Texas Instruments System-Side Impedance Track bq27500 User manual

www.ti.com
1 INTRODUCTION
1.1 FEATURES 1.2 APPLICATIONS
1.3 DESCRIPTION
Host System
Single Cell Li-Ion
Battery Pack
PACK-
PROTECTION
IC
CHG
DSG
Temp
Sense
Battery
Good
Current
Sense
I2C T
LDO
PACK+
Voltage
Sense
Battery
Low
Warning
FETs
bq27500/1
RID
RID
Sense*
* bq27501 Only
Power
Management
Controller
bq27500
bq27501System-Side Impedance Track™ Fuel Gauge
SLUS785 – SEPTEMBER 2007
•Battery Fuel Gauge for 1-Series Li-Ion
•SmartphonesApplications
•PDAs•Resides on System Main Board
•Digital Still and Video Cameras– Works with Embedded or Removable
•Handheld TerminalsBattery Packs
•MP3 or Multimedia Players•Two Varieties
– bq27500: Uses PACK+,PACK-, and TBattery Terminals– bq27501: Includes Battery Pack ID Resistor(RID) Terminal
The Texas Instruments bq27500/01 System-SideLi-Ion Battery Fuel Gauge is a micro-controller•Micro-Controller Peripheral Provides:
peripheral that provides fuel gauging for single cell– Accurate Battery Fuel Gauging
Li-Ion battery packs. The device requires little system– Internal Temperature Sensor for System
micro-controller firmware development. TheTemperature Reporting
bq27500/01 resides on the system’s main board, and–Battery Low Interrupt Warning
manages an embedded battery (non-removable) or a–Battery Insertion Indicator
removable battery pack.– Battery ID Detection– 96 bytes of Non-Volatile Scratch Pad
The bq27500/01 uses the patented ImpedanceFLASH
Track™ algorithm for fuel gauging, and providesinformation such as remaining battery capacity•Battery Fuel Gauge Based on Patented
(mAh), state-of-charge (%), run-time to empty (min.),Impedance Track™ Technology
battery voltage (mV), and temperature ( °C).– Models the Battery Discharge Curve forAccurate Time-to-Empty Predictions
Battery fuel gauging with the bq27500 requires only– Automatically Adjusts for Battery Aging,
PACK+ (P+), PACK- (P-), and Thermistor (T)Battery Self Discharge, and
connections to a removable battery pack orTemperature/Rate Inefficiencies
embedded battery circuit. The bq27501 works with– Low Value Sense Resistor (10m Ωor Less)
identification resistors in battery packs, to gauge•I
2
C™ Interface for Connection to System
batteries of different fundamental chemistries and/orMicro-Controller Port
significantly different rated capacities.•12-Pin 2,5 mm ×4,0 mm SON Package
TYPICAL APPLICATION
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of TexasInstruments semiconductor products and disclaimers thereto appears at the end of this document.Impedance Track is a trademark of Texas Instruments.I
2
C is a trademark of Philips Electronics.
UNLESS OTHERWISE NOTED this document contains
Copyright © 2007, Texas Instruments IncorporatedPRODUCTION DATA information current as of publication date.Products conform to specifications per the terms of TexasInstruments standard warranty. Production processing does notnecessarily include testing of all parameters.

www.ti.com
Contents
bq27500
bq27501
System-Side Impedance Track™ Fuel Gauge
SLUS785 – SEPTEMBER 2007
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed inconductive foam during storage or handling to prevent electrostatic damage to the MOS gates.
1 INTRODUCTION .......................................... 14.2 DATA FLASH INTERFACE ......................... 161.1 FEATURES ........................................... 14.3 MANUFACTURER INFORMATION BLOCKS ...... 171.2 APPLICATIONS ...................................... 14.4 ACCESS MODES ................................... 171.3 DESCRIPTION ....................................... 14.5 SEALING/UNSEALING DATA FLASH .............. 172 DEVICE INFORMATION ................................. 34.6 DATA FLASH SUMMARY ........................... 182.1 AVAILABLE OPTIONS ............................... 35 FUNCTIONAL DESCRIPTION ........................ 202.2 PIN DIAGRAMS ...................................... 35.1 FUEL GAUGING .................................... 202.3 TERMINAL FUNCTIONS ............................. 35.2 IMPEDANCE TRACK™ VARIABLES ............... 213 ELECTRICAL SPECIFICATIONS ...................... 45.3 DETAILED DESCRIPTION OF DEDICATED PINS .233.1 ABSOLUTE MAXIMUM RATINGS ................... 45.4 TEMPERATURE MEASUREMENT ................. 263.2 RECOMMENDED OPERATING CONDITIONS ...... 45.5 OVERTEMPERATURE INDICATION ............... 265.6 CHARGING AND CHARGE-TERMINATION3.3 POWER-ON RESET .................................. 4
INDICATION ......................................... 263.4 INTERNAL TEMPERATURE SENSORCHARACTERISTICS ................................. 55.7 POWER MODES .................................... 273.5 HIGH FREQUENCY OSCILLATOR .................. 55.8 POWER CONTROL ................................. 293.6 LOW FREQUENCY OSCILLATOR ................... 55.9 AUTOCALIBRATION ................................ 303.7 INTEGRATING ADC (COULOMB COUNTER)
6 APPLICATION-SPECIFIC INFORMATION .......... 31CHARACTERISTICS ................................. 5
6.1 BATTERY PROFILE STORAGE AND SELECTION 313.8 ADC (TEMPERATURE AND CELL
6.2 APPLICATION-SPECIFIC FLOW AND CONTROL .31MEASUREMENT) CHARACTERISTICS ............. 5
7 COMMUNICATIONS .................................... 333.9 DATA FLASH MEMORY CHARACTERISTICS ...... 6
7.1 I
2
C INTERFACE ..................................... 333.10 I
2
C-COMPATIBLE INTERFACE COMMUNICATION
8 REFERENCE SCHEMATICS .......................... 34TIMING CHARACTERISTICS ........................ 6
8.1 SCHEMATIC ........................................ 344 GENERAL DESCRIPTION .............................. 84.1 DATA COMMANDS .................................. 9
2Contents Submit Documentation Feedback

www.ti.com
2 DEVICE INFORMATION
2.1 AVAILABLE OPTIONS
2.2 PIN DIAGRAMS
BAT
VSS
SRN
SRP
VCC
BAT_GD
SDA
SCL
1
2
3
4
5
6
12
11
10
9
8
7
BAT_LOW_
TS
1
2
3
4
5
6
12
11
10
9
8
7
BI/TOUT
BAT
VSS
VCC
BAT_LOW_
TS
BI/TOUT
NC
SRN
SRP
BAT_GD
SDA
SCL
RID
bq27500 bq27501
2.3 TERMINAL FUNCTIONS
bq27500
bq27501System-Side Impedance Track™ Fuel Gauge
SLUS785 – SEPTEMBER 2007
COMMUNICATION TAPE and REELPART NUMBER PACKAGE
(1)
T
A
FORMAT QUANTITY
bq27500DRZR 3000bq27500DRZT 30012-pin, 2,5 mm x 4,0 mm
–40 °C to 85 °C I
2
CSONbq27501DRZR
(2)
3000bq27501DRZT
(2)
300
(1) For the most current package and ordering information, see the Package Option Addendum at the end of this document, or see the TIwebsite at www.ti.com .(2) Product Preview
TERMINAL
I/O
(1)
DESCRIPTIONNAME NAMEPIN NO.
bq27500 bq27501
Battery Low output indicator. Active high by default, though polarity can be configured1 BAT_LOW BAT_LOW O
through the [BATL_POL] in Operation Configuration Push-pull output.Battery-insertion detection input. Power pin for pack thermistor network. Thermistor2 BI/TOUT BI/TOUT I/O
multiplexer control pin. Open-drain I/O. use with pull-up resistor > 1M Ω(1.8M Ωtypical)3 TS TS P Pack thermistor voltage sense (use 103AT-type thermistor). ADC input.4 BAT BAT I Cell-voltage measurement input. ADC input.5 V
CC
V
CC
P Processor power input. Decouple with 0.1 μF capacitor, minimum.6 V
SS
V
SS
P Device ground.Analog input pin connected to the internal coulomb-counter where SRP is nearest the7 SRP SRP IA
CELL- connection. Connect to 5-20m Ωsense resistor.Analog input pin connected to the internal coulomb-counter where SRN is nearest the8 SRN SRN IA
PACK- connection. Connect to 5-20m Ωsense resistor.No connection (bq27500). Resistor ID input (bq27501). Analog input with current sourcing9 NC RID –, I
capabilities.
Slave I
2
C serial communications data line for communication with system ( Master).10 SDA SDA I/O
Open-drain I/O. Use with 10k Ωpull-up resistor (typical).Slave I
2
C serial communications clock input line for communication with system ( Master).11 SCL SCL I
Open-drain I/O. Use with 10k Ωpull-up resistor (typical).Battery Good indicator. Active low by default, though polarity can be configured through12 BAT_GD BAT_GD O
the [BATG_POL] of Operation Configuration. Open-drain output.
(1) I/O = Digital Input/Output, IA = Analog Input, P = Power Connection
Submit Documentation Feedback DEVICE INFORMATION 3

www.ti.com
3 ELECTRICAL SPECIFICATIONS
3.1 ABSOLUTE MAXIMUM RATINGS
3.2 RECOMMENDED OPERATING CONDITIONS
3.3 POWER-ON RESET
bq27500
bq27501
System-Side Impedance Track™ Fuel Gauge
SLUS785 – SEPTEMBER 2007
over operating free-air temperature range (unless otherwise noted)
(1)
PARAMETER VALUE UNIT
V
CC
Supply voltage range –0.3 to 2.75 VV
IOD
Open-drain I/O pins (BI_TOUT, SDA, SDL, BAT_GD) –0.3 to 6 VV
BAT
BAT input pin –0.3 to +6V
I
Input voltage range to all other pins (TS, SRP, SRN, RID [bq27501 only], NC –0.3 to V
CC
+ 0.3 V[bq27500 only])
1 kVESD Human Body Model (HMB)
2 kVT
F
Functional temperature range –40 to 100 °CT
STG
Storage temperature range –65 to 150 °C
(1) Stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. These are stress ratingsonly, and functional operation of the device at these or any other conditions beyond those indicated under recommended operatingconditions is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
T
A
= 25 °C, V
CC
= 2.5 V (unless otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
V
CC
Supply Voltage 2.4 2.5 2.6 VI
CC
Normal operating mode current
(1)
95 μAI
SLP
Low-power storage mode current
(2)
15 μAI
CC
Hibernate operating mode current
(3)
2μAV
OL
Output voltage low (SDA, BAT_LOW, BI/TOUT) I
OL
= 0.5 mA 0.4 VV
OH(PP)
Output high voltage (BAT_LOW) I
OH
= –1 mA V
CC
–0.5 VExternal pull-up resistorV
OH(OD)
Output high voltage (SDA, SCL, BI/TOUT) V
CC
–0.5 Vconnected to V
CC
V
IL
Input voltage low (SDA, SCL) –0.3 0.8
VV
IH(OD)
Input voltage high (SDA, SCL, BI/TOUT) 2 6C
IN
Input capacitance 5 pFV
A1
Input voltage range (TS, RID [bq27501 only]) V
SS
–0.125 2 VV
A2
Input voltage range (BAT) V
SS
–0.125 5 VV
A3
Input voltage range (SRP, SRN) V
SS
–0.125 0.125 Vt
PUCD
Power up communication delay 250 msT
A
Operating free-air temperature range –40 85 °C
(1) High level of system activity.(2) Low level of system activity.(3) Fuel gauge algorithm power inactive. Only able to receive I
2
C communication.
T
A
= –40 °C to 85 °C, Typical Values at T
A
= 25 °C and V
BAT
= 3.6 V (unless otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
V
IT+
Positive-going battery voltage input at V
CC
2.09 2.20 2.31 VV
HYS
45 115 185 mV
ELECTRICAL SPECIFICATIONS4Submit Documentation Feedback

www.ti.com
3.4 INTERNAL TEMPERATURE SENSOR CHARACTERISTICS
3.5 HIGH FREQUENCY OSCILLATOR
3.6 LOW FREQUENCY OSCILLATOR
3.7 INTEGRATING ADC (COULOMB COUNTER) CHARACTERISTICS
3.8 ADC (TEMPERATURE AND CELL MEASUREMENT) CHARACTERISTICS
bq27500
bq27501System-Side Impedance Track™ Fuel Gauge
SLUS785 – SEPTEMBER 2007
T
A
= –40 °C to 85 °C, 2.4 V < V
CC
< 2.6 V; Typical Values at T
A
= 25 °C and V
CC
= 2.5 V (unless otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
G
TEMP
Temperature sensor voltage gain –2.0 mV/ °C
T
A
= –40 °C to 85 °C, 2.4 V < V
CC
< 2.6 V; Typical Values at T
A
= 25 °C and V
CC
= 2.5 V (unless otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
f
OSC
Operating frequency 2.097 MHzT
A
= 0 °C to 60 °C –2.0% 0.38% 2.0%f
EIO
Frequency error
(1) (2)
T
A
= –20 °C to 70 °C –3.0% 0.38% 3.0%T
A
= –40 °C to 85 °C –4.5% 0.38% 4.5%t
SXO
Start-up time
(3)
2.5 5 ms
(1) The frequency error is measured from 2.097 MHz.(2) The frequency drift is included and measured from the trimmed frequency at V
CC
= 2.5V, T
A
= 25 °C.(3) The startup time is defined as the time it takes for the oscillator output frequency to be ±3%.
T
A
= –40 °C to 85 °C, 2.4 V < V
CC
< 2.6 V; Typical Values at T
A
= 25 °C and V
CC
= 2.5 V (unless otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
f
LOSC
Operating frequency 32.768 kHzT
A
= 0 °C to 60 °C –1.5% 0.25% 1.5%f
LEIO
Frequency error
(1) (2)
T
A
= –20 °C to 70 °C –2.5% 0.25% 2.5%T
A
= –40 °C to 85 °C –4.0% 0.25% 4.0%t
LSXO
Start-up time
(3)
500 μs
(1) The frequency drift is included and measured from the trimmed frequency at V
CC
= 2.5V, T
A
= 25 °C.(2) The frequency error is measured from 32.768 kHz.(3) The startup time is defined as the time it takes for the oscillator output frequency to be ±3%.
T
A
= –40 °C to 85 °C, 2.4 V < V
CC
< 2.6 V; Typical Values at T
A
= 25 °C and V
CC
= 2.5 V (unless otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
V
SR_IN
Input voltage range, V
(SRN)
and V
(SRP)
V
SR
= V
(SRN)
– V
(SRP)
–0.125 0.125 Vt
SR_CONV
Conversion time Single conversion 1 sResolution 14 15 bitsBefore calibration 1 mVV
SR_OS
Input offset
After calibration 10 μVINL Integral nonlinearity error ±0.007 ±0.034 % FSRZ
SR_IN
Effective input resistance
(1)
2.5 M ΩI
SR_LKG
Input leakage current
(1)
0.3 μA
(1) Specified by design. Not tested in production.
T
A
= –40 °C to 85 °C, 2.4 V < V
CC
< 2.6 V; Typical Values at T
A
= 25 °C and V
CC
= 2.5 V (unless otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
V
ADC_IN
Input voltage range –0.2 1 V
Submit Documentation Feedback ELECTRICAL SPECIFICATIONS 5

www.ti.com
3.9 DATA FLASH MEMORY CHARACTERISTICS
3.10 I
2
C-COMPATIBLE INTERFACE COMMUNICATION TIMING CHARACTERISTICS
bq27500
bq27501
System-Side Impedance Track™ Fuel Gauge
SLUS785 – SEPTEMBER 2007
ADC (TEMPERATURE AND CELL MEASUREMENT) CHARACTERISTICS (continued)
T
A
= –40 °C to 85 °C, 2.4 V < V
CC
< 2.6 V; Typical Values at T
A
= 25 °C and V
CC
= 2.5 V (unless otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
t
ADC_CONV
Conversion time 125 msResolution 14 15 bitsV
ADC_OS
Input offset 1 mVZ
ADC1
Effective input resistance (TS, RID 8 M Ω[bq27501 only])
bq27500/1 not measuring cell voltage 8 M ΩZ
ADC2
Effective input resistance (BAT)
(1)
bq27500/1 measuging cell voltage 100 k ΩI
ADC_LKG
Input Leakage Current
(1)
0.3 μA
(1) Specified by design. Not tested in production.
T
A
= –40 °C to 85 °C, 2.4 V < V
CC
< 2.6 V; Typical Values at T
A
= 25 °C and V
CC
= 2.5 V (unless otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
t
ON
Data retention See
(1)
10
(1)
YearsFlash programming write-cycles See
(1)
20,000 Cyclest
WORDPROG
Word programming time See
(1)
2 msI
CCPROG
Flash-write supply current 5 10 mA
(1) Specified by design. Not production tested
T
A
= –40 °C to 85 °C, 2.4 V < V
CC
< 2.6 V; Typical Values at T
A
= 25 °C and V
CC
= 2.5 V (unless otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
t
r
SCL/SDA rise time 1 μst
f
SCL/SDA fall time 300 nst
w(H)
SCL pulse width (high) 4 μst
w(L)
SCL pulse width (low) 4.7 μst
su(STA)
Setup for repeated start 4.7 μst
d(STA)
Start to first falling edge of SCL 4 μst
su(DAT)
Data setup time 250 nsReceive mode 0t
h(DAT)
Data hold time nsTransmit mode 300t
su(STOP)
Setup time for stop 4 μst
BUF
Bus free time between stop and start 4.7 μsf
SCL
Clock frequency 10 100 kHzt
BUSERR
Bus error timeout 17.3 21.2 s
ELECTRICAL SPECIFICATIONS6Submit Documentation Feedback

www.ti.com
bq27500
bq27501System-Side Impedance Track™ Fuel Gauge
SLUS785 – SEPTEMBER 2007
Figure 3-1. I
2
C-Compatible Interface Timing Diagrams
Submit Documentation Feedback ELECTRICAL SPECIFICATIONS 7

www.ti.com
4 GENERAL DESCRIPTION
bq27500
bq27501
System-Side Impedance Track™ Fuel Gauge
SLUS785 – SEPTEMBER 2007
The bq27500/1 accurately predicts the battery capacity and other operational characteristics of a singleLi-based rechargeable cell. It can be interrogated by a system processor to provide cell information, suchas State-of-Charge (SOC), Time-to-Empty (TTE) and Time-to-Full (TTF).
Information is accessed through a series of commands, called Standard Commands. Further capabilitiesare provided by the additional Extended Commands set. Both sets of commands, indicated by the generalformat Command( ), are used to read and write information contained within the bq27500/1 control andstatus registers, as well as its data flash locations. Commands are sent from system to gauge using thebq27500/1’s I
2
C serial communications engine, and can be executed during application development,pack manufacture, or end-equipment operation.
Cell information is stored in the bq27500/1 in non-volatile flash memory. Many of these data flashlocations are accessible during application development. They cannot be accessed directly duringend-equipment operation. Access to these locations is achieved by either use of the bq27500/1'scompanion evaluation software, through individual commands, or through a sequence of data-flash-accesscommands. To access a desired data flash location, the correct data flash subclass and offset must beknown.
The bq27500/1 provides 96 bytes of user-programmable data flash memory, partitioned into 3 32-byteblocks: Manufacturer Info Block A,Manufacturer Info Block B, and Manufacturer Info Block C. Thisdata space is accessed through a data flash interface. For specifics on accessing the data flash, seeSection 4.3 Manufacturer Information Blocks.
The key to the bq27500/1’s high-accuracy gas gauging prediction is Texas Instrument’s proprietaryImpedance Track™ algorithm. This algorithm uses cell measurements, characteristics, and properties tocreate state-of-charge predictions that can achieve less than 1% error across a wide variety of operatingconditions and over the lifetime of the battery.
The bq27500/1 measures charge/discharge activity by monitoring the voltage across a small-value seriessense resistor (5 m Ωto 20 m Ωtyp.) located between the system's Vss and the battery’s PACK– terminal.When a cell is attached to the bq27500/1, cell impedance is computed, based on cell current, cell OpenCircuit Voltage (OCV), and cell voltage under loading conditions.
The bq27500/1 can use an NTC thermistor (default is Semitec 103AT) for temperature measurement, orcan also be configured to use its internal temperature sensor. The bq27500/1 uses temperature to monitorthe battery-pack environment, which is used for fuel gauging and cell protection functionality.
To minimize power consumption, the bq27500/1 has several power modes: NORMAL, SLEEP,HIBERNATE, and BAT INSERT CHECK. The bq27500/1 passes automatically between these modes,depending upon the occurrence of specific events, though a system processor can initiate some of thesemodes directly. More details can be found in the Section 5.7 POWER MODES.
NOTE
FORMATTING CONVENTIONS IN THIS DOCUMENT:
Commands: italics with parentheses and no breaking spaces, e.g. RemainingCapacity( ).
Data Flash: italics,bold, and breaking spaces, e.g. Design Capacity
Register Bits and Flags: brackets only, e.g. [TDA]
Data Flash Bits: italics and bold, e.g: [LED1]
Modes and states: ALL CAPITALS, e.g. UNSEALED mode.
8GENERAL DESCRIPTION Submit Documentation Feedback

www.ti.com
4.1 DATA COMMANDS
4.1.1 STANDARD DATA COMMANDS
bq27500
bq27501System-Side Impedance Track™ Fuel Gauge
SLUS785 – SEPTEMBER 2007
The bq27500/1 uses a series of 2-byte standard commands to enable system reading and writing ofbattery information. Each standard command has an associated command-code pair, as indicated inTable 4-1 . Because each command consists of two bytes of data, two consecutive I
2
C transmissions mustbe executed both to initiate the command function, and to read or write the corresponding two bytes ofdata. Additional options for transferring data, such as spooling, are described in Section 7.1 I
2
CINTERFACE. Standard commands are accessible in NORMAL operation. Read/Write permissions dependon the active access mode, SEALED or UNSEALED (for details on the SEALED and UNSEALED states,see Section 4.4 Access Modes).
Table 4-1. Standard Commands
COMMAND SEALED UNSEALEDNAME UNITSCODE ACCESS ACCESS
Control( ) CNTL 0x00 / 0x01 N/A R/W R/WAtRate( ) AR 0x02 / 0x03 mA R/W R/WAtRateTimeToEmpty( ) ARTTE 0x04 / 0x05 Minutes R RTemperature( ) TEMP 0x06 / 0x07 0.1 °K R RVoltage( ) VOLT 0x08 / 0x09 mV R RFlags( ) FLAGS 0x0a / 0x0b N/A R RNominalAvailableCapacity( ) NAC 0x0c / 0x0d mAh R RFullAvailableCapacity( ) FAC 0x0e / 0x0f mAh R RRemainingCapacity( ) RM 0x10 / 0x11 mAh R RFullChargeCapacity( ) FCC 0x12 / 0x13 mAh R RAverageCurrent( ) AI 0x14 / 0x15 mA R RTimeToEmpty( ) TTE 0x16 / 0x17 Minutes R RTimeToFull( ) TTF 0x18 / 0x19 Minutes R RStandbyCurrent( ) SI 0x1a / 0x1b mA R RStandbyTimeToEmpty( ) STTE 0x1c / 0x1d Minutes R RMaxLoadCurrent( ) MLI 0x1e / 0x1f mA R RMaxLoadTimeToEmpty( ) MLTTE 0x20 / 0x21 Minutes R RAvailableEnergy( ) AE 0x22 / 0x23 10mWhr R RAveragePower( ) AP 0x24 / 0x25 10mW R RTimeToEmptyAtConstantPower( ) TTECP 0x26 / 0x27 Minutes R RReserved RSVD 0x28 / 0x29 N/A R RCycleCount( ) CC 0x2a / 0x2b Counts R RStateOfCharge( ) SOC 0x2c / 0x2d % R R
Submit Documentation Feedback GENERAL DESCRIPTION 9

www.ti.com
bq27500
bq27501
System-Side Impedance Track™ Fuel Gauge
SLUS785 – SEPTEMBER 2007
4.1.1.1 Control( ): 0x00/0x01
Issuing a Control( ) command requires a subsequent two-byte sub-command. These additional bytesspecify the particular control function desired. The Control( ) command allows the system to controlspecific features of the bq27500 during normal operation and additional features when the bq27500/1 is indifferent access modes, as described in Table 4-2 .
Table 4-2. Control( ) Subcommands
CNTL SEALEDCNTL FUNCTION DESCRIPTIONDATA ACCESS
CONTROL STATUS 0x0000 Yes Reports the status of DF Checksum, Hibernate, IT, etc.DEVICE TYPE 0x0001 Yes Reports the device type (eg: "bq27500")FW VERSION 0x0002 Yes Reports the firmware version on the device typeHW VERSION 0x0003 Yes Reports the hardware version of the device typeReserved 0x0004 No Not to be usedRESET DATA 0x0005 No Returns reset dataReserved 0x0006 No Not to be usedPREV_MACWRITE 0x0007 No Returns previous MAC command codeReports the chemical identifier of the Impedance Track™CHEMID 0x0008 Yes
configurationBOARD OFFSET 0x0009 No Forces the device Board Offset to be measured and storedCC INT OFFSET 0x000b No Forces the device to measure and store the internal CC offsetSET HIBERNATE 0x0011 Yes Forces DF:Pack Configuration [HIBERNATE] to 1CLEAR HIBERNATE 0x0012 Yes Forces DF:Pack Configuration [HIBERNATE] to 0SEALED 0x0020 No Places the bq27500/1 in SEALED access modeIT ENABLE 0x0021 No Enables the Impedance Track™ algorithmIFCHECKSUM 0x0022 No Reports the instruction flash checksumCALMODE 0x0040 No Places the bq27500/1 in calibration modeRESET 0x0041 No Forces a full reset of the bq27500/1
4.1.1.1.1 CONTROL STATUS: 0X0000
Instructs the gas gauge to return status information to Control addresses 0x00/0x01. The status wordincludes the following information.
Table 4-3. CONTROL STATUS Bit Definitions
Flags( ) bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0
High Byte – FAS SS - CCA BCA – –Low Byte – HIBERNATE – SLEEP LDMD RUP_DIS VOK QEN
FAS = Status bit indicating the bq27500/1 is in FULL ACCESS SEALED state. Active when set.SS = Status bit indicating the bq27500/1 is in SEALED State. Active when set.CCA = Status bit indicating the bq27500/1 is Coulomb Counter Calibration routine is active. Active when set.BCA = Status bit indicating the bq27500/1 Board Calibration routine is active. Active when set.HIBERNATE = Status bit indicating a request for entry into HIBERNATE from SLEEP mode. True when set. Default is 0.SLEEP = Status bit indicating the bq27500/1 is in SLEEP mode. True when set. Default is 0.LDMD = Status bit indicating the bq27500/1 Impedance Track™ algorithm is using constant-power mode. True when set. Default is 0(constant-current mode)RUP_DIS = Status bit indicating the bq27500/1 Ra table updates are disabled. Updates disabled when set.VOK = Status bit indicating the bq27500/1 voltages are OK for QMAX. True when set.QEN = Status bit indicating the bq27500/1 QMAX updates enabled. True when set.
4.1.1.1.2 DEVICE TYPE: 0x0001
Instructs the fuel gauge to return the device type to addresses 0x00/0x01.
GENERAL DESCRIPTION10 Submit Documentation Feedback