flow Using a
High-Resolution, 16-Bit Integrating Delta-Sigma Converter
– Better Than 0.65 nVh of Resolution – Self-Calibrating
• Uses 16-Bit Delta-Sigma Converter for
Accurate Voltage and Temperature Measurements
• Extensive Data Reporting Options For
Improved System Interaction
installation. The bq20z90 measures and maintains an accurate record of available charge in Li-ion or Li-polymer batteries using its integrated high-performance analog peripherals. The bq20z90 monitors capacity change, battery impedance, open-circuit voltage, and other critical parameters of the battery pack, and reports the information to the system host controller over a serial-communication bus. It is designed to work with the bq29330 analog front-end (AFE) protection IC to maximize functionality and safety, and minimize component count and cost in smart battery circuits.
The Impedance Track technology continuously analyzes the battery impedance, resulting in superior gas-gauging accuracy. This enables remaining capacity to be calculated with discharge rate, temperature, and cell aging all accounted for during each stage of every cycle.
AVAILABLE OPTIONS
PACKAGE
T
A
–40 ° C to
85 ° C
30-PIN TSSOP (DBT) 30-PIN TSSOP (DBT)
Tube Tape & Reel
bq20z90DBT
(1)
bq20z90DBTR
(2)
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
IMPEDANCE TRACK is a trademark of Texas Instruments.
PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of the Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters.
(1) A single tube quantity is 50 units. (2) A single reel quantity is 2000 units
Copyright © 2005–2006, Texas Instruments Incorporated
www.ti.com
LDO+
Reset
I2C
SMBus
HDQ
Pack+
Pack-
Discharge/Charge/
Pre-ChargeFETs
2-TierOverCurrent
Protection
2kBytesof DataFlash
Fuse
Watchdog&
Protection Timing
Cell Balancin g Drive
SystemInterface SystemInterface
32.768kHz
16DigGPIO&Peripherals
8DigGPIOor AnalogGPI
2.5V/3.3V(LED)
NchFET Drive
(ChargePumps)
RAMConfiguration,Status
andControlRegisters
24kx22Program
Flash
2kBytes
ofRAM
6kx22
MaskROM
Cell, Ba t and Pack
Voltage Tran slation
Precharge
Control
Host Inte rface & Data
Mana gement
TOUT andLEDOUT
PowerSupport
Reset
AnalogOutputDrive
32kHzOscillatorand8MHzSystemClock
T1
StandardDelta-Sigma A toDConverter
IntegratingDelta-Sigma A toDConverter
1 2
7
6
5
4
3
30
29 28
27 26
25
24
NC
XALERT
SDATA
SCLK
CLKOUT
TS1
VCELL-
VCELL+
NC
RBI
VCC
VSS
MRST
TS2
PRES
SRN
PFIN
SAFE
SMBD
NC
LED4
LED5
*VSS
SRP
8
9
10
11 12
23
22 21
20
19
13 14 15
18 17 16
SMBC
DISP
NC
LED3
LED2 LED1
NC-Nointernalconnection
bq20z90
SLUS662A – DECEMBER 2005 – REVISED JUNE 2006

SYSTEM PARTITIONING DIAGRAM

2
TSSOP (DBT)
(TOP VIEW)
Submit Documentation Feedback
www.ti.com
SLUS662A – DECEMBER 2005 – REVISED JUNE 2006
TERMINAL FUNCTIONS
TERMINAL
NO. NAME
1 NC – Not used— leave floating 2 XALERT I Input from bq29330 XALERT output. 3 SDATA I/O Data transfer to and from bq29330 4 SCLK I/O Communication clock to the bq29330 5 CLKOUT O 32.768-kHz output for the bq29330. This pin should be directly connected to the AFE. 6 TS1 I 1stThermistor voltage input connection to monitor temperature 7 TS2 I 2ndThermistor voltage input connection to monitor temperature 8 PRES I Active low input to sense system insertion and typically requires additional ESD protection
9 PFIN I
10 SAFE O Active high output to enforce additional level of safety protection; e.g., fuse blow. 11 SMBD I/OD SMBus data open-drain bidirectional pin used to transfer address and data to and from the bq20z90 12 NC – Not used— leave floating 13 SMBC I/OD SMBus clock open-drain bidirectional pin used to clock the data transfer to and from the bq20z90
14 DISP I 15 NC – Not used— leave floating
16 LED1 O LED1 display segment that drives an external LED depending on the firmware configuration 17 LED2 O LED2 display segment that drives an external LED depending on the firmware configuration 18 LED3 O LED3 display segment that drives an external LED depending on the firmware configuration 19 LED4 O LED4 display segment that drives an external LED depending on the firmware configuration 20 LED5 O LED5 display segment that drives an external LED depending on the firmware configuration 21 VSS – Connected I/O pin to VSS
22 SRP IA
23 SRN IA
24 MRST I 25 VSS P Negative Supply Voltage
26 VCC P Positive Supply Voltage 27 RBI P 28 NC – Not used— leave floating
29 VCELL+ I Input from bq29330 used to read a scaled value of individual cell voltages 30 VCELL- I Input from bq29330 used to read a scaled value of individual cell voltages
(1) I = Input, IA = Analog input, I/O = Input/output, I/OD = Input/Open-drain output, O = Output, OA = Analog output, P = Power
(1)
I/O
Active low input to detect secondary protector output status and allows the bq20z90 to report the status of the 2ndlevel protection output
Display control for the LEDs. This pin is typically connected to bq29330 REG via a 100-k Ω resistor and a push-button switch to VSS.
Connections to the top of a small-value sense resistor to monitor the battery charge- and discharge-current flow
Connections to the bottom of a small-value sense resistor to monitor the battery charge- and discharge-current flow
Master reset input that forces the device into reset when held low. Must be held high for normal operation
Backup power to the bq20z90 data registers during periods of low operating voltage. RBI accepts a storage capacitor or a battery input.
DESCRIPTION
bq20z90
Submit Documentation Feedback
3
www.ti.com
bq20z90
SLUS662A – DECEMBER 2005 – REVISED JUNE 2006

ABSOLUTE MAXIMUM RATINGS

over operating free-air temperature range (unless otherwise noted)
V
relative to V
CC
V
relative to V
(IOD)
VIrelative to V T
A
T
stg
SS
SS
SS
Supply voltage range –0.3 V to 2.75 V Open-drain I/O pins –0.3 V to 6 V Input voltage range to all other pins –0.3 V to V Operating free-air temperature range –40 ° C to 85 ° C Storage temperature range –65 ° C to 150 ° C
(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.

ELECTRICAL CHARACTERISTICS

V
= 2.4 V to 2.6 V, TA= –40 ° C to 85 ° C (unless otherwise noted)
CC
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
V
Supply voltage 2.4 2.5 2.6 V
CC
I
Operating mode current µ A
CC
I
Low-power storage mode current µ A
(SLP)
Output voltage low SMBC, SMBD, SDATA, SCLK, SAFE IOL= 0.5 mA 0.4 V
V
OL
LED1 – LED5 IOL= 10 mA 0.4 V
V
Output high voltage, SMBC, SMBD, SDATA, SCLK, SAFE IOH= –1 mA VCC– 0.5 V
OH
V
Input voltage low SMBC, SMBD, SDATA, SCLK, XALERT, –0.3 0.8
IL
PRES, PFIN DISP –0.3 0.8 V
V
Input voltage high SMBC, SMBD, SDATA, SCLK, XALERT, 2 6
IH
PRES, PFIN DISP 2 V
C
Input capacitance 5 pF
IN
V
Input voltage range VCELL+, VCELL-,TS1, TS2 - 0.2 0.8XV
(AI1)
V
Input voltage range SR1, SR2 – 0.20 0.20
(AI2)
Z
Input impedance VCELL+, VCELL-, TS1, TS2 0 V–1 V 8 M Ω
(AI2)
Z
Input impedance SR1, SR2 0 V–1 V 2.5 M Ω
(AI1)
(1) This value does not include the bq29330
(1)
No flash programming 400 bq20z90 + bq29330 475 Sleep mode 8 bq20z90 + bq29330 51
RANGE
(1)
(1)
CC
+ 0.3 V
CC
+ 0.3 V
CC
V
V
V
4
Submit Documentation Feedback
www.ti.com

POWER-ON RESET

1.76
1.77
1.78
1.79
1.8
1.81
-40 -20 0 20 40 60 80
T -Free-AirTemperature-°C
A
Power-OnResetNegative-GoingV
oltage-V
POWERONRESETBEHAVIOR
FREE-AIRTEMPERATURE
VS
V
= 2.4V to 2.6 V, TA= –40 ° C to 85 ° C (unless otherwise noted)
CC
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
V V
Negative-going voltage input 1.7 1.8 1.9 V
IT–
Power-on reset hysteresis 50 125 200 mV
HYS
bq20z90
SLUS662A – DECEMBER 2005 – REVISED JUNE 2006

INTEGRATING ADC (Coulomb Counter) CHARACTERISTICS

V
= 2.4V to 2.6 V, TA= –40 ° C to 85 ° C (unless otherwise noted)
CC
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
V
(SR)
V
(SROS)
Input voltage range, V Input offset 10 µ V
INL Integral nonlinearity error 0.007% 0.034%

OSCILLATOR

V
= 2.4 V to 2.6 V, TA= –40 ° C to 85 ° C (unless otherwise noted)
CC
HIGH FREQUENCY OSCILLATOR
f
Operating Frequency 4.194 MHz
(OSC)
f
Frequency Error
(EIO)
t
Start-up Time
(SXO)
LOW FREQUENCY OSCILLATOR
f
(LOSC)
f
(LEIO)
(1) The frequency error is measured from 4.194 MHz. (2) The frequency drift is included and measured from the trimmed frequency at V (3) The start-up time is defined as the time it takes for the oscillator output frequency to be within 1% of the specified frequency. (4) The frequency error is measured from 32.768 kHz.
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
(1) (2)
(3)
Operating Frequency 32.768 KHz
Frequency Error
(2) (4)
and V
(SRN)
(SRP)
V
= V(SRN) – V(SRP) –0.2 0.2 V
(SR)
-3% 0.25% 3%
TA= 20 ° C to 70 ° C -2% 0.25% 2%
2.5 5 ms
-2.5% 0.25% 2.5%
TA= 20 ° C to 70 ° C -1.5% 0.25% 1.5%
= 2.5 V, TA= 25 ° C.
CC
Submit Documentation Feedback
5
www.ti.com
bq20z90
SLUS662A – DECEMBER 2005 – REVISED JUNE 2006
OSCILLATOR (continued)
V
= 2.4 V to 2.6 V, TA= –40 ° C to 85 ° C (unless otherwise noted)
CC
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
t
Start-up time
(LSXO)
(5) The start-up time is defined as the time it takes for the oscillator output frequency to be ± 3%.

DATA FLASH MEMORY CHARACTERISTICS

V
= 2.4 V to 2.6 V, TA= –40 ° C to 85 ° C (unless otherwise noted)
CC
t
DR
t
(WORDPROG)
I
(DDdPROG)
(1) Assured by design. Not production tested

REGISTER BACKUP

V
= 2.4 V to 2.6 V, TA= –40 ° C to 85 ° C (unless otherwise noted)
CC
I
V
(1) Specified by design. Not production tested.
RB data-retention input current V
(RB)
RB data-retention voltage
(RB)
(5)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
Data retention See Flash programming write-cycles See Word programming time See Flash-write supply current See
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
(1)
(RB)
V
(RB)
to 50 ° C
(1) (1) (1) (1)
> V > V
, V
(RBMIN) (RBMIN)
CC
, V
CC
20,000 Cycles
< V
IT-
< V
, TA= 0 ° C 40 160
IT-
500 µ s
10 Years
2 ms
5 10 mA
1500 nA
1.7 V
6
Submit Documentation Feedback
www.ti.com

SMBus TIMING SPECIFICATIONS

V
= 2.4 V to 2.6 V, TA= –40 ° C to 85 ° C (unless otherwise noted)
CC
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
f
SMB
f
MAS
t
BUF
t
HD:STA
t
SU:STA
t
SU:STO
t
HD:DAT
t
SU:DAT
t
TIMEOUT
t
LOW
t
HIGH
t
LOW:SEXT
t
LOW:MEXT
t
F
t
R
(1) The bq20z90 times out when any clock low exceeds t (2) t (3) t (4) t
SMBus operating frequency Slave mode, SMBC 50% duty cycle 10 100 SMBus master clock frequency Master mode, no clock low slave extend 51.2 Bus free time between start and stop 4.7 Hold time after (repeated) start 4 Repeated start setup time 4.7 Stop setup time 4
Data hold time
Data setup time 250 Error signal/detect See Clock low period 4.7 Clock high period See Cumulative clock low slave extend time See Cumulative clock low master extend time See Clock/data fall time (V Clock/data rise time 0.9 VCC to (VILMAX – 0.15 V) 1000
. is minimum bus idle time. SMBC = 1 for t > 50 µ s causes reset of any transaction involving the bq20z90 that is in progress.
HIGH:MAX LOW:SEXT LOW:MEXT
is the cumulative time a slave device is allowed to extend the clock cycles in one message from initial start to the stop.
is the cumulative time a master device is allowed to extend the clock cycles in one message from initial start to the stop.
SLUS662A – DECEMBER 2005 – REVISED JUNE 2006
Receive mode 0 Transmit mode 300 ns
(1)
(2) (3) (4)
– 0.15 V) to (V
ILMAX
.
TIMEOUT
+ 0.15 V) 300
IHMIN
25 35 ms
4 50
bq20z90
kHz
µ s
µ s
25
ms
10
ns
SMBus TIMING DIAGRAM
Submit Documentation Feedback
7
www.ti.com
bq20z90
SLUS662A – DECEMBER 2005 – REVISED JUNE 2006

FEATURE SET

Primary (1st Level) Safety Features

The bq20z90 supports a wide range of battery and system protection features that can easily be configured. The primary safety features include:
• Battery cell over/under voltage protection
• Battery pack over/under voltage protection
• 2 independent charge overcurrent protection
• 3 independent discharge overcurrent protection
• Short circuit protection
• Over temperature protection
• AFE Watchdog
• Host Watchdog

Secondary (2nd Level) Safety Features

The secondary safety features of the bq20z90 can be used to indicate more serious faults via the SAFE (pin 10) pin. This pin can be used to blow an in-line fuse to permanently disable the battery pack from charging or discharging. The secondary safety features include:
• Safety over voltage
• Battery cell imbalance
• 2nd level protection IC input
• Safety over current
• Safety over temperature
• Open thermistor
• Charge FET and Zero-Volt Charge FET fault
• Discharge FET fault
• Fuse blow failure detection
• AFE Communication error
• AFE Verification error
• Internal flash data error

Charge Control Features

The bq20z90 charge control features include:
• Report 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.
• Determine the chemical state of charge of each battery cell using Impedance Track™. Using cell balancing algorithm, gradually decrease the differences in the cells' state of charge in a fully charged state. This prevents high cells from overcharging, causing excessive degradation and also increases the usable pack energy by preventing early charge termination.
• Support Pre-charging/Zero-volt charging
• Support Fast charging
• Support Pulse charging
• Support Charge Inhibit and Charge Suspend modes
• Report charging faults and also indicate charging status via charge and discharge alarms.

Gas Gauging

The bq20z90 uses the Impedance Track™ Technology to measure and calculate the available charge in battery cells. The achievable accuracy is better than 1% error over the lifetime of the battery and there is no full charge-discharge learning cycle required.
8
Submit Documentation Feedback
Loading...
+ 17 hidden pages
Buy Points How it Works FAQ Contact Us Questions and Suggestions Privacy Policy Cookie Policy Terms of Use