TI BQ27520YZFR-G4 System-side impedance track fuel gauge with integrated ldo Datasheet

bq27520-G4
www.ti.com
SLUSB20 – NOVEMBER 2012
System-Side Impedance Track™ Fuel Gauge With Integrated LDO
Check for Samples: bq27520-G4
FEATURES
APPLICATIONS
•
•
•
•
•
1
23
•
•
•
Single series cell Li-Ion battery fuel gauge
resides on system board
– Integrated 2.5 VDC LDO
– External low-value 10 mΩ sense resistor
Patented Impedance Track™ technology
– Adjusts for battery aging, self-discharge,
temperature, and rate changes
– Reports Remaining Capacity, State of
Charge (SOC), and Time-to-Empty
– Optional Smoothing Filter
– Battery State of Health (aging) estimation
– Supports embedded or removable packs
with up to 32Ahr capacity
– Accomodates pack swapping with
2 separate battery profiles
Microcontroller peripheral supports:
– 400-kHz I2C ™ serial interface
– 32 Bytes of Scratch-Pad FLASH NVM
– Battery Low digital ouptut warning
– Configurable SOC Interrupts
– External thermistor, internal sensor, or host
reported temperature options
Tiny 15-pin 2610 × 1956 µm, 0.5 mm pitch
NanoFree™ (CSP) package
Smartphones, Feature phones and Tablets
Digital Still and Video Cameras
Handheld Terminals
MP3 or Multimedia Players
DESCRIPTION
The Texas Instruments bq27520-G4 system-side LiIon battery fuel gauge is a microcontroller peripheral
that provides fuel gauging for single-cell Li-Ion battery
packs.
The
device
requires
little
system
microcontroller firmware development. The bq27520G4 resides on the system’s main board and manages
an embedded battery (non-removable) or a
removable battery pack.
The bq27520-G4 uses the patented Impedance
Track™ algorithm for fuel gauging, and provides
information such as remaining battery capacity
(mAh), state-of-charge (%), run-time to empty (min),
battery voltage (mV), temperature (°C) and state of
health (%).
Battery fuel gauging with the bq27520-G4 requires
only PACK+ (P+), PACK– (P–), and optional
Thermistor (T) connections to a removable battery
pack or embedded battery circuit. The device uses a
15-ball NanoFree™ (CSP) package in the nominal
dimensions of 2610 × 1956 µm with 0,5 mm lead
pitch. It is ideal for space constrained applications.
TYPICAL APPLICATION
Host System
Single Cell Li-lon
Battery Pack
VCC
CE
Power
Management
Controller
I2C
LDO
PACK+
Battery
Low
Voltage
Sense
DATA
Temp
Sense
BAT_GD
PROTECTION
IC
T
PACK-
FETs
CHG
DSG
Current
Sense
SOC_INT
1
2
3
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, NanoFree are trademarks of Texas Instruments.
is a trademark of ~NXP B.V. Corp Netherlands.
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.
Copyright © 2012, Texas Instruments Incorporated
bq27520-G4
SLUSB20 – NOVEMBER 2012
www.ti.com
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
DEVICE INFORMATION
AVAILABLE OPTIONS
PART NUMBER
bq27520YZFR-G4
bq27520YZFT-G4
(1)
(2)
FIRMWARE
VERSION (1)
PACKAGE (2)
TA
COMMUNICATION
FORMAT
3.29
(0x0329)
CSP-15
–40°C to 85°C
I2C
TAPE and REEL
QUANTITY
3000
250
Refer to the FW_VERSION subcommand to confirm the firmware version.
For the most current package and ordering information, see the Package Option Addendum at the end of this document, or see the TI
website at www.ti.com.
THERMAL INFORMATION
THERMAL METRIC (1)
bq27520-G4
YZF(15 PINS)
θJA
Junction-to-ambient thermal resistance
70
θJCtop
Junction-to-case (top) thermal resistance
17
θJB
Junction-to-board thermal resistance
20
ψJT
Junction-to-top characterization parameter
1
ψJB
Junction-to-board characterization parameter
18
θJCbot
Junction-to-case (bottom) thermal resistance
n/a
(1)
2
UNITS
°C/W
For more information about traditional and new thermal metrics, see the IC Package Thermal Metrics application report, SPRA953
Submit Documentation Feedback
Copyright © 2012, Texas Instruments Incorporated
Product Folder Links :bq27520-G4
bq27520-G4
www.ti.com
SLUSB20 – NOVEMBER 2012
PIN ASSIGNMENT AND PACKAGE DIMENSIONS
(TOP VIEW)
(BOTTOM VIEW)
B3
C3
D3
E3
E3
D3
C3
B3
A3
A2
B2
C2
D2
E2
E2
D2
C2
B2
A2
A1
B1
C1
D1
E1
E1
D1
C1
B1
A1
A3
E
xx
xx
Pin A1
Index Area
D
DIM
MIN
TYP
MAX
D
2580
2610
2640
E
1926
1956
1986
UNITS
m
Table 1. PIN FUNCTIONS
PIN
NAME
NO.
TYPE (1)
DESCRIPTION
SRP
A1
IA
Analog input pin connected to the internal coulomb counter with a Kelvin connection where SRP is nearest the
PACK– connection. Connect to 5-mΩ to 20-mΩ sense resistor.
SRN
B1
IA
Analog input pin connected to the internal coulomb counter with a Kelvin connection where SRN is nearest the Vss
connection. Connect to 5-mΩ to 20-mΩ sense resistor.
VSS
C1, C2
P
Device ground
VCC
D1
P
Regulator output and bq27520-G4 processor power. Decouple with 1μF ceramic capacitor to Vss.
REGIN
E1
P
Regulator input. Decouple with 0.1μF ceramic capacitor to Vss.
SOC_INT
A2
O
SOC state interrupts output. Generates a pulse under the conditions specified by
(1)
. Open drain output.
BAT_GD
B2
O
Battery Good push-pull indicator output. Active-low and output disabled by default. Polarity is configured via Op
Config [BATG_POL] and the output is enabled via OpConfig C [BATGSPUEN].
CE
D2
I
Chip Enable. Internal LDO is disconnected from REGIN when driven low. Note: CE has an internal ESD protection
diode connected to REGIN. Recommend maintaining VCE ≤ VREGIN under all conditions.
BAT
E2
I
Cell-voltage measurement input. ADC input. Recommend 4.8V maximum for conversion accuracy.
SCL
A3
I
Slave I2C serial communications clock input line for communication with system (Master). Open-drain I/O. Use with
10kΩ pull-up resistor (typical).
SDA
B3
I/O
Slave I2C serial communications data line for communication with system (Master). Open-drain I/O. Use with 10kΩ
pull-up resistor (typical).
BAT_LOW
C3
O
Battery Low push-pull output indicator. Active high and output enabled by default. Polarity is configured via Op
Config [BATL_POL] and the output is enabled via OpConfig C [BATLSPUEN].
TS
D3
IA
Pack thermistor voltage sense (use 103AT-type thermistor). ADC input.
BI/TOUT
E3
I/O
Battery-insertion detection input. Power pin for pack thermistor network. Thermistor-multiplexer control pin. Use with
pull-up resistor >1MΩ (1.8 MΩ typical).
(1)
I/O = Digital input/output, IA = Analog input, P = Power connection
Submit Documentation Feedback
Copyright © 2012, Texas Instruments Incorporated
Product Folder Links :bq27520-G4
3
bq27520-G4
SLUSB20 – NOVEMBER 2012
www.ti.com
ELECTRICAL SPECIFICATIONS
ABSOLUTE MAXIMUM RATINGS
over operating free-air temperature range (unless otherwise noted) (1)
PARAMETER
VREGIN
VALUE
Regulator input range
–0.3 to 6.0
VCE
CE input pin
VCC
UNIT
–0.3 to 5.5
V
(2)
V
–0.3 to VREGIN + 0.3
V
Supply voltage range
–0.3 to 2.75
V
VIOD
Open-drain I/O pins (SDA, SCL, SOC_INT )
–0.3 to 5.5
V
VBAT
BAT input pin
–0.3 to 5.5
V
–0.3 to 6.0
VI
Input voltage range to all other pins ( BI/TOUT , TS , SRP, SRN,
BAT_GD )
V
–0.3 to VCC + 0.3
Human-body model (HBM), BAT pin
ESD
(2)
V
1.5
Human-body model (HBM), all other pins
kV
2
TA
Operating free-air temperature range
–40 to 85
°C
Tstg
Storage temperature range
–65 to 150
°C
(1)
(2)
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.
Condition not to exceed 100 hours at 25 °C lifetime.
RECOMMENDED OPERATING CONDITIONS
TA = -40°C to 85°C, VREGIN = VBAT = 3.6V (unless otherwise noted)
PARAMETER
VREGIN
Supply voltage
CREGIN
External input capacitor for internal
LDO between REGIN and VSS
CLDO25
External output capacitor for internal
LDO between VCC and VSS
tPUCD
Power-up communication delay
TEST CONDITIONS
No operating restrictions
No FLASH writes
Nominal capacitor values specified.
Recommend a 5% ceramic X5R type
capacitor located close to the device.
MIN
TYP
MAX
2.8
4.5
2.45
2.8
0.47
UNIT
V
0.1
μF
1
μF
250
ms
SUPPLY CURRENT
TA = 25°C and VREGIN = VBAT = 3.6V (unless otherwise noted)
PARAMETER
ICC
(1)
ISLP+
(1)
TEST CONDITIONS
MAX
UNIT
118
μA
Sleep+ operating mode current
Fuel gauge in SLEEP+ mode.
ILOAD < Sleep Current
62
μA
23
μA
8
μA
(1)
Low-power storage-mode
current
Fuel gauge in SLEEP mode.
ILOAD < Sleep Current
IHIB
(1)
Hibernate operating-mode
current
Fuel gauge in HIBERNATE mode.
ILOAD < Hibernate Current
4
TYP
Normal operating-mode current
ISLP
(1)
MIN
Fuel gauge in NORMAL mode.
ILOAD > Sleep Current
Specified by design. Not production tested.
Submit Documentation Feedback
Copyright © 2012, Texas Instruments Incorporated
Product Folder Links :bq27520-G4
bq27520-G4
www.ti.com
SLUSB20 – NOVEMBER 2012
DIGITAL INPUT AND OUTPUT DC CHARACTERISTICS
TA = –40°C to 85°C, typical values at TA = 25°C and VREGIN = 3.6 V (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
VOL
Output voltage, low (SCL, SDA,
SOC_INT , BAT_LOW ,
BAT_GD )
IOL = 3 mA
VOH(PP)
Output voltage, high
(BAT_LOW , BAT_GD )
IOH = –1 mA
VCC –
0.5
VOH(OD)
Output voltage, high (SDA,
SCL, SOC_INT )
External pullup resistor connected to
VCC
VCC –
0.5
Input voltage, low (SDA, SCL)
VIL
Input voltage, low ( BI/TOUT )
BAT INSERT CHECK MODE active
Input voltage, high (SDA, SCL)
VIH
Input voltage, high ( BI/TOUT )
VIL(CE)
Input voltage, low (CE)
VIH(CE)
Input voltage, high (CE)
Ilkg
(1)
(1)
TYP
MAX
0.4
UNIT
V
V
–0.3
0.6
–0.3
0.6
V
1.2
BAT INSERT CHECK MODE active
VREGIN = 2.8 to 4.5V
VCC +
0.3
1.2
0.8
2.65
Input leakage current (I/O pins)
0.3
V
V
μA
Specified by design. Not production tested.
POWER-ON RESET
TA = –40°C to 85°C, typical values at TA = 25°C and VREGIN = 3.6 V (unless otherwise noted)
PARAMETER
VIT+
Positive-going battery voltage
input at VCC
VHYS
Power-on reset hysteresis
TEST CONDITIONS
MIN
TYP
MAX
UNIT
2.05
2.15
2.20
V
45
115
185
mV
UNIT
2.5V LDO REGULATOR
TA = –40°C to 85°C, CLDO25 = 1μF, VREGIN = 3.6V (unless otherwise noted)
PARAMETER
VREG25
Regulator output voltage (VCC)
MIN
NOM
MAX
2.8V ≤ VREGIN ≤ 4.5V, IOUT ≤ 16mA
TEST CONDITION
2.3
2.5
2.6
2.45V ≤ VREGIN < 2.8V (low battery),
IOUT ≤ 3mA
2.3
V
V
INTERNAL CLOCK OSCILLATORS
TA = –40°C to 85°C, 2.4 V < VCC < 2.6 V; typical values at TA = 25°C and VCC = 2.5 V (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
fOSC
High Frequency Oscillator
2.097
MHz
fLOSC
Low Frequency Oscillator
32.768
kHz
Submit Documentation Feedback
Copyright © 2012, Texas Instruments Incorporated
Product Folder Links :bq27520-G4
5
bq27520-G4
SLUSB20 – NOVEMBER 2012
www.ti.com
ADC (TEMPERATURE AND CELL MEASUREMENT) CHARACTERISTICS
TA = –40°C to 85°C, 2.4 V < VCC < 2.6 V; typical values at TA = 25°C and VCC = 2.5 V (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
VA1
Input voltage range (TS )
VSS –
0.125
2
V
VA2
Input voltage range (BAT)
VSS –
0.125
5
V
VIN(ADC)
Input voltage range
GTEMP
Internal temperature sensor
voltage gain
tADC_CONV
Conversion time
0.05
Resolution
VOS(ADC)
(1)
Effective input resistance (TS )
ZADC2
(1)
Effective input resistance (BAT)
Ilkg(ADC)
(1)
ms
15
bits
mV
8
MΩ
8
MΩ
bq27520-G4 measuring cell voltage
(1)
125
1
bq27520-G4 not measuring cell
voltage
V
mV/°C
14
Input offset
ZADC1
1
–2
100
kΩ
Input leakage current
0.3
μA
Specified by design. Not tested in production.
INTEGRATING ADC (COULOMB COUNTER) CHARACTERISTICS
TA = –40°C to 85°C, 2.4 V < VCC < 2.6 V; typical values at TA = 25°C and VCC = 2.5 V (unless otherwise noted)
PARAMETER
TEST CONDITIONS
VSR
Input voltage range, V(SRN) and
V(SRP)
VSR = V(SRN) – V(SRP)
tSR_CONV
Conversion time
Single conversion
Resolution
VOS(SR)
Input offset
INL
Integral nonlinearity error
ZIN(SR)
Ilkg(SR)
(1)
6
(1)
(1)
MIN
TYP
–0.125
MAX
UNIT
0.125
V
1
14
s
15
±0.007
Effective input resistance
±0.034
2.5
Input leakage current
bits
μV
10
% FSR
MΩ
0.3
μA
Specified by design. Not tested in production.
Submit Documentation Feedback
Copyright © 2012, Texas Instruments Incorporated
Product Folder Links :bq27520-G4
bq27520-G4
www.ti.com
SLUSB20 – NOVEMBER 2012
DATA FLASH MEMORY CHARACTERISTICS
TA = –40°C to 85°C, 2.4 V < VCC < 2.6 V; typical values at TA = 25°C and VCC = 2.5 V (unless otherwise noted)
PARAMETER
tDR
(1)
TEST CONDITIONS
Data retention
Flash-programming write
cycles (1)
tWORDPROG
(1)
ICCPROG
(1)
tDFERASE
tIFERASE
(1)
tPGERASE
(1)
(1)
(1)
MIN
TYP
MAX
UNIT
10
Years
20,000
Cycles
Word programming time
Flash-write supply current
5
2
ms
10
mA
Data flash master erase time
200
ms
Instruction flash master erase
time
200
ms
20
ms
Flash page erase time
Specified by design. Not production tested
I2C-COMPATIBLE INTERFACE COMMUNICATION TIMING CHARACTERISTICS
TA = –40°C to 85°C, 2.4 V < VCC < 2.6 V; typical values at TA = 25°C and VCC = 2.5 V (unless otherwise noted)
MAX
UNIT
tr
SCL/SDA rise time
PARAMETER
300
ns
tf
SCL/SDA fall time
300
ns
tw(H)
SCL pulse duration (high)
600
ns
tw(L)
SCL pulse duration (low)
1.3
μs
tsu(STA)
Setup for repeated start
600
ns
td(STA)
Start to first falling edge of SCL
600
ns
tsu(DAT)
Data setup time
100
ns
th(DAT)
Data hold time
0
ns
tsu(STOP)
Setup time for stop
600
ns
t(BUF)
Bus free time between stop and
start
66
μs
fSCL
Clock frequency
(1)
TEST CONDITIONS
MIN
(1)
TYP
400
kHz
If the clock frequency (fSCL) is > 100 kHz, use 1-byte write commands for proper operation. All other transactions types are supported at
400 kHz. (Refer to I2C INTERFACE and I2C Command Waiting Time)
Figure 1. I2C-Compatible Interface Timing Diagrams
Submit Documentation Feedback
Copyright © 2012, Texas Instruments Incorporated
Product Folder Links :bq27520-G4
7
bq27520-G4
SLUSB20 – NOVEMBER 2012
www.ti.com
GENERAL DESCRIPTION
The bq27520-G4 accurately predicts the battery capacity and other operational characteristics of a single Libased rechargeable cell. It can be interrogated by a system processor to provide cell information, such as timeto-empty (TTE) and state-of-charge (SOC) as well as SOC interrupt signal to the host.
Information is accessed through a series of commands, called Standard Commands. Further capabilities are
provided by the additional Extended Commands set. Both sets of commands, indicated by the general format
Command( ), are used to read and write information contained within the device control and status registers, as
well as its data flash locations. Commands are sent from system to gauge using the bq27520-G4 ’s I2C serial
communications engine, and can be executed during application development, system manufacture, or endequipment operation.
Cell information is stored in the device in non-volatile flash memory. Many of these data flash locations are
accessible during application development. They cannot, generally, be accessed directly during end-equipment
operation. Access to these locations is achieved by either use of the bq27520-G4 ’s companion evaluation
software, through individual commands, or through a sequence of data-flash-access commands. To access a
desired data flash location, the correct data flash subclass and offset must be known.
The key to the bq27520-G4 ’s high-accuracy gas gauging prediction is Texas Instrument’s proprietary Impedance
Track™ algorithm. This algorithm uses cell measurements, characteristics, and properties to create state-ofcharge predictions that can achieve less than 1% error across a wide variety of operating conditions and over the
lifetime of the battery.
The device measures charge/discharge activity by monitoring the voltage across a small-value series sense
resistor (5 mΩ to 20 mΩ typ.) located between the system’s Vss and the battery’s PACK- terminal. When a cell is
attached to the device, cell impedance is learned, based on cell current, cell open-circuit voltage (OCV), and cell
voltage under loading conditions.
The device external temperature sensing is optimized with the use of a high accuracy negative temperature
coefficient (NTC) thermistor with R25 = 10.0kΩ ±1%. B25/85 = 3435K ± 1% (such as Semitec NTC 103AT).
Alternatively, the bq27520-G4 can also be configured to use its internal temperature sensor or receive
temperature data from the host processor. When an external thermistor is used, a 18.2k pull up resistor between
BI/TOUT and TS pins is also required. The bq27520-G4 uses temperature to monitor the battery-pack
environment, which is used for fuel gauging and cell protection functionality.
To minimize power consumption, the device has different power modes: NORMAL, SLEEP+, SLEEP,
HIBERNATE, and BAT INSERT CHECK. The bq27520-G4 passes automatically between these modes,
depending upon the occurrence of specific events, though a system processor can initiate some of these modes
directly.
For complete operational details, refer to bq27520-G4 Technical Reference Manual.
NOTE
FORMATTING CONVENTIONS IN THIS DOCUMENT:
Commands: italics with parentheses and no breaking spaces, e.g. RemainingCapacity( ).
NVM Data: italics, bold, and breaking spaces, e.g. Design Capacity.
Register bits and flags: brackets and italics, e.g. [TDA]
NVM Data bits: brackets, italics and bold, e.g: [LED1]
Modes and states: ALL CAPITALS, e.g. UNSEALED mode.
8
Submit Documentation Feedback
Copyright © 2012, Texas Instruments Incorporated
Product Folder Links :bq27520-G4
bq27520-G4
www.ti.com
SLUSB20 – NOVEMBER 2012
DATA COMMANDS
STANDARD DATA COMMANDS
Thebq27520-G4 uses a series of 2-byte standard commands to enable system reading and writing of battery
information. Each standard command has an associated command-code pair, as indicated in Table 2. Because
each command consists of two bytes of data, two consecutive I2C transmissions must be executed both to
initiate the command function, and to read or write the corresponding two bytes of data. Additional details are
found in the bq27520-G4 Technical Reference Manual.
Table 2. Standard Commands
NAME
Control( )
CNTL
AtRate( )
AtRateTimeToEmpty( )
Temperature( )
Voltage( )
COMMAND CODE
UNITS
SEALED
ACCESS
0x00 / 0x01
N/A
R/W
0x02 / 0x03
mA
R/W
0x04 / 0x05
Minutes
R
TEMP
0x06 / 0x07
0.1 K
R/W
VOLT
0x08 / 0x09
mV
R
FLAGS
0x0a / 0x0b
N/A
R
NominalAvailableCapacity( )
NAC
0x0c / 0x0d
mAh
R
FullAvailableCapacity( )
FAC
0x0e / 0x0f
mAh
R
RemainingCapacity( )
RM
0x10 / 0x11
mAh
R
FullChargeCapacity( )
FCC
0x12 / 0x13
mAh
R
0x14 / 0x15
mA
R
0x16 / 0x17
Minutes
R
Flags( )
AverageCurrent( )
TimeToEmpty( )
TTE
StandbyCurrent( )
0x18 / 0x19
mA
R
StandbyTimeToEmpty( )
0x1a / 0x1b
Minutes
R
0x1c / 0x1d
% / num
R
0x1e / 0x1f
num
R
StateOfHealth( )
SOH
CycleCount( )
StateOfCharge( )
0x20 / 0x21
%
R
InstantaneousCurrent( )
SOC
0x22 / 0x23
mA
R
InternalTemperature( )
0x28 / 0x29
0.1 K
R
ResistanceScale( )
OperationConfiguration( )
DesignCapacity( )
0x2a / 0x2b
Op Config
R
0x2c / 0x2d
N/A
R
0x2e / 0x2f
mAh
R
Submit Documentation Feedback
Copyright © 2012, Texas Instruments Incorporated
Product Folder Links :bq27520-G4
9
bq27520-G4
SLUSB20 – NOVEMBER 2012
www.ti.com
Control( ): 0x00/0x01
Issuing a Control( ) command requires a subsequent 2-byte subcommand. These additional bytes specify the
particular control function desired. The Control( ) command allows the system to control specific features of the
bq27520-G4 during normal operation and additional features when the device is in different access modes, as
described in Table 3. Additional details are found in the bq27520-G4 Technical Reference Manual.
Table 3. Control( ) Subcommands
CNTL
DATA
SEALED
ACCESS
CONTROL_STATUS
0x0000
Yes
Reports the status of DF checksum, hibernate, IT, etc.
DEVICE_TYPE
0x0001
Yes
Reports the device type (eg: 0x0520)
FW_VERSION
0x0002
Yes
Reports the firmware version on the device type
PREV_MACWRITE
0x0007
Yes
Returns previous Control( ) subcommand code
CHEM_ID
0x0008
Yes
Reports the chemical identifier of the Impedance Track™ configuration
OCV_CMD
0x000c
Yes
Request the gauge to take a OCV measurement
BAT_INSERT
0x000d
Yes
Forces Flags( ) [BAT_DET] bit set when OpConfig B [BIE] = 0
BAT_REMOVE
0x000e
Yes
Forces Flags( ) [BAT_DET] bit clear when OpConfig B [BIE] = 0
SET_HIBERNATE
0x0011
Yes
Forces CONTROL_STATUS [HIBERNATE] to 1
CLEAR_HIBERNATE
0x0012
Yes
Forces CONTROL_STATUS [HIBERNATE] to 0
SET_SLEEP+
0x0013
Yes
Forces CONTROL_STATUS [SNOOZE] to 1
CLEAR_SLEEP+
0x0014
Yes
Forces CONTROL_STATUS [SNOOZE] to 0
DF_VERSION
0x001F
Yes
Returns the Data Flash Version code
SEALED
0x0020
No
Places the bq27520-G4 in SEALED access mode
IT_ENABLE
0x0021
No
Enables the Impedance Track™ (IT) algorithm
RESET
0x0041
No
Forces a full reset of the bq27520-G4
CNTL FUNCTION
10
DESCRIPTION
Submit Documentation Feedback
Copyright © 2012, Texas Instruments Incorporated
Product Folder Links :bq27520-G4
bq27520-G4
www.ti.com
SLUSB20 – NOVEMBER 2012
FUNCTIONAL DESCRIPTION
The bq27520-G4 measures the voltage, temperature, and current to determine battery capacity and state of
charge (SOC) based on the patented Impedance Track™ algorithm (Refer to Application Report SLUA450,
Theory and Implementation of Impedance Track Battery Fuel-Gauging Algorithm for more information). The
bq27520-G4 monitors charge and discharge activity by sensing the voltage across a small-value resistor (5 mΩ
to 20 mΩ typ.) between the SRP and SRN pins and in series with the battery. By integrating charge passing
through the battery, the battery’s SOC is adjusted during battery charge or discharge.
Battery capacity is found by comparing states of charge before and after applying the load with the amount of
charge passed. When a system load is applied, the impedance of the battery is measured by comparing the
open circuit voltage (OCV) obtained from a predefined function for present SOC with the measured voltage under
load. Measurements of OCV and charge integration determine chemical state of charge and chemical capacity
(Qmax). The initial Qmax values are taken from a cell manufacturers' data sheet multiplied by the number of
parallel cells. It is also used for the value in Design Capacity. The bq27520-G4 acquires and updates the
battery-impedance profile during normal battery usage. It uses this profile, along with SOC and the Qmax value,
to determine FullChargeCapacity( ) and StateOfCharge( ), specifically for the present load and temperature.
FullChargeCapacity( ) is reported as capacity available from a fully charged battery under the present load and
temperature until Voltage( ) reaches the Terminate Voltage. NominalAvailableCapacity( ) and
FullAvailableCapacity( ) are the uncompensated (no or light load) versions of RemainingCapacity( ) and
FullChargeCapacity( ) respectively.
The bq27520-G4 has two Flags( ) bits and two pins to warn the host if the battery’s SOC has fallen to critical
levels. If RemainingCapacity( ) falls below the first capacity threshold specified by SOC1 Set Threshold, the
Flags ( ) [SOC1] bit is set and is cleared if RemainingCapacity( ) rises above the SOC1 Clear Threshold. If
enabled via OpConfig C [BATLSPUEN], the BAT_LOW pin reflects the status of the [SOC1] flag bit. Also, if
enabled by OpConfig B [BL_INT], the SOC_INT will toggle upon a state change of the [SOC1] flag bit.
As Voltage( ) falls below the SysDown Set Volt Threshold, the Flags( ) [SYSDOWN] bit is set and SOC_INT
will toggle once to provide a final warning to shut down the system. As Voltage( ) rises above SysDown Clear
Voltage the [SYSDOWN] bit is cleared and SOC_INT will toggle once to signal the status change.
Additional details are found in the bq27520-G4 Technical Reference Manual.
Submit Documentation Feedback
Copyright © 2012, Texas Instruments Incorporated
Product Folder Links :bq27520-G4
11
bq27520-G4
SLUSB20 – NOVEMBER 2012
www.ti.com
COMMUNICATIONS
I2C INTERFACE
The bq27520-G4 supports the standard I2C read, incremental read, quick read, one byte write, and incremental
write functions. The 7 bit device address (ADDR) is the most significant 7 bits of the hex address and is fixed as
1010101. The first 8-bits of the I2C protocol will; therefore, be 0xAA or 0xAB for write or read, respectively.
Host generated
S
ADDR[6:0]
0 A
Gauge generated
CMD [7:0]
A
DATA [7:0]
A P
S
ADDR[6:0]
(a) 1-byte write
S
ADDR[6:0]
0 A
1 A
DATA [7:0]
N P
(b) quick read
CMD [7:0]
A Sr
ADDR[6:0]
1 A
DATA [7:0]
N P
(c) 1- byte read
S
ADDR[6:0]
0 A
CMD [7:0]
A Sr
ADDR[6:0]
1 A
DATA [7:0]
A ...
DATA [7:0]
N P
(d) incremental read
S
ADDR[6:0]
0 A
CMD[7:0]
A
DATA [7:0]
A
DATA [7:0]
A
...
A P
(e) incremental write
(S = Start , Sr = Repeated Start , A = Acknowledge , N = No Acknowledge , and P = Stop).
The “quick read” returns data at the address indicated by the address pointer. The address pointer, a register
internal to the I2C communication engine, will increment whenever data is acknowledged by the bq27520-G4 or
the I2C master. “Quick writes” function in the same manner and are a convenient means of sending multiple
bytes to consecutive command locations (such as two-byte commands that require two bytes of data)
The following command sequences are not supported:
Attempt to write a read-only address (NACK after data sent by master):
Attempt to read an address above 0x6B (NACK command):
I2C Time Out
The I2C engine will release both SDA and SCL if the I2C bus is held low for 2 seconds. If the bq27520-G4 was
holding the lines, releasing them will free them for the master to drive the lines. If an external condition is holding
either of the lines low, the I2C engine will enter the low power sleep mode.
12
Submit Documentation Feedback
Copyright © 2012, Texas Instruments Incorporated
Product Folder Links :bq27520-G4
bq27520-G4
www.ti.com
SLUSB20 – NOVEMBER 2012
I2C Command Waiting Time
To ensure proper operation at 400 kHz, a t(BUF) ≥ 66 μs bus free waiting time should be inserted between all
packets addressed to the bq27520-G4 . In addition, if the SCL clock frequency (fSCL) is > 100 kHz, use individual
1-byte write commands for proper data flow control. The following diagram shows the standard waiting time
required between issuing the control subcommand the reading the status result. An OCV_CMD subcommand
requires 1.2 seconds prior to reading the result. For read-write standard command, a minimum of 2 seconds is
required to get the result updated. For read-only standard commands, there is no waiting time required, but the
host should not issue all standard commands more than two times per second. Otherwise, the gauge could result
in a reset issue due to the expiration of the watchdog timer.
S
ADDR [6:0]
0 A
CMD [7:0]
A
DATA [7:0]
A P
66ms
S
ADDR [6:0]
0 A
CMD [7:0]
A
DATA [7:0]
A P
66ms
S
ADDR [6:0]
0 A
CMD [7:0]
A Sr
ADDR [6:0]
1 A
DATA [7:0]
A
DATA [7:0]
N P
66ms
N P
66ms
Waiting time inserted between two 1-byte write packets for a subcommand and reading results
(required for 100 kHz < fSCL £ 400 kHz)
S
ADDR [6:0]
0 A
CMD [7:0]
A
DATA [7:0]
S
ADDR [6:0]
0 A
CMD [7:0]
A Sr
ADDR [6:0]
A
1 A
DATA [7:0]
A P
DATA [7:0]
A
66ms
DATA [7:0]
Waiting time inserted between incremental 2-byte write packet for a subcommand and reading results
(acceptable for fSCL £ 100 kHz)
S
ADDR [6:0]
DATA [7:0]
0 A
A
CMD [7:0]
DATA [7:0]
A Sr
ADDR [6:0]
N P
1 A
DATA [7:0]
A
DATA [7:0]
A
66ms
Waiting time inserted after incremental read
I2C Clock Stretching
A clock stretch can occur during all modes of fuel gauge operation. In SLEEP and HIBERNATE modes, a short
clock stretch will occur on all I2C traffic as the device must wake-up to process the packet. In the other modes (
BAT INSERT CHECK , NORMAL, SLEEP+ ) clock stretching will only occur for packets addressed for the fuel
gauge. The majority of clock stretch periods are small as the I2C interface performs normal data flow control.
However, less frequent yet more significant clock stretch periods may occur as blocks of Data Flash are updated.
The following table summarizes the approximate clock stretch duration for various fuel gauge operating
conditions.
Approximate
Duration
Gauging Mode
Operating Condition / Comment
SLEEP
HIBERNATE
Clock stretch occurs at the beginning of all traffic as the device wakes up.
≤ 4 ms
BAT INSERT
CHECK
NORMAL
SLEEP+
Clock stretch occurs within the packet for flow control. (after a start bit, ACK or first data bit)
≤ 4 ms
Normal Ra table Data Flash updates.
24 ms
Data Flash block writes.
72 ms
Restored Data Flash block write after loss of power.
116 ms
End of discharge Ra table Data Flash update.
144 ms
Submit Documentation Feedback
Copyright © 2012, Texas Instruments Incorporated
Product Folder Links :bq27520-G4
13
bq27520-G4
SLUSB20 – NOVEMBER 2012
www.ti.com
REFERENCE SCHEMATICS
U1
BQ27520
SCHEMATIC
14
Submit Documentation Feedback
Copyright © 2012, Texas Instruments Incorporated
Product Folder Links :bq27520-G4
PACKAGE OPTION ADDENDUM
www.ti.com
29-May-2013
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
Lead/Ball Finish
(2)
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
(4/5)
BQ27520YZFR-G4
ACTIVE
DSBGA
YZF
15
3000
Green (RoHS
& no Sb/Br)
SNAGCU
Level-1-260C-UNLIM
-40 to 85
BQ27520
BQ27520YZFT-G4
ACTIVE
DSBGA
YZF
15
250
Green (RoHS
& no Sb/Br)
SNAGCU
Level-1-260C-UNLIM
-40 to 85
BQ27520
(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)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability
information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that
lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between
the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight
in homogeneous material)
(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.
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 MATERIALS INFORMATION
www.ti.com
12-Jul-2013
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
Package Package Pins
Type Drawing
SPQ
Reel
Reel
A0
Diameter Width (mm)
(mm) W1 (mm)
BQ27520YZFR-G4
DSBGA
YZF
15
3000
180.0
8.4
BQ27520YZFT-G4
DSBGA
YZF
15
250
180.0
8.4
Pack Materials-Page 1
B0
(mm)
K0
(mm)
P1
(mm)
W
Pin1
(mm) Quadrant
2.1
2.76
0.81
4.0
8.0
Q1
2.1
2.76
0.81
4.0
8.0
Q1
PACKAGE MATERIALS INFORMATION
www.ti.com
12-Jul-2013
*All dimensions are nominal
Device
Package Type
Package Drawing
Pins
SPQ
Length (mm)
Width (mm)
Height (mm)
BQ27520YZFR-G4
DSBGA
YZF
15
3000
210.0
185.0
35.0
BQ27520YZFT-G4
DSBGA
YZF
15
250
210.0
185.0
35.0
Pack Materials-Page 2
D: Max = 2.64 mm, Min = 2.58 mm
E: Max = 1.986 mm, Min =1.926 mm
IMPORTANT NOTICE
Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, enhancements, improvements and other
changes to its semiconductor products and services per JESD46, latest issue, and to discontinue any product or service per JESD48, latest
issue. Buyers should obtain the latest relevant information before placing orders and should verify that such information is current and
complete. All semiconductor products (also referred to herein as “components”) are sold subject to TI’s terms and conditions of sale
supplied at the time of order acknowledgment.
TI warrants performance of its components to the specifications applicable at the time of sale, in accordance with the warranty in TI’s terms
and conditions of sale of semiconductor products. Testing and other quality control techniques are used to the extent TI deems necessary
to support this warranty. Except where mandated by applicable law, testing of all parameters of each component is not necessarily
performed.
TI assumes no liability for applications assistance or the design of Buyers’ products. Buyers are responsible for their products and
applications using TI components. To minimize the risks associated with Buyers’ products and applications, Buyers should provide
adequate design and operating safeguards.
TI does not warrant or represent that any license, either express or implied, is granted under any patent right, copyright, mask work right, or
other intellectual property right relating to any combination, machine, or process in which TI components or services are used. Information
published by TI regarding third-party products or services does not constitute a license to use such products or services or a warranty or
endorsement thereof. Use of such information may require a license from a third party under the patents or other intellectual property of the
third party, or a license from TI under the patents or other intellectual property of TI.
Reproduction of significant portions of TI information in TI data books or data sheets is permissible only if reproduction is without alteration
and is accompanied by all associated warranties, conditions, limitations, and notices. TI is not responsible or liable for such altered
documentation. Information of third parties may be subject to additional restrictions.
Resale of TI components or services with statements different from or beyond the parameters stated by TI for that component or service
voids all express and any implied warranties for the associated TI component or service and is an unfair and deceptive business practice.
TI is not responsible or liable for any such statements.
Buyer acknowledges and agrees that it is solely responsible for compliance with all legal, regulatory and safety-related requirements
concerning its products, and any use of TI components in its applications, notwithstanding any applications-related information or support
that may be provided by TI. Buyer represents and agrees that it has all the necessary expertise to create and implement safeguards which
anticipate dangerous consequences of failures, monitor failures and their consequences, lessen the likelihood of failures that might cause
harm and take appropriate remedial actions. Buyer will fully indemnify TI and its representatives against any damages arising out of the use
of any TI components in safety-critical applications.
In some cases, TI components may be promoted specifically to facilitate safety-related applications. With such components, TI’s goal is to
help enable customers to design and create their own end-product solutions that meet applicable functional safety standards and
requirements. Nonetheless, such components are subject to these terms.
No TI components are authorized for use in FDA Class III (or similar life-critical medical equipment) unless authorized officers of the parties
have executed a special agreement specifically governing such use.
Only those TI components which TI has specifically designated as military grade or “enhanced plastic” are designed and intended for use in
military/aerospace applications or environments. Buyer acknowledges and agrees that any military or aerospace use of TI components
which have not been so designated is solely at the Buyer's risk, and that Buyer is solely responsible for compliance with all legal and
regulatory requirements in connection with such use.
TI has specifically designated certain components as meeting ISO/TS16949 requirements, mainly for automotive use. In any case of use of
non-designated products, TI will not be responsible for any failure to meet ISO/TS16949.
Products
Applications
Audio
www.ti.com/audio
Automotive and Transportation
www.ti.com/automotive
Amplifiers
amplifier.ti.com
Communications and Telecom
www.ti.com/communications
Data Converters
dataconverter.ti.com
Computers and Peripherals
www.ti.com/computers
DLP® Products
www.dlp.com
Consumer Electronics
www.ti.com/consumer-apps
DSP
dsp.ti.com
Energy and Lighting
www.ti.com/energy
Clocks and Timers
www.ti.com/clocks
Industrial
www.ti.com/industrial
Interface
interface.ti.com
Medical
www.ti.com/medical
Logic
logic.ti.com
Security
www.ti.com/security
Power Mgmt
power.ti.com
Space, Avionics and Defense
www.ti.com/space-avionics-defense
Microcontrollers
microcontroller.ti.com
Video and Imaging
www.ti.com/video
RFID
www.ti-rfid.com
OMAP Applications Processors
www.ti.com/omap
TI E2E Community
e2e.ti.com
Wireless Connectivity
www.ti.com/wirelessconnectivity
Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265
Copyright © 2013, Texas Instruments Incorporated