PW
bq29312
www.ti.com
SLUS546E – MARCH 2003 – REVISED MARCH 2005
THREE AND FOUR CELL LITHIUM-ION OR
LITHIUM-POLYMER BATTERY PROTECTION AFE
FEATURES
APPLICATIONS
•
•
•
•
•
•
•
•
•
•
•
•
•
•
2-, 3-, or 4-Cell Series Protection Control
Can Directly Interface With the bq2084 Gas
Gauges
Provides Individual Cell Voltages and Battery
Voltage to Battery Management Host
Integrated Cell Balancing Drive
I2C Compatible User Interface Allows Access
to Battery Information
Programmable Threshold and Delay for Over
Load and Short Circuit During Charge and
Discharge
System Alert Interrupt Output
Host Control Can Initiate Sleep Power Mode
and Ship Mode
Integrated 3.3-V, 25-mA LDO
Supply Voltage Range From 4.5 V to 25 V
Low Supply Current of 60-µA Typical
Notebook PCs
Medical and Test Equipment
Portable Instrumentation
DESCRIPTION
The bq29312 is a 2-, 3-, or 4-cell lithium-ion battery
pack protection analog front end (AFE) IC that
incorporates a 3.3-V, 25-mA low-dropout regulator
(LDO). The bq29312 also integrates an I2C compatible interface to extract battery parameters such as
cell voltages and control output status. Other parameters such as current protection thresholds and
delays can be programmed into the bq29312 to
increase the flexibility of the battery management
system.
The bq29312 provides safety protection for overcharge, overload, short-circuit, overvoltage, and
undervoltage conditions in conjunction with the battery management host. In overload and short-circuit
conditions, the bq29312 turns the FET drive off
autonomously dependant on the internal configuration
setting.
SYSTEM PARTITIONING DIAGRAM
Discharge / Charge /
Pre-Charge FETs
Fuse
Pack +
bq29312
PF Input
PCH FET Drive
Power Management
LDO, TOUT and Power mode control
Temperature Measurement
<1% Error
768 Bytes of
User Flash
SMBus
TINT
32kHz Clock
Generator
Supply Voltage
T1
Pre-Charge
FET Drive
Cell Balancing
Drive
LDO, Therm Output Drive & UVLO
System Watchdog
Delay Counters
System Interface
RAM Registers
32kHz
Cell Balancing Algorithm and Control
SBS v1.1 Data
System Interface
bq29312 RAM/Comms Validation
1st Level OC
Protection
1st Level OV and
UV Protection
Pack Under Voltage
Power Mode
Control
Cell and Pack
Voltage
Measurement
I2 C
XAlert
Sleep
Power Mode Control
2nd Level Over Voltage Protection
bq2084
Pre-charge Control Fail-Safe Protection
2-Tier Over Current Protection
Capacity Prediction <1% Error
Voltage Level Translator
Pack Sense Resistor
(10 - 30 mΩ)
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.
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 © 2003–2005, Texas Instruments Incorporated
bq29312
www.ti.com
SLUS546E – MARCH 2003 – REVISED MARCH 2005
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.
DESCRIPTION (Continued)
The communications interface allows the host to observe and control the current status of the bq29312. It
enables cell balancing, enters different power modes, sets overload levels, sets the overload blanking delay time,
sets short-circuit threshold levels for charge and discharge, and sets the short-circuit blanking delay time.
Cell balancing of each cell is performed via a cell bypass path, which is enabled via the internal control register
accessible via the I2C compatible interface. The maximum bypass current is set via an external series resistor
and internal FET on resistance (typical 400 Ω).
ORDERING INFORMATION
PACKAGED (1)
TA
TSSOP (PW)
bq29312PW
bq29312PWR
–25°C to 85°C
(1)
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.
PACKAGE DISSIPATION RATINGS
POWER RATING
PACKAGE
POWER RATING
TA ≤ 25°C
DERATING FACTOR
ABOVE TA ≤ 25°C
TA ≤ 70°C
TA = 85°C
PW
874 mW
6.99 W/°C
559 mW
454 mW
ABSOLUTE MAXIMUM RATINGS
over operating free-air temperature range unless otherwise noted (1) (2)
bq29312
VSS
VI
Supply voltage range
Input voltage range
PACK, BAT
–0.3 V to 34 V
VC1, VC2, VC3, VC4
–0.3 V to 34 V
SR1, SR2
–1.0 V to 1.0 V
VC5
–1.0 V to 4.0 V
VC1 to VC2, VC2 to VC3, VC3 to VC4, VC4 to
VC5
WDI, SLEEP, SCLK, SDATA
VO
Output voltage range
Continuous total power dissipation
Tstg
Storage temperature range
Lead temperature (soldering, 10 sec)
(1)
(2)
2
–0.3 to 8.5 V
ZVCHG
–0.3 V to 34 V
DSG, CHG
–0.3 V to BAT
OD
PMS
TOUT, SCLK, SDATA, CELL, XALERT
Current for cell balancing
–0.3 to 8.5 V
–0.3 V to 34 V
–0.3 V to PACK – 0.2 V
–0.3 to 7 V
10 mA
See Dissipation Rating Table
–65°C to 150°C
300°C
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.
All voltages are with respect to ground of this device except VCn – VC(n + 1), where n = 1, 2, 3, 4 cell voltage.
bq29312
www.ti.com
SLUS546E – MARCH 2003 – REVISED MARCH 2005
RECOMMENDED OPERATING CONDITIONS
MIN
Supply Voltage (BAT or PACK)
VI(STARTUP)
Start-up voltage (PACK)
Input voltage range
VIH
VIL
25
BAT
SR1, SR2
–0.5
0.5
VC5
–0.5
3.0
VCn – VC(n+1), (n = 1, 2, 3, 4 )
0
5.0
PMS
0
PACK
SLEEP
0
REG
Logic level input voltage
SCLK, SDATA, WDI
PMS logic level
PMS
PMS pull up/pull down resistance
RPMS
VO
Output voltage
OD
IO
Output current
XALERT, SDATA
II
Input current,External 3.3 V REG
capacitor
0.8×REG
REG
0
0.2 ×
REG
VPACK – 0.2
VPACK
0
0.2
100
1000
CELL
Extend CELL output filter
IOL
Input frequency
WDI high time
TA
(1)
Operating temperature
SLEEP
-0.5
C(REG)
4.7
V
V
V
V
kΩ
25
V
200
µA
±10
µA
1.0
µA
µF
R(CELL)
100
C(CELL)
100
OD
Ω
nF
1
WDI
UNIT
V
0
VIH
VIL
MAX
5.0
VC1, VC2, VC3, VC4
VI
NOM
4.5 (1)
32.768
mA
kHz
2
28
µs
–25
85
°C
V(PACK) supply voltage must rise above start-up voltage on power up to enable the internal regulator which drives REG and TOUT as
required. Once V(PACK) is above the start-up voltage, it can fall down to the minimum supply voltage and still meet the specifications of
the bq29312.
3
bq29312
www.ti.com
SLUS546E – MARCH 2003 – REVISED MARCH 2005
ELECTRICAL CHARACTERISTICS
TA = 25°C, C(REG) = 4.7 µF, BAT = 14 V (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
SUPPLY CURRENT
ICC1
Supply current 1
No load at REG, TOUT, XALERT, SCLK, and SDATA.
ZVCHG = off ,VMEN = on, WDI no clock,
Select VC5 = VC4 = 0 V
TA = –25°C to 85°C
60
90
ICC2
Supply current 2
(Depends of VM
topology selected)
No load at REG, TOUT, XALERT, SCLK, and SDATA.
ZVCHG = off, VMEN = off, WDI no clock
TA = –25°C to 85°C
25
50
µA
I(SLEEP)
Sleep current
No load at REG, TOUT, XALERT, SCLK, and
SDATA.CHG, DSG and ZVCHG = off, REG = on,
VMEN = off, WDI no clock, SLEEP = REG or OPEN
TA = –25°C to 85°C
20
40
µA
I(SHIP)
Ship current
REG, CHG, DSG and ZVCHG = off, REG = off,
VMEN = off, WDI no clock, VPACK= 0 V
TA = –25°C to 85°C
0.1
1.0
µA
100
µA
3.3 V LDO
Regulator output
voltage
V(REG)
8.0 V < BAT or PACK ≤ 25 V, IO ≤ 25 mA
–4%
3.3
2%
6.5 V < BAT or PACK ≤ 8 V, IO ≤ 25 mA
–9%
3.3
2%
–9%
3.3
2%
V
–2%
3.3
2%
V
mV
5.4 V ≤ BATor PACK ≤ 6.5 V, IO ≤ 16 mA
TA = –25°C to 85°C
4.5 V ≤ BAT or PACK ≤ 25 V, IO ≤ 2 mA
∆V(EGTEMP)
Regulator output
change with
temperature
5.4 V ≤ BAT ≤ 25 V, IO = 2 mA,
∆V(REGLINE)
Line regulation
5.4 V ≤ BAT or PACK ≤ 25 V, IO = 2 mA
3
10
BAT = 14 V, 0.2 mA ≤ IO ≤ 2 mA
7
15
BAT = 14 V, 0.2 mA ≤ IO ≤ 25 mA
40
100
∆V(REGLOAD)
Load regulation
IMAX
Current limit
V
±0.2%
TA = –25°C to 85°C
BAT = 14 V, REG = 3.0 V
25
100
BAT = 14 V, REG = 0 V
12
50
mV
mA
CELL VOLTAGE MONITOR
V(CELL
OUT)
CELL output
V(Cn) – V(Cn + 1) = 0 V, 8.0 V ≤ BAT or PACK ≤ 25 V
V(Cn) – V(Cn + 1) = 4.5 V, 8.0 V ≤ BAT or PACK ≤ 25 V
CELL output
Mode (1), 8.0 V ≤ BAT or PACK ≤ 25 V
PACK
CELL output
Mode (2)
K
CELL scale factor
REF
0.975
1%
V
–5%
PACK/
25
5%
V
K = (CELL output (VC5 = 0.0 V, VC4 = 4.5 V)
– CELL output (VC5 = VC4 = 0.0 V)/ 4.5
0.147
0.150
0.153
K = (CELL output (VC2 = 13.5 V, VC1 = 18.0 V)
– CELL output (VC2 = VC1 = 13.5 V)/ 4.5
0.147
0.150
0.153
CELL output offset
error
CELL output (VC2 = 17.0 V, VC1 = 17.0 V)
CELL output (VC2 = VC1 = 0.0 V)
R(BAL)
Cell balance internal
resistance
rds(ON) for internal FET switch at VDS = 2.0 V
4
V
0.3
–1%
VICR
(1)
(2)
0.975
Register Address =0x04, b2(CAL0) = b3(CAL1) = 1, Register Address = 0x03, b0(VMEN) = 1
Register Address = 0x03, b1(PACKOUT) = 1, b0( VMEN) = 1
–1
200
400
mV
800
Ω
bq29312
www.ti.com
SLUS546E – MARCH 2003 – REVISED MARCH 2005
ELECTRICAL CHARACTERISTICS (Continued)
TA = 25°C, C(REG) = 4.7 µF, BAT = 14 V (unless otherwise noted)
PARAMETER
TEST CONDITION
MIN
NOM
MAX
UNIT
–205
mV
OVER LOAD (OL) AND SHORT CIRCUIT (SC) DETECTION
VOL
OL detection threshold range, typical (1)
∆VOL
OL detection threshold program step
VHYS(OL)
OL detection threshold hysteresis
V(SC)
SC detection threshold range, typical (2)
∆V(SC)
SC detection threshold program step
VHYS(SC)
SC detection threshold hysteresis
–50
5
7
Charge
Discharge
OL detection threshold accuracy (1)
–475
25
Charge and Discharge
VOL = 100 mV
VSC = 100 mV (min)
SC detection threshold accuracy (2)
–100
Charge and Discharge
mV
mV
mV
–25
VOL = 205 mV (max)
V(SC_acr)
475
Discharge
Discharge
mV
13
100
Charge
VOL = 50 mV (min)
V(OL_acr)
10
40
50
60
40
50
60
90
100
110
184
205
226
80
100
120
VSC = 200 mV
180
200
220
VSC = 475 mV (max)
426
475
523
mV
mV
mV
FET DRIVE CIRCUIT
V(FETON)
Output voltage, charge and discharge FETs
on
V(FETOND)= V(BAT)– V(DSG)
VGS connect 1 MΩ
BAT= 20 V
12
15
18
V(FETONC)=V(PACK)– V(CHG)
VGS connect 1 MΩ
PACK = 20 V
12
15
18
PACK= 4.5 V
3.3
3.5
3.7
V
V(ZCHG)
ZVCHG clamp voltage
V(FETOFF)
Output voltage, charge and discharge FETs
off
V(FETOFF)= V(PACK)– V(DSG)
PACK= 16 V
0.2
V(FETOFF)=V(BAT)– V(CHG)
BAT = 16 V
0.2
tr
Rise time
CL = 4700 pF
tf
Fall time
CL = 4700 pF
VDSG :10%–90%
40
200
VCHG :10%–90%
40
200
VDSG :90%–10%
40
200
VCHG :90%–10%
40
200
50
100
V
V
µs
µs
THERMISTOR DRIVE
rDS(on)
TOUT pass-element series resistance
IO = –1 mA at TOUT pin, rds(ON) = (VREG– VO (TOUT))/1 mA,
TA = –25°C to 85°C
Ω
LOGIC
R(PUP)
Internal pullup resistance
VOL
Logic level output voltage
(1)
(2)
XALERT
TA = –25°C to 85°C
60
100
200
SDATA, SCLK,
TA = –25°C to 85°C
6
10
20
XALERT, IO = 200 µA,
TA = –25°C to 85°C
0.2
SDATA, IO = 50 µA,
TA = –25°C to 85°C
0.4
OD IO = 1 mA,
TA = –25°C to 85°C
0.6
kΩ
V
See OL register for setting detection threshold
See SC register for setting detection threshold
5
bq29312
www.ti.com
SLUS546E – MARCH 2003 – REVISED MARCH 2005
AC ELECTRICAL CHARACTERISTICS
TA = 25°C, C(REG) = 4.7 µF, BAT = 14 V (unless otherwise noted)
PARAMETER
TEST CONDITION
t(WDTINT)
WDT start-up detect time
t(WDWT)
WDT detect time
MIN
NOM MAX
250
700 2000
UNIT
ms
100
µs
AC TIMING SPECIFICATIONS (I2C COMPATIBLE SERIAL INTERFACE)
PARAMETER
MIN
MAX
UNIT
1000
ns
tr
SCLK SDATA rise time
tf
SCLK SDAT fall time
tw(H)
SCLK pulse width high
4.0
µs
tw(L)
SCLK pulse width low
4.7
µs
tsu(STA)
Setup time for START condition
4.7
µs
th(STA)
START condition hold time after which first clock pulse is generated
4.0
µs
tsu(DAT)
Data setup time
250
ns
th(DAT)
Data hold time
0
µs
tsu(STOP)
Setup time for STOP condition
4.0
µs
tsu(BUF)
Time the bus must be free before new transmission can start
4.7
tV
Clock low to data out valid
th(CH)
Data out hold time after clock low
0
fSCL
Clock frequency
0
300
tsu(STA)
tw(H)
tf
tw(L)
µs
900
ns
100
kHz
ns
tr
SCLK
tr
SDATA
Start
Condition
SDA
Input
th(STA)
1
SCLK
tf
Stop
Condition
SDA
Change
th(DAT)
tsu(DAT)
3
7
2
th(ch)
8
9
MSB
SDATA
ACK
Start Condition
tv
tsu(STOP)
SCLK
SDATA
1
MSB
2
3
7
8
9
ACK
Stop Condition
6
ns
tsu(BUF)
bq29312
www.ti.com
SLUS546E – MARCH 2003 – REVISED MARCH 2005
PIN ASSIGNMENTS
PW PACKAGE
(TOP VIEW)
1
2
3
4
5
6
7
8
9
10
11
12
BAT
DSG
VC1
VC2
VC3
VC4
VC5
SR1
SR2
WDI
CELL
GND
24
23
22
21
20
19
18
17
16
15
14
13
OD
PMS
PACK
ZVCHG
CHG
SLEEP
REG
TOUT
XALERT
GND
SDATA
SCLK
Terminal Functions
TERMINAL
NAME
NO.
DESCRIPTION
BAT
1
Diode protected BAT+ terminal and primary power source.
DSG
2
Push-pull output discharge FET gate drive
VC1
3
Sense voltage input terminal for most positive cell and balance current input for most positive cell.
VC2
4
Sense voltage input terminal for second most positive cell, balance current input for second most positive cell and
return balance current for most positive cell.
VC3
5
Sense voltage input terminal for third most positive cell, balance current input for third most positive cell and return
balance current for second most positive cell.
VC4
6
Sense voltage input terminal for least positive cell, balance current input for least positive cell and return balance
current for third most positive cell.
VC5
7
Sense voltage input terminal for most negative cell, return balance current for least positive cell.
SR1
8
Current sense positive terminal when charging relative to SR2
SR2
9
Current sense negative terminal when discharging relative to SR2 current sense terminal
WDI
10
Digital input that provides the timing clock for the OC and SC delays and also acts as the watchdog clock.
CELL
11
Output of scaled value of the measured cell voltage.
GND
12
Analog ground pin and negative pack terminal
SCLK
13
Open-drain bidirectional serial interface clock with internal 10 kΩ pull-up to V(REG).
SDATA
14
Open-drain bidirectional serial interface data with internal 10 kΩ pull-up to V(REG).
GND
15
Connect to GND
XALERT
16
Open-drain output used to indicate status register changes. With internal 100 kΩ pull-up to V(REG)
TOUT
17
Provides thermistor bias current
REG
18
Integrated 3.3-V regulator output
SLEEP
19
This pin is pulled up to V(REG) internally, open or H level makes Sleep mode
CHG
20
Push-pull output charge FET gate drive
ZVCHG
21
The ZVCHG FET drive is connected here
PACK
22
PACK positive terminal and alternative power source
PMS
23
0-V charge configuration select pin, CHG terminal ON/OFF is determined by this pin.
OD
24
NCH FET open drain output
7
bq29312
www.ti.com
SLUS546E – MARCH 2003 – REVISED MARCH 2005
FUNCTIONAL BLOCK DIAGRAM
PACK-
GG VDD
PACK+
R(ZVCHG)
C (REG)
PMS
ZVCHG
REG
0.2 A
Current Source
CHG
DSG
BAT
ZVCHG_ON
Gate Driver CHG_ON
DSG_ON
+
_
-
PACK
FET
Logic
REG
3.3V LDO
POR
SLEEP
CONTROL
32kHz INPUT
FROM GG
SLEEP
Watchdog
Timer
WDI
GG INTERFACE
SDATA
GG INTERFACE
SCLK
SDATA
SCLK
REG
SERIAL INTERFACE
Registers
Status
Function Ctl
CELL 2
VC4
CELL 1
VC5
Drive
Control
TOUT
C THERM
THERMISTOR
R CELL
VCELL
OCDV
OCDT
Over-Load
Comparator
SCC
Open
Drain
Output
C CELL
GG ANALOG
INPUT
OVER_CURRENT
SR1
DELAY
SHORT_CIRCUIT
Short Circuit
Comparator
R SNS
SR2
GND
8
GG TS
INPUT
R THERM
Cell Voltage
Translation
CELL_SEL
SCD
OD
CELL 3
VC3
State Ctl
200 k
OPEN DRAIN
OUTPUT
Power
Mode
Circuit
CELL 4
VC2
Output Ctl
ALERT TO GG
XALERT
SHIP_ON
SLEEP_ON
CELL1..4
200 k
Cell
Selection
Switches
VC1
bq29312
www.ti.com
SLUS546E – MARCH 2003 – REVISED MARCH 2005
STATE DIAGRAM
No Power
SHIP MODE EXIT BY POWER
SUPPLY TO PACK
POWER SUPPLY TO PACK
INITIALIZE
FETS: OFF(*2)
REG: start Working
I2C: OFF
CURRENT FAULT : OFF
CELL MONITOR : OFF
WATCHDOG : OFF
THERMISTOR PWER CTRL : OFF
REG >2.4 V
IFAULT
RESET CURRENT LATCH
HOST FAULT MODE
FETS: OFF
REG: ON
I2C: ON
CURRENT FAULT : OFF
CELL MONITOR : OFF
WATCHDOG : ON
THERMISTOR PWER CTRL : OFF
REG < 2.3 V
NORMAL MODE
FETS: ON *2
REG: ON
I2C: ON
CURRENT FAULT : ON
CELL MONITOR : ON
WATCHDOG : ON
THERMISTOR PWER CTRL : ON
HOST CLOCK STOP
RESET WDTF LATCH
STATE CTL REGISTER b1 = 1
AND NO SUPPLY POWER TO PACK
SLEEP MODE EXIT BY
STATE CTL REGISTER b1 = 0
AND SLEEP PIN = GND
*1
STATE CTL REGISTER b0 = 1
or SLEEP PIN = REG or OPEN
*1
CURRENT DETECT MODE
SLEEP MODE
SHIP MODE
FETS: OFF
REG: ON
I2C: ON
CURRENT FAULT : ON
CELL MONITOR : ON
WATCHDOG : ON
THERMISTOR PWER CTRL : ON
FETS: OFF
REG: ON
I2C: ON
CURRENT FAULT : OFF
CELL MONITOR : OFF
WATCHDOG : OFF
THERMISTOR PWER CTRL : OFF
FETS: OFF
REG: OFF
I2C: OFF
CURRENT FAULT : OFF
CELL MONITOR : OFF
WATCHDOG : OFF
THERMISTOR PWER CTRL : OFF
SHIP MODE SET BY
STATE CTL REGISTER
b1 = 1 AND NO SUPPLY
POWER TO PACK
SHIP MODE SET BY STATE CTL REGISTER
b1 = 1 AND NO SUPPLY POWER TO PACK
Interrupt Request When
Enrering These States
*1: Interrupt Request is Granted When Only External Sleep Pin Changes
*2: When PMS connect to Pack, Default State of CHG FET is ON.
9
bq29312
www.ti.com
SLUS546E – MARCH 2003 – REVISED MARCH 2005
FUNCTIONAL DESCRIPTION
Low-Dropout Regulator (REG)
The inputs for this regulator can be derived from the battery cell stack (BAT) or the pack positive terminal
(PACK). The output is typically 3.3 V with the minimum output capacitance for stable operation is 4.7 µF and is
also internally current limited. During normal operation, the regulator limits output current to typically 50 mA.
Initialization
The bq29312 internal control circuit is powered by the REG voltage, which it also monitors. When the voltage at
REG falls below 2.3 V, the internal circuit turns off the FETs and disables all controllable functions, including the
REG and TOUT outputs. REG does not start up unless a voltage above V(STARTUP) is supplied to the PACK
terminal. After the regulator has started, based on PACK voltage, it keeps operating through the BAT input, even
if the PACK voltage is removed. If the BAT input is below the minimum operating range, then the bq29312 does
not operate if the supply to the PACK input is removed. After start up, when the REG voltage is above 2.4 V, the
bq29312 is in Normal mode.
The initial state of the CHG output depends on the PMS input. If PMS = PACK then CHG = ON however, if PMS
= GND then CHG = OFF.
Overload Detection
The overload detection is used to detect abnormal currents in the discharge direction. This feature is used to
protect the pass FETs, cells and any other inline components from excessive current conditions. The detection
circuit also incorporates a blanking delay before driving the control for the pass FETs to the OFF state. The
overload sense voltage is set in the OLV register, and delay time is set in the OLT register. The overload
threshold can be programmed from 50 mV to 205 mV in 5-mV steps with the default being 50 mV and hysteresis
of 10 mV.
Short-Circuit Detection
The short current circuit detection is used to detect abnormal current in either the charge or discharge direction.
This safety feature is used to protect the pass FETs, cells, and any other inline components from excessive
current conditions. The detection circuit also incorporates a blanking delay before driving the control for the pass
FETs to the OFF state. The short- circuit thresholds and delay time are set in the SCC and SCD registers
respectively where SCC is for charging and SCD is for discharge. The short-circuit threshold can be programmed
from 100 mV to 475 mV in 25-mV steps with the default being 100 mV and hysteresis of 50 mV.
Overload and Short-Circuit Delay
The overload delay (default =1 ms) allows the system to momentarily accept a high current condition without
disconnecting the supply to the load. The delay time can be increased via the OLT register, which can be
programmed for a range of 1 ms to 31 ms with steps of 2 ms.
The short-circuit delay (default = 0 µs) is programmable in the SCC and SCD registers. This register can be
programmed from 0 µs to 915 µs with steps of 61 µs.
Overload and Short-Circuit Response
When an overload or short-circuit fault is detected, the FETs are turned off. The STATUS (b0…b2) register
reports the details of short-circuit (charge), short-circuit (discharge), and overload. The respective STATUS
(b0…b2) bits are set to 1 and the XALERT output is triggered. This condition is latched until the CONTROL (b0)
is set and then reset. If a FET is turned on via resetting CONTROL (b0) and the error condition is still present on
the system, then the device reenters the protection response state.
10
www.ti.com
bq29312
SLUS546E – MARCH 2003 – REVISED MARCH 2005
FUNCTIONAL DESCRIPTION (continued)
Cell Voltage
The cell voltage is translated to allow a system host to measure individual series elements of the battery. The
series element voltage is translated to a GND-based voltage equal to 0.15 ±0.002 of the series element voltage.
This provides a range from 0 V to 4.5 V. The translation output is inversely proportional to the input using the
following equation.
Where, V(CELL OUT) = –K × V(CELL IN) + 0.975 (V)
Programming CELL_SEL (b1, b0) selects the individual series element. The CELL_SEL (b3, b2) selects the
voltage monitor mode, cell monitor, offset etc.
Calibration of Cell Voltage Monitor Amplifier Gain
The cell voltage monitor amplifier has an offset and to increase accuracy this can be calibrated.
There are a couple of method by calibration circumstance.
The following procedure shows how to measure and calculate the offset and gain as one of example.
• Step 1
– Set CAL1=1, CAL0=1, CELL1=0, CELL0=0, VMEN=1
– VREF is trimmed to 0.975 V within ±1%, measuring VREF eliminates its error.
– Measure internal reference voltage VREF from VCELL directly.
– VREF=measured reference voltage
• Step 2
– Set CAL1=0, CAL0=0, CELL1=0, CELL0=0, VMEN=1
– The output voltage includes the offset and represented by:
VO(4-5) = VREF + (1 + K) × VOS (V)
Where K = CELL Scaling Factor
– VOS = Offset voltage at input of the internal operational-amplifier
• Step 3
– Set CAL1=1, CAL0=0, CELL1=0, CELL0=0, VMEN=1
– Measuring scaled REF voltage through VCELL amp.
– The output voltage includes the scale factor error and offset and is represented by:
V(OUTR) = VREF + (1 + K) × VOS– K × VREF (V)
• Step 4
– Calculate (VO(4-5)– V(OUTR)/VREF
– The result is the actual scaling factor, K(ACT) and is represented by:
K(ACT) = (VO(4-5)– V(OUTR))/VREF = (VREF + (1 + K) × VOS) - (VREF + (1 + K) × VOS– K × VREF)/ VREF = K ×
VREF/VREF = K
• Step 5
– Calculate the actual offset value where:
VOS(ACT) = (VO(4-5)– VREF)/(1 + K(ACT))
• Step 6
– Calibrated cell voltage is calculated by:
VCn – VC(n+1) = {VREF + (1 + K(ACT) ) × VOS(ACT)– V(CELLOUT)}/K(ACT) – {VO(4-5)– V(CELLOUT)}/K(ACT)
11
bq29312
SLUS546E – MARCH 2003 – REVISED MARCH 2005
www.ti.com
FUNCTIONAL DESCRIPTION (continued)
For
•
•
•
improved measurement accuracy, VOS(ACT) for each cell voltage should be measured.
Set CAL1=0, CAL0=0, CELL1=0, CELL0=1, VMEN=1
Set CAL1=0, CAL0=0, CELL1=1, CELL0=0, VMEN=1
Set CAL1=0, CAL0=0, CELL1=1, CELL0=1, VMEN=1
Measuring VO(3-4) , VO(2-3), VO(1-2),
• VC4 – VC5 = {VO(4-5)– V(CELLOUT)}/ K(ACT)
• VC3 – VC4 = {VO(3-4)– V(CELLOUT)}/ K(ACT)
• VC2 – VC3 = {VO(2-3)– V(CELLOUT)}/ K(ACT)
• VC1 – VC2 = {VO(1-2)– V(CELLOUT)}/ K(ACT)
Cell Balance Control
The cell balance control allows a small bypass path to be controlled for any one series element. The purpose of
this bypass path is to reduce the current into any one cell during charging to bring the series elements to the
same voltage. Series resistors placed between the input pins and the positive series element nodes control the
bypass current value. Individual series element selection is made using bits 4 through 7 of the CELL_SEL
register.
Thermistor Drive Circuit (TOUT)
The TOUT pin can be enabled to drive a thermistor from REG. The typical thermistor resistance is 10 kΩ at
25°C. The default-state is OFF to conserve power. The maximum output impedance is 100 Ω. TOUT is enabled
in FUNCTION CTL Register (bit 5).
Open Drain Drive Circuit (OD)
The open drain output has 1-mA current source drive with a maximum output voltage of 25 V. The OD output is
enabled or disabled by OUTPUT CTL Register (bit 4) and has a default state of OFF.
XALERT (XALERT)
XALERT is driven low when an OL or SC current fault is detected, if the SLEEP pin changes state or a watchdog
fault occurs. To clear XALERT, toggle (from 0, set to 1 then reset to 0) OUTPUT CTL (bit 0), then read the
STATUS register.
Latch Clear (LTCLR)
When a current limit fault or watch dog timer fault occurs, the state is latched. To clear these faults, toggle (from
0, set 1 then reset to 0) LTCLR in the OUTPUT CTL register (bit 0).
Figure 1 is the LTCLR and XALERT clear example after sensing short-circuit.
12
bq29312
www.ti.com
SLUS546E – MARCH 2003 – REVISED MARCH 2005
FUNCTIONAL DESCRIPTION (continued)
I2C
OUTPUT CTRL (b2-b1)
DSG, CHG
OUTPUT CTRL (b3)
XZVCHG
LTCLR
Write = 1
LTCLR
Write = 0
Read STATUS
Register
Staied Disable
Access Enable
Staied Disable
Access Enable
OUTPUT CTRL (b0)
LTCLR
Short Current Timeout
in Discharge Direction
STATUS (b0)
SCDSG
XALERT Pin
Figure 1. LTCLR and XALERT Clear Example After Sensing Short LTCLR and XALER Clear Example
2-, 3-, or 4-Cell Configuration
In a 3-cell configuration, VC1 is shorted to VC2. In a 2-cell configuration, VC1 and VC2 are shorted to VC3.
13
bq29312
www.ti.com
SLUS546E – MARCH 2003 – REVISED MARCH 2005
FUNCTIONAL DESCRIPTION (continued)
Watchdog Input (WDI)
The WDI input is required as a time base for delay timing when determining overload and short-circuit delay
periods and is used as part of the system watchdog.
Initially the watchdog monitors the hosts oscillator start up, if there is no response from the host within 700 ms of
the bq29312 reaching its minimum operating voltage, then the bq29312 turns both CHG, DSG and ZVCHG FETs
OFF.
Once the watchdog has been started during this wake up period, it monitors the host for an oscillation stop
condition, which is defined as a period of 100 µs (typ) where no clock input is received. If an oscillator stop
condition is identified, then the watchdog turns the CHG, DSG and ZVCHG FETs OFF. When the host clock
oscillation is started, WDF is released, but the flag is latched until LTCLR is toggled.
REG
GG 32 kHz Output
GG Clock Never Starts
tWDTINT ∼ 700 mS
EXT FET Control
CHG, DSG and
ZVCHG = OFF
Figure 2. Watchdog Timing Chart—WDI Fault at Startup
REG
GG 32 kHz Output
GG Clock Stop
Watchdog Sense
tWDWT About 100 µS
EXT FET Control
CHG, DSG and
ZVCHG = OFF
Figure 3. Watchdog Timing Chart—WDI Fault After Startup
DSG and CHG FET Driver Control
The bq29312 drives the DSG, CHG, and ZVCHG FET off if an OL or SC safety threshold is breached depending
on the current direction. The host can force any FET on or off only if the bq29312 integrated protection control
allows. The DSG and CHG FET drive gate-to-drain voltage is clamped to 15 V (typ).
14
bq29312
www.ti.com
SLUS546E – MARCH 2003 – REVISED MARCH 2005
FUNCTIONAL DESCRIPTION (continued)
The default-state of the CHG and DSG FET drive is off, when PMS = GND. A host can control the FET drive by
programming OUTPUT CTL (b3...b1) where b1 is used to control the discharge FET, b2 is used to control the
charge FET and b3 is used to control the ZVCHG FET. These controls are only valid when not in the initialized
state. The CHG drive FET can be powered by PACK and the DSG FET can be powered by BAT.
Precharge and 0 V Charging—Theory of Operation
The bq29312 supports both a charger that has a precharge mode and one that does not. The bq29312 also
supports charging even when the battery falls to 0 V. Detail is described in the application section.
SLEEP Control Input (SLEEP)
The SLEEP input is pulled-up internally to REG. When SLEEP is pulled to REG, the bq29312 enters the SLEEP
mode. The SLEEP mode disables all the FET outputs and the OL, SC and watchdog faults are also disabled.
The RAM configuration is still valid on exit of the SLEEP mode. The host can force the bq29312 into SLEEP
mode via register control also.
Table 1. SLEEP Control Input
ITEM
SLEEP
FUNCTION
I2C Read/Write
Active
REG Output
Active
I2C READ/WRITE
EXIT SLEEP
External pin control:
CHG, DSG, ZVCHG, TOUT, OD
OC and SC protection:
Write is available,
but read is disabled
SCD, SCC and OCD
CELL Translation
Last pre-sleep entry configuration is valid.(If change
configuration, latest write data is valid.)
Disabled
PACKOUT, VMEN
Cell Balancing:
CB[3:0]
Watchdog: WDDIS
Power Modes
The bq29312 has three power modes, Normal, Sleep, and Ship. The following table outlines the operational
functions during these power modes.
Table 2. Power Modes
POWER
MODE
Normal
TO ENTER POWER MODE
TO EXIT POWER
MODE
SLEEP = GND and
STATE CTL( b0) = 0 and
STATE CTL( b1) = 0
MODE DESCRIPTION
The battery is in normal operation with protection, power
management and battery monitoring functions available and
operating.
The supply current of this mode varies as the host can enable
and disable various power management features.
Sleep
{SLEEP = REG (floating) or
STATE CTL( b0) = 1 } and
STATE CTL( b1) = 0
SLEEP = GND and
STATE CTL( b0) = 0
All functions stop except LDO and I2C interface.
On entry to this mode, all registers are masked off keeping their
state.
The host controller can change the RAM registers via the I2C
interface, but reading data is disabled until exit of Sleep mode.
Ship
STATE CTL( b1) = 1
And supply at the PACK pin is
removed
Supply voltage to PACK
The bq29312 is completely shut down as in the sleep mode. In
addition the REG output is disabled, I2C interface is powered
down and memory is not valid.
15
bq29312
www.ti.com
SLUS546E – MARCH 2003 – REVISED MARCH 2005
Communications
The I2C compatible serial communications provides read and write access to the bq29312 data area. The data is
clocked via separate data (SDATA) and clock (SCLK) pins. The bq29312 acts as a slave device and does not
generate clock pulses. Communication to the bq29312 is provided from GPIO pins or an I2C supporting port of a
host system controller. The slave address for the bq29312 is 7 bits and the value is 0100 000 (0x20).
I2C ADDRESS +R/W BIT
(MSB)
I2C
(MSB)
Write (1)
0
Read
(1)
1
(LSB)
ADDRESS (0x20)
0
0
(LSB)
0
0
0
0
1
Bit 0: 0 = write, 1= read
The bq29312 does not have the following functions compatible with the I2C specification.
• The bq29312 is always regarded as a slave.
• The bq29312 does not return a NACK for an invalid register address.
• The bq29312 does not support the general code of the I2C specification, and therefore does not return an
ACK.
• The bq29312 does not support the address auto increment, which allows continuous reading and writing.
• The bq29312 allows data to written or read from the same location without resending the location address.
…
SCLK
SDATA
A6
Start
…
A5 A4 … A0
R7
R/W ACK
0
0
Slave Address
R6
R5
…
… R0
ACK
0
D7
D6
Register Address
D5 … D0 ACK
0
Data
Stop
Note: Slave = bq29312
Figure 4. I2C-Bus Write to bq29312
…
SCLK
SDATA
A6
…
A5 … A0 R/W
ACK
R7
R6 … R0
ACK
0
0
A6
…
A0
R/W ACK
0
Slave Address
Start
…
1
Register Address
0
Slave Address
D7
D6 … D0 NACK
Slave Drives
The Data
Master Drives
NACK and Stop
Data
Note: Slave = bq29312
Stop
Figure 5. I2C-Bus Read from bq29312: Protocol A
…
SCLK
SDATA
Start
A6
…
A5 … A0 R/W ACK
0
Slave Address
0
R7
…
R6 … R0 ACK
Register
Address
A6
A5 …
…
A0
R/W ACK
0
Stop Start
Slave Address
D7 … D0 NACK
Slave Drives
The Data
Stop
Master Drives
NACK and Stop
Note: Slave = bq29312
Figure 6. I2C-Bus Read from bq29312: Protocol B
16
bq29312
www.ti.com
SLUS546E – MARCH 2003 – REVISED MARCH 2005
Register Map
The bq29312 has 9 addressable registers. These registers provide status, control, and configuration information
for the battery protection system.
Table 3. Addressable Registers
ADDR
TYPE
STATUS
NAME
0x00
R
DESCRIPTION
OUTPUT CTL
0x01
R/W
Output pin control from system host
STATE CTL
0x02
R/W
State control
FUNCTION CTL
0x03
R/W
Function control
CELL _SEL
0x04
R/W
Battery cell select for cell translation and balance bypass and select mode for calibration
OLV
0x05
R/W
Overload threshold voltage
OLT
0x06
R/W
Overload delay time
SCC
0x07
R/W
Short-circuit current threshold voltage and delay for charge
SCD
0x08
R/W
Short-circuit current threshold voltage and delay for discharge
Status register
STATUS : Status register
STATUS REGISTER (0x00)
7
6
5
4
3
2
1
0
0
0
ZVCLMP
SLEEPDET
WDF
OL
SCCHG
SCDSG
The STATUS register provides information about the current state of the bq29312. Reading the STATUS register
clears the XALERT pin.
STATUS b0 (SCDSG): This bit indicates a short-circuit in the discharge direction.
0 = Current below the short-circuit threshold in the discharge direction (default).
1 = Current greater than or equal to the short-circuit threshold in the discharge direction.
STATUS b1 (SCCHG): This bit indicates a short-circuit in the charge direction.
0 = Current below the short-circuit threshold in the charge direction (default).
1 = Current greater than or equal to the short-circuit threshold in the charge direction.
STATUS b2 (OL): This bit indicates an overload condition.
0 = Current less than or equal to the overload threshold (default).
1 = Current greater than overload threshold.
STATUS b3 (WDF): This bit indicates a watchdog fault condition has occurred.
0 = 32 kHz oscillation is normal (default).
1 = 32 kHz oscillation stopped or not started and the watchdog has timed out.
STATUS b4 (SLEEPDET): This bit indicates the bq29312 is SLEEP mode.
0 = bq29312 is not SLEEP mode (default).
1 = bq29312 is SLEEP mode.
STATUS b5 (ZVCLMP): This bit indicates ZVCHG output is clamped.
0 = ZVCHG pin is not clamped (default).
1 = ZVCHG pin is clamped.
17
bq29312
www.ti.com
SLUS546E – MARCH 2003 – REVISED MARCH 2005
OUTPUT CTL: Output Control Register
OUTPUT CTL REGISTER (0x01)
7
6
5
4
3
2
1
0
0
0
0
OD
XZVCHG
CHG
DSG
LTCLR
The OUTPUT CTL register controls the outputs of the bq29312 and can be used to clear certain states.
OUTPUT CTL b0 (LTCLR): When a current limit fault or watchdog timer fault is latched, this bit releases the fault
latch when toggled from 0 to 1 and back to 0 (default =0).
0 = (default)
0->1 ->0 clears the fault latches
OUTPUT CTL b1 (DSG): This bit controls the external discharge FET.
0 = discharge FET is off and is controlled by the system host (default).
1 = discharge FET is on and the bq29312 is in normal operating mode.
OUTPUT CTL b2 (CHG): This bit controls the external charge FET.
PMS=GND
0 = charge FET is off and is controlled by the system host (default).
1 = charge FET is on and the bq29312 is in normal operating mode.
PMS=PACK
0 = charge FET is off and is controlled by the system host.
1 = charge FET is on and the bq29312 is in normal operating mode (default).
OUTPUT CTL b3 (XZVCHG): This bit controls the external ZVCHG FET.
0 = ZVCHG FET is on and is controlled by the system host (default).
1 = ZVCHG FET is off and the bq29312 is in normal operating mode.
OUTPUT CTL b4 (OD): This bit enables or disables the OD output.
0 = OD is high impedance (default).
1 = OD output is active (GND).
STATE CTL: State Control Register
STATE CTL REGISTER (0x02)
7
6
5
4
3
2
1
0
0
0
0
0
0
WDDIS
SHIP
SLEEP
The STATE CTL register controls the state of the bq29312.
STATE CTL b0 (SLEEP): This bit is used to enter the sleep power mode.
0 = bq29312 exits sleep mode (default).
1 = bq29312 enters the sleep mode.
STATE CTL b1 (SHIP): This bit is used to enter the ship power mode when pack supply voltage is not applied.
0 = bq29312 in normal mode (default).
1 = bq29312 enters ship mode when pack voltage is removed.
STATE CTL b2 (WDDIS): This bit is used to enable or disable the watchdog timer function.
0 = enable clock monitoring (default).
1 = disable clock monitoring.
NOTE: Use caution when setting the WDDIS. For example, when the 32-kHz input fails, the overload and
short-circuit delay timers no longer function because they use the same WDI input. If the WDI input clock stops,
these current protections do not function. WDF should be enabled at any time for maximum safety. If the
watchdog function is disabled, the CHG and DSG FETs should be turned off.
18
bq29312
www.ti.com
SLUS546E – MARCH 2003 – REVISED MARCH 2005
FUNCTION CTL: Function Control Register
FUNCTION CTL REGISTER (0x03)
7
6
5
4
3
2
1
0
0
0
TOUT
XSCD
SSCC
XOL
PACKOUT
VMEN
The FUNCTION CTL register enables and disables functons of the bq29312.
FUNCTION CTL b0 (VMEN): This bit enables or disables the cell and battery voltage monitoring function.
0 = disable voltage monitoring (default). CELL output is pulled down to GND level.
1 = enable voltage monitoring.
FUNCTION CTL b1 (PACKOUT): This bit is used to translate the PACK input to the CELL pin when VMEN=1
The pack voltage is divided by 25 and is presented on CELL regardless of the CELL_SEL register settings.
0 = disable PACK OUT (default).
1 = enable PACK OUT.
FUNCTION CTL b2 (XOL): This bit enables or disables the over current sense function.
0 = enable over load sense (default).
1 = disable over load sense.
FUNCTION CTL b3 (XSCC): This bit enables or disables the short current sense function of charging.
0 = enable short-circuit current sense in charge direction (default).
1 = disable short-circuit current sense in charge direction.
FUNCTION CTL b4 (XSCD): This bit enables or disables the short current sense function of discharge.
0 = enable short-circuit current sense in discharge direction (default).
1 = disable short-circuit current sense in discharge direction.
FUNCTION CTL b5 (TOUT): This bit controls the power to the thermistor.
0 = thermistor power is off (default).
1 = thermistor power is on.
19
bq29312
www.ti.com
SLUS546E – MARCH 2003 – REVISED MARCH 2005
CELL SEL: Cell Select Register
CELL_SEL REGISTER (0x04)
7
6
5
4
3
2
1
0
CB3
CB2
CB1
CB0
CAL1
CAL0
CELL1
CELL0
This register determines cell selection for voltage measurement and translation, cell balancing and the
operational mode of the cell voltage monitoring.
CELL_SEL b0–b1 (CELL0–CELL1): These two bits select the series cell for voltage measurement translation.
CELL1
CELL0
0
0
VC4–VC5, Bottom series element (Default)
SELECTED CELL
0
1
VC4–VC3, Second lowest series element
1
0
VC3–VC2, Second highest series element
1
1
VC1–VC2, Top series element
CELL_SEL b2–b3 (CAL1, CAL0): These bits determine the mode of the voltage monitor block.
CAL1
CAL0
0
0
Cell translation for selected cell (default)
SELECTED MODE
0
1
Offset measurement for selected cell
1
0
Monitor the VREF value for gain calibration
1
1
Monitor the VREF directly value for gain calibration, bypassing the translation circuit
CELL_SEL b4–b7 (CB0–CB3): These 4 bits select the series cell for cell balance bypass path.
CELL SEL b4 (CB0): This bit enables or disables the bottom series cell balance charge bypass path
0 = disable bottom series cell balance charge bypass path (default).
1 = enable bottom series cell balance charge bypass path.
CELL SEL b5 (CB1): This bit enables or disables the second lowest series cell balance charge bypass path.
0 = disable series cell balance charge bypass path (default).
1 = enable series cell balance charge bypass path.
CELL SEL b6 (CB2): This bit enables or disables the second highest cell balance charge bypass path.
0 = disable series cell balance charge bypass path (default).
1 = enable series cell balance charge bypass path.
CELL SEL b7 (CB3): This bit enables or disables the highest series cell balance charge bypass path.
0 = disable series cell balance charge bypass path (default).
1 = enable series cell balance charge bypass path.
20
bq29312
www.ti.com
SLUS546E – MARCH 2003 – REVISED MARCH 2005
OLV: Overload Voltage Threshold Register
OLV REGISTER (0x05)
7
6
5
4
3
2
1
0
0
0
0
OLV4
OLV3
OLV2
OLV1
OLV0
OLV (b4–b0): These five bits select the value of the over load threshold with a default of 00000.
OLV (b4–b0) configuration bits with corresponding voltage threshold
00000
0.050 V
01000
0.090 V
10000
0.130 V
11000
0.170 V
00001
0.055 V
01001
0.095 V
10001
0.135 V
11001
0.175 V
00010
0.060 V
01010
0.100 V
10010
0.140 V
11010
0.180 V
00011
0.065 V
01011
0.105 V
10011
0.145 V
11011
0.185 V
00100
0.070 V
01100
0.110 V
10100
0.150 V
11100
0.190 V
00101
0.075 V
01101
0.115 V
10101
0.155 V
11101
0.195 V
00110
0.080 V
01110
0.120 V
10110
0.160 V
11110
0.200 V
00111
0.085 V
01111
0.125 V
10111
0.165 V
11111
0.205 V
OLT: Overload Blanking Delay Time Register
OLT REGISTER (0x06)
7
6
5
4
3
2
1
0
0
0
0
0
OLT3
OLT2
OLT1
OLT0
OLT(b3–b0): These four bits select the value of the delay time for overload with a default of 0000.
OLT(b3–b0) configuration bits with corresponding delay time
0000
1 ms
0100
9 ms
1000
17 ms
1100
25 ms
0001
3 ms
0101
11 ms
1001
19 ms
1101
27 ms
0010
5 ms
0110
13 ms
1010
21 ms
1110
29 ms
0011
7 ms
0111
15 ms
1011
23 ms
1111
31 ms
SCC: Short Circuit in Charge Configuration Register
SCC REGISTER (0x07)
7
6
5
4
3
2
1
0
SCCT3
SCCT2
SCCT1
SCCT0
SCCV3
SCCV2
SCCV1
SCCV0
This register selects the short-circuit threshold voltage and delay for charge.
SCC(b3–b0) : These bits select the value of the short-circuit voltage threshold with 0000 as the default.
SCC(b3–b0) with corresponding SC threshold voltage
0000
0.100 V
0100
0.200 V
1000
0.300 V
1100
0.400 V
0001
0.125 V
0101
0.225 V
1001
0.325 V
1101
0.425 V
0010
0.150 V
0110
0.250 V
1010
0.350 V
1110
0.450 V
0011
0.175 V
0111
0.275 V
1011
0.375 V
1111
0.475 V
21
bq29312
www.ti.com
SLUS546E – MARCH 2003 – REVISED MARCH 2005
SCC(b7–b4): These bits select the value of the short-circuit delay time. Exceeding the short-circuit voltage
threshold for longer than this period will turn off the corresponding CHG, DSG, and ZVCHG output. 0000 is the
default.
SCC(b7–b4) with corresponding SC delay time
0000
0 µs
0100
244 µs
1000
488 µs
1100
732 µs
0001
61 µs
0101
305 µs
1001
549 µs
1101
793 µs
0010
122 µs
0110
366 µs
1010
610 µs
1110
854 µs
0011
183 µs
0111
427 µs
1011
671 µs
1111
915 µs
SCD: Short Circuit in Discharge Configuration Register
SCD REGISTER (0x08)
7
6
5
4
3
2
1
0
SCDT3
SCDT2
SCDT1
SCDT0
SCDV3
SCDV2
SCDV1
SCDV0
This register selects the short-circuit threshold voltage and delay for discharge.
SCD(b3–b0) with corresponding SC threshold voltage with 0000 as the default.
SCD(b3–b0): These bits select the value of the short-circuit voltage threshold
0000
0.10 V
0100
0.20 V
1000
0.30 V
1100
0.40 V
0001
0.125 V
0101
0.225 V
1001
0.325 V
1101
0.425 V
0010
0.150 V
0110
0.250 V
1010
0.350 V
1110
0.450 V
0011
0.175 V
0111
0.275 V
1011
0.375 V
1111
0.475 V
SCD(b7–b4): These bits select the value of the short-circuit delay time. Exceeding the short-circuit voltage
threshold for longer than this period will turn off the corresponding CHG, DSG, and ZVCHG output as has 0000
as the default.
SCD(b7-b4) with corresponding SC delay time
22
0000
0 µs
0100
244 µs
1000
488 µs
1100
732 µs
0001
61 µs
0101
305 µs
1001
549 µs
1101
793 µs
0010
122 µs
0110
366 µs
1010
610 µs
1110
854 µs
0011
183 µs
0111
427 µs
1011
671 µs
1111
915 µs
bq29312
www.ti.com
SLUS546E – MARCH 2003 – REVISED MARCH 2005
APPLICATION INFORMATION
Precharge and 0-V Charging—Theory of Operation
In order to charge, the charge FET (CHG-FET) must be turned on to create a current path. When the V(BAT) is 0
V and CHG-FET = ON, the V(PACK) is as low as the battery voltage. In this case, the supply voltage for the device
is too low to operate. There are 3 possible configurations for this function and the bq29312 can be easily
configured according to the application needs. The 3 modes are 0-V Charge FET Mode, Common FET Mode
and Precharge FET Mode.
1. 0-V Charge FET Mode – Dedicates a precharge current path using an additional FET (ZVCHG-FET) to
sustain the PACK+ voltage level. The host charger is expected to provide a precharge function.
2. Common FET Mode – Does not use a dedicated precharge FET. The charge FET (CHG-FET) is assured to
be set to ON state as default. The charger is expected to provide a precharge function.
3. Precharge FET Mode – Dedicates a precharge current path using an additional open drain (OD) pin drive
FET (PCHG-FET) FET to sustain the PACK+ voltage level. The charger does not provide any precharge
function.
0-V Charge FET Mode
In this mode, a dedicated precharge current path using an additional FET (ZVCHG-FET) is required to sustain a
suitable PACK+ voltage level. The charger is expected to provide the precharge function in this mode where the
precharge current level is suitable to charge cells below a set level, typically below 3 V per cell. When the lowest
cell voltage rises above this level, then a fast charging current is applied by the charger.
The circuit diagram for this method is shown in Figure 7, showing how the additional FET is added in parallel
with the charge FET (CHG-FET).
R(ZVCHG)
Charger
ZVCHG-FET
CC
DC Input
IZVCHG
DSG-FET
CHG-FET
DSG
BAT
CHG
bq29312
Pack+
IFASTCHG
PACK
ZVCHG
Battery
REG
OD
CV
PMS
4.7 µF
NC
I(ZVCHG) = 0 V Percharge Current
I(FASTCHG) = Fast Current
Figure 7. 0-V Charge FET Mode Circuit
23
bq29312
www.ti.com
SLUS546E – MARCH 2003 – REVISED MARCH 2005
APPLICATION INFORMATION (continued)
In order to pass 0 V or precharge current an appropriate gate-source voltage V(GS), for ZVCHG-FET must be
applied. Here, V(PACK) can be expressed in terms of V(GS) as follows:
V(PACK) = V(ZVCHG) + V(GS)(ZVCHG-FET gate - source voltage)
ID
Point B
Point A
Precharge
Current
VGS
VDS
Figure 8. Drain Current vs Drain-Source Voltage Characteristics
In the bq29312, the initial state is for CHG-FET = OFF and ZVCHG-FET = ON with the V(ZVCHG) clamped at 3.5 V
initially. Then the charger applies a constant current and raises V(PACK) high enough to pass the precharge
current, point A. For example, if the V(GS) is 2 V at this point, V(PACK) is 3.5 V + 2 V = 5.5 V. Also, the
ZVCHG-FET is used in its MOS saturation region at this point so that V(DS) is expressed as follows:
V(PACK) = V(BAT) + VF + VDS(ZVCHG-FET)
where V(F) = 0.7 V is the forward voltage of a DSG-FET back diode and is typically 0.7 V.
This derives the following equation:
VDS = 4.8 V - V(BAT)
As the battery is charged V(BAT) increases and the V(DS) voltage decreases reaching its linear region. For
example: If the linear region is 0.2 V, this state continues until V(BAT) = 4.6 V, (4.8 V - 0.2 V).
As V(BAT) increases further, V(PACK) and the V(GS) voltage increase. But the VDS remains at 0.2 V because the
ZVCHG-FET is driven in its MOS linear region, point B.
V(PACK) = VF + 0.2 V + V(BAT)
where VF = 0.7 V is the forward voltage of a DSG-FET back diode and is typically 0.7 V
The R(ZVCHG) purpose is to split heat dissipation across the ZVCHG-FET and the resistor.
ZVCHG pin behavior is shown in Figure 9 where V(ZVCHG) is set to 0 V at the beginning.
24
bq29312
www.ti.com
SLUS546E – MARCH 2003 – REVISED MARCH 2005
APPLICATION INFORMATION (continued)
20
18
16
V(PACK)
14
Voltage - V
V(ZVCHG)=
V(PACK) - 8 V
V(BAT)
12
10
8
6
4
V(ZVCHG)= V(PACK) / 2
2
3.5 V
0
0
4
8
12
t - Time - mS
16
20
Figure 9. Voltage Transition at ZVCHG, PACK and BAT
As V(PACK) exceeds 7 V, V(ZVCHG) = V(PACK)/2. However, V(ZVCHG) is maintained to limit the voltage between PACK
and ZVCHG at a maximum of 8 V(typ). This limitation is intended to avoid excessive voltage between the gate
and the source of ZVCHG-FET.
The signal timing is shown in Figure 10. When precharge begins (V(BAT) = 0 V) V(PACK) is clamped to 3.5 V and
holds the supply voltage for bq29312 operation. After V(BAT) reaches sufficient voltage high enough for bq29312
operation, the CHG-FET and the DSG-FET are turned ON and ZVCHG-FET is turned OFF.
Although the current path is changed, the same precharging current is still applied. When V(BAT) reaches the fast
charging voltage (typical 3 V per cell), the charger switches into fast charging mode.
25
bq29312
www.ti.com
SLUS546E – MARCH 2003 – REVISED MARCH 2005
APPLICATION INFORMATION (continued)
V(PACK)
3.5 V+VGS(ZVCHGFET)
0V
3.3 V
0V
REG
ZVCHG FET = OFF
ON
V = VPACK*(1/2)
ZVCHG
3.5 V (typ.)
0V
OFF
CHG FET = ON
GHD
”L” (1 V)
OFF
CHG FET = ON
DSG
”L” (1 V)
Battery
Voltage
0V
Charge
Current
Fast Charge Current
0 V and Precharge Current
0A
0 V Charge
Mode
Precharge
Mode
Fast Charge Mode
Figure 10. Signal Timing of Pins During 0 V Charging and Precharging (0 V Charge FET)
Common FET
This mode does not require a dedicated precharge FET (ZVCHG-FET). The charge FET (CHG-FET) is ON at
initialization of the bq29312 when PMS = V(PACK) allowing for 0 V or precharge current to flow. The application
circuit is shown in Figure 11. The charger is expected to provide the precharge function in this mode, where the
charger provides a precharge current level suitable to charge cells below a set level, typically below 3.0 V per
cell. When the lowest cell voltage rises above this level then a fast charging current is applied.
When the charger is connected the voltage at PMS rises. Once it is above 0.7 V, the CHG output is driven to
GND which turns ON the CHG-FET. The charging current flows through the CHG-FET and a back diode of
DSG-FET. The pack voltage is represented by the following equation.
V(PACK) = V(BAT) + VF + VDS(CHG-FET)
Where VF = 0.7 V is the forward voltage of a DSG-FET back diode and is typically 0.7 V.
While V(PACK) is maintained above 0.7 V the precharging current is maintained. While V(PACK) and V(BAT) are
under the bq29312 supply voltage then the bq29312 regulator is inactive and the host controller is not functional.
Thus, any protection features of this chipset do not function during this period. This state continues until V(PACK)
goes higher than the bq29312 minimum supply voltage.
When V(BAT) rises and V(PACK) reaches bq29312 minimum supply voltage, the REG output is active providing a
3.3 V (typ) supply to the host. When this level is reached the CHG pin changes its state from GND to the level
controlled with CHG bit in bq29312 registers. In this state, the CHG output level is driven by a clamp circuit so
that its voltage level changes from 0 V to 1 V. Also, the host controller is active and can turn ON the DSG-FET.
26
bq29312
www.ti.com
SLUS546E – MARCH 2003 – REVISED MARCH 2005
APPLICATION INFORMATION (continued)
The disadvantages is that during 0 V charging, bq29312 is inactive. The device does not protect the battery and
does not update battery information (now is 0 V charging) to the PC.
There are two advantage of this configuration:
1. The voltage between BAT and PACK is lower. Higher precharge current is allowed due to less heat loss is
the FET and no external resistor required.
2. The charge FET is turned on during precharging. The precharge current can be fully controlled by the
charger.
Charger
CC
DC Input
I(ZVCHG)
DSG-FET
CHG-FET
DSG
BAT
CHG
PACK
bq29312
Battery
REG
OD
4.7 µF
NC
ZVCHG
Pack+
I(FASTCHG)
CV
PMS
I(ZVCHG) = 0 V Percharge Current
I(FASTCHG) = Fast Current
Figure 11. Common FET Mode Circuit Diagram
The signal timing during the common FET mode is shown in Figure 12. The CHG-FET is turned on when the
charger is connected. As V(BAT) rises and V(PACK) reaches the bq29312 minimum supply voltage, the REG output
becomes active and the host controller starts to work.
When V(PACK) becomes high enough, the host controller turns ON the DSG-FET. The charger enters the fast
charging mode when V(BAT) reaches the fast charge level.
27
bq29312
www.ti.com
SLUS546E – MARCH 2003 – REVISED MARCH 2005
APPLICATION INFORMATION (continued)
0.7 V
0V
V(PACK)
Host =
Inactive
Host = Active
REG
3.3 V
0V
PMS
CHG
Set to ”L” as
PMS = PACK
0V
Set to ”L” by Host
”L” (1 V)
0V
DSG
Host Sets
DSG-FET to ON
”L” (1 V)
Battery
Voltage
0V
Charge
Current
Fast Charge Current
0 V and Precharge Current
0A
0 V Precharge Mode
Fast Charge Mode
Figure 12. Signal Timing of Pins During 0 V Charging and Precharging (Common FET)
Precharge FET
This mode has a dedicated precharge current path using an additional open drain driven FET (PCHG-FET) and
sustains the V(PACK) level. In this mode, where the PMS input is connected to GND, the bq29312 and host
combine to provide the precharge function by limiting the fast charge current which is provided by the system
side charger.
Figure 13 shows the bq29312 application circuit in this mode.
28
bq29312
www.ti.com
SLUS546E – MARCH 2003 – REVISED MARCH 2005
APPLICATION INFORMATION (continued)
R(PCHG)
Charger
PCHG-FET
CC
DC Input
I(FASTCHG)
DSG-FET
CHG-FET
DSG
CHG
PACK
OD
BAT
CV
bq29312
Battery
Pack+
ZVCHG
PMS
REG
SCLK SDATA
4.7 µF
I(FASTCHG) = Fast Current
Host
Figure 13. Precharge FET Mode Circuit Diagram
The PCHG-FET is driven by the OD output and the resister R(PCHG) in the precharge path limits the precharge
current. When OD = GND then the PCHG-FET is ON. The precharge current is represented by the following
equation:
I(PCHG) = ID = ( V(PACK) - V(BAT) - VDS )/R(PCHG)
• A load curve of the PCHG-FET is shown in Figure 14. When the drain-source voltage (VDS) is high enough,
the PCHG-FET operates in the linear region and has low resistance. By approximating VDS as 0 V, the
precharge current, I(PCHG) is expressed as below.
• I(PCHG) = ( V(PACK) - V(BAT) )/R(PCHG)
ID
ID = (V(PACK) - V(BAT) - VDS)/R(PCHG)
VSD
Figure 14. PCHG-FET ID—VDS Characteristic
During the precharge phase, CHG-FET is turned OFF and PCHG-FET is turned ON. When all the cell voltages
measured by the host reach the fast charge threshold, the host controller turns ON CHG-FET and turns OFF
PCHG-FET. The signal timing is shown in Figure 15.
When the charger is connected, CHG-FET, DSG-FET and PCHG-FET are already in the OFF state. When the
charger in connected it applies V(PACK). The bq29312 REG output then becomes active and supplies power to the
host controller. As the host controller starts up, it turns on the OD pin and the precharge current is enabled.
29
bq29312
www.ti.com
SLUS546E – MARCH 2003 – REVISED MARCH 2005
APPLICATION INFORMATION (continued)
In this configuration, attention must be paid to high power consumption in the PCHG-FET and the series resistor
R(PCHG). The highest power is consumed when VBAT = 0 V, where it is the highest differential between the PACK
and BAT pins. For example, the power consumption in 4 series cells with 17.4 V fast charge voltage and R(PCHG)
= 188 Ω is expressed below.
• IPCHG = (17.4 V – 0.0 V)/188 Ω = 92.6 mA
• 17.4 V × 92.6 mA = 1.61 W
An optional solution is to combine a thermistor with a resistor to create R(PCHG), therefore, as temperature
increases, the current reduces.
Once the lowest cell voltage reaches the fast charge level (typ 3.0 V per cell), the host controller turns ON
CHG-FET and DSG-FET, and turns OFF PCHG-FET.
It is also appropriate to turn on DSG-FET during precharge in order to supply precharge current efficiently, as
shown in Figure 15.
Charge CV
V(PACK)
0V
Host : Active
REG
3.3 V
0V
OD
OFF
PCHG FET = ON
OFF
0V
CHG
CHG FET = OFF
”L” (1 V)
DSG FET = ON
DSG
OFF
”L” (1 V)
Battery
Voltage
Charge
Current
0V
Fast Charge Current
Charge
0 V and Precharge Current
0A
Charge Mode
0 V and
Precharge Mode
Fast Charge
Mode
Figure 15. Signal Timing of Pins During 0 V Charging and Precharging (Precharge FET)
30
bq29312
www.ti.com
SLUS546E – MARCH 2003 – REVISED MARCH 2005
APPLICATION INFORMATION (continued)
Summary
The three types of 0-V charge options available with the bq29312 are summarized in Table 4.
Table 4. Charge Options
CHARGE MODE TYPE
HOST CHARGE CAPABILITIES
KEY APPLICATION CIRCUIT NOTES
PMS = GND
1) 0-V Charge FET
Fast charge and precharge
ZVCHG: Drives 0-V charge FET (ZVCHG-FET)
OD: Not used
PMS = PACK
2) Common FET
Fast charge and precharge
ZVCHG: Not used
OD: Not used
PMS = GND
3) Precharge FET
Fast charge but no precharge function
ZVCHG: Not used
OD: Drives the precharge FET (PCHG-FET)
There a number of tradeoffs between the various 0-V charge modes which are discussed below.
• 0-V Charge FET (1) vs Common FET (2)
When the charger has both of precharge and charging functions, there are two types of circuit configuration
available.
1. 0-V Charge FET – The bq29312 is active even during precharge. Therefore, the host can update the battery
status to the system and protect the battery pack by detecting abnormal conditions.
– A high voltage is applied on the 0-V charge FET at 0-V cell voltage. In order to avoid excessive heat
generation the 0-V charge current must be limited.
2. Common FET – During 0-V charge the bq29312 and the host are not active. Therefore, they cannot protect
the cells and cannot update the battery status to the system.
– The bq29312 can tolerate high 0-V charge current as heat generation is not excessive.
– A dedicated FET for the 0-V charge is not required.
• 0-V Charge FET (1) vs Precharge FET (3)
The current paths of the 0-V charge FET (1) and Precharge FET (3) modes are the same. If the 0-V charge FET
(1) mode is used with chargers without precharge function, the bq29312 consumes extra current of up to 1 mA in
order to turn ON the ZVCHG output.
1. If the charger has a precharge function - ZVCHG-FET is turned ON only during 0-V charging. In this case, 1
mA increase is not a concern because the charger is connected during the 0-V charging period.
2. If the charger does not have precharge function - The ZVCHG-FET must be turned ON during 0-V charging
and also precharging. When the battery reaches an over discharged state, it must turn OFF DSG-FET and
CHG-FET and turn ON ZVCHG-FET. The reason for this is the battery must keep the 0-V charge path while
waiting for a charger to be connected to limit the current.
– Consuming 1 mA, while waiting for a charger to be connected in over discharge state, is significant if
compared to current consumption of other modes.
• Precharge FET (3)
If the precharge FET (3) mode is used with a charger with precharge function, care must be taken as limiting the
0-V charge current with resistance may cause some issues. The charger may start fast charge immediately, or
detect an abnormal condition.
When the charger is connected, the charger may raise the output voltage to force the precharge current. In order
to assure a supply voltage for the bq29312 during 0-V charging, the resistance of a series resister (RPCHG) must
be high enough. This may result in a very high VPACK, and some chargers may detect it as an abnormal
condition.
31
PACKAGE OPTION ADDENDUM
www.ti.com
11-Apr-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)
Top-Side Markings
(3)
(4)
BQ29312PW
NRND
TSSOP
PW
24
60
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
-25 to 85
29312PW
BQ29312PWG4
NRND
TSSOP
PW
24
60
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
-25 to 85
29312PW
BQ29312PWR
NRND
TSSOP
PW
24
2000
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
-25 to 85
29312PW
BQ29312PWRG4
NRND
TSSOP
PW
24
2000
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
-25 to 85
29312PW
BQ29312RGE
OBSOLETE
VQFN
RGE
24
TBD
Call TI
Call TI
(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)
Multiple Top-Side Markings will be inside parentheses. Only one Top-Side 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 Top-Side 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.
Addendum-Page 1
Samples
PACKAGE OPTION ADDENDUM
www.ti.com
11-Apr-2013
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 2
PACKAGE MATERIALS INFORMATION
www.ti.com
14-Jul-2012
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
BQ29312PWR
Package Package Pins
Type Drawing
TSSOP
PW
24
SPQ
Reel
Reel
A0
Diameter Width (mm)
(mm) W1 (mm)
2000
330.0
16.4
Pack Materials-Page 1
6.95
B0
(mm)
K0
(mm)
P1
(mm)
8.3
1.6
8.0
W
Pin1
(mm) Quadrant
16.0
Q1
PACKAGE MATERIALS INFORMATION
www.ti.com
14-Jul-2012
*All dimensions are nominal
Device
Package Type
Package Drawing
Pins
SPQ
Length (mm)
Width (mm)
Height (mm)
BQ29312PWR
TSSOP
PW
24
2000
367.0
367.0
38.0
Pack Materials-Page 2
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 © 2015, Texas Instruments Incorporated