Texas Instruments 3 Series Manual

High accuracy battery monitor and protector for li-ion, li-polymer, and lifepo4 battery packs
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BQ76952 3-Series to 16-Series High Accuracy Battery Monitor and Protector for

1 Features

Battery monitoring capability for 3-series to 16-
series cells
Integrated charge pump for high-side NFET
protection with optional autonomous recovery
Extensive protection suite including voltage,
temperature, current, and internal diagnostics
Two independent ADCs
– Support for simultaneous current and voltage
sampling
– High-accuracy coulomb counter with input
offset error < 1 µV (typical)
– High accuracy cell voltage measurement < 10
mV (typical)
Wide-range current applications (±200-mV
measurement range across sense resistor)
Integrated secondary chemical fuse drive
protection
Autonomous or host-controlled cell balancing
Multiple power modes (typical battery pack
operating range conditions)
– NORMAL mode: 286 µA
– Multiple SLEEP mode options: 24 µA to 41 µA
– Multiple DEEPSLEEP mode options: 9 µA to 10
µA
– SHUTDOWN mode: 1 µA
High-voltage tolerance of 85 V on cell connect and
select additional pins
Tolerant of random cell attach sequence on
production line
Support for temperature sensing using internal
sensor and up to nine external thermistors
Integrated one-time-programmable (OTP) memory
programmable by customers on production line
Communication options include 400-kHz I
and HDQ one-wire interface
Dual-programmable LDOs for external system
usage
48-pin TQFP package (PFB)
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
Copyright © 2021 Texas Instruments Incorporated
intellectual property matters and other important disclaimers. PRODUCTION DATA.
Li-Ion, Li-Polymer, and LiFePO
2
C, SPI,
Product Folder Links:
SLUSE13A – JANUARY 2020 – REVISED MAY 2021
SLUSE13A – JANUARY 2020 – REVISED MAY 2021
Battery Packs
4

2 Applications

Battery backup unit (BBU)
E-bike, e-scooter, and LEV
Cordless power tools and garden tools
Non-military drones
Other industrial battery pack (≥10S)

3 Description

The Texas Instruments BQ76952 device is a
highly integrated, high-accuracy battery monitor
and protector for 3-series to 16-series Li-ion, Li-
polymer, and LiFePO
4
includes a high-accuracy monitoring system, a
highly configurable protection subsystem, and support
for autonomous or host controlled cell balancing.
Integration includes high-side charge-pump NFET
drivers, dual programmable LDOs for external system
use, and a host communication peripheral supporting
2
400-kHz I
C, SPI, and HDQ one-wire standards.
The BQ76952 device is available in a 48-pin TQFP
package.
Device Information
(1)
PART NUMBER
PACKAGE
BQ76952xx
PFB (48-pin)
(1)
See the
Device Comparison Table
device family. For all available devices, see the orderable
addendum at the end of the data sheet.
+
VC15
+
VC14
+
+
VC13
VC12
+
+
VC11
VC10
+
+
VC9
+
VC8
+
VC7
+
VC6
+
VC5
VC4
+
+
+
+
Simplified Schematic
BQ76952
BQ76952
BQ76952
battery packs. The device
BODY SIZE (NOM)
7 mm × 7 mm
for information on the
PACK+
CHG
DSG
CAN
5V
COMM TO
TRANSCEIVER
SYSTEM
COMM
REGIN
REG1
REG2
VDD
3.3V
RST_SHUT
DDSG
MCU
DCHG
DFETOFF
CFETOFF
HDQ
SDA
SCL
ALERT
GND
PACK-
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1

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Summary of Contents for Texas Instruments 3 Series

  • Page 1: Features

    Other industrial battery pack (≥10S) temperature, current, and internal diagnostics 3 Description • Two independent ADCs The Texas Instruments BQ76952 device is a – Support for simultaneous current and voltage highly integrated, high-accuracy battery monitor sampling and protector for 3-series to 16-series Li-ion, Li- –...
  • Page 2: Table Of Contents

    19.1 Documentation Support.......... 10.3 Coulomb Counter and Digital Filters....... 19.2 Support Resources..........10.4 Synchronized Voltage and Current Measurement.. 19.3 Trademarks............. 10.5 Internal Temperature Measurement......38 19.4 Electrostatic Discharge Caution......79 Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 3: Revision History

    ......................... • Updated SPI Communications .........................56 • Updated SPI Protocol ............................• Updated HDQ Communications ........................• Updated Application and Implementation ......................• Updated Documentation Support ........................Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ76952...
  • Page 4: Device Comparison Table

    VC13 current input for the thirteenth cell from the bottom of the stack, and return balance current for the fourteenth cell from the bottom of the stack Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 5 Multifunction pin, can be ALERT output, or HDQ I/O, or thermistor input, or general ALERT I/OD, I/OA purpose ADC input, or general purpose digital output I/OD Multifunction pin, can be SCL or SPI_SCLK Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ76952...
  • Page 6 Sense voltage input pin for the sixteenth cell from the bottom of the stack, balance VC16 current input for the sixteenth cell from the bottom of the stack, and top-of-stack measurement point Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 7: Specifications

    Input voltage range, V VSS-0.3 and VSS+85 VC8–0.3 maximum of Input voltage range, V VSS-0.3 and VSS+85 VC7–0.3 maximum of Input voltage range, V VSS-0.3 and VSS+85 VC6–0.3 Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ76952...
  • Page 8: Esd Ratings

    JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process. JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process. Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 9: Recommended Operating Conditions

    CHG, DSG, CP1 Operating temperature –40 °C Cell voltage measurement 2 V < V < 5 V, T VC(x) VC(x-1) –5 CELL(ACC) accuracy 25°C, 1 ≤ x ≤ 16 Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ76952...
  • Page 10: Thermal Information Bq76952

    Periodic protections and monitoring, no pack current, REG1 = OFF, REG2 = OFF, CHG SLEEP Mode = OFF, DSG = source follower mode, no µA SLEEP_2 communication, Power:Sleep:Voltage Time = 5 Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 11: Digital I/O

    5.5 V or 11 V mode), the maximum voltage on V should be reduced to ensure the voltage on CP1, CHG, and DSG does not exceed their maximum specified voltage. Specified by design Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ76952...
  • Page 12: Ld Pin

    = 59.2 V, min/max values stated where T = -40°C to 85°C and V = 4.7 V to 80 V (unless otherwise noted) PARAMETER TEST CONDITIONS UNIT External capacitor, REG18 to VSS µF REG18 Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 13: Reg0 Pre-Regulator

    = 0 mA to 45 mA 3.36 REG1_3.3 REGIN REG1 Regulator voltage (nominal 5.0V setting) ≥ 5.0 V, I = 0 mA to 45 mA 5.19 REG1_5.0 REGIN REG1 Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ76952...
  • Page 14: Reg2 Ldo

    PPM/°C (REF1DRIFT) VOLTAGE REFERENCE 2 Internal reference voltage = 25°C 1.23 1.24 1.25 (REF2) (3) (4) Internal reference voltage drift = -10°C to 60°C ±20 PPM/°C (REF2DRIFT) Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 15: Coulomb Counter

    Code stability is defined as the resolution such that the data exhibits 3-sigma variation within ±1-LSB. Specified by a combination of design and production test Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links:...
  • Page 16: Current Measurement Digital Filter (Cc2)

    Input voltage range applicable to external thermistor (external thermistor measurements using the TS1, TS2, TS3, –0.2 (ADC_IN_TS) REG18 measurement mode) ALERT, CFETOFF, DFETOFF, HDQ, DCHG, and DDSG pins Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 17 CP1, CHG, and DSG does not exceed their maximum specified voltage. Code stability is defined as the resolution such that the data exhibits 3-sigma variation within ±1-LSB. Specified by design Specified by characterization Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ76952...
  • Page 18: Cell Balancing

    80 V (unless otherwise noted) PARAMETER TEST CONDITIONS UNIT Setting for nominal 18-kΩ 14.4 18.3 21.6 kΩ Internal pullup (TS_PU) resistance Setting for nominal 180-kΩ kΩ Internal pad Ω (TS_PAD) resistance Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 19: Internal Oscillators

    CP1, CHG, and DSG does not exceed their maximum specified voltage. Specified by design Specified by a combination of design and production test Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ76952...
  • Page 20: High-Side Nfet Drivers

    A larger value may be desired to avoid an overly GATE fast FET turn off, which can result in a large voltage transient due to cell and harness inductance. Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 21: Comparator-Based Protection Subsystem

    Short circuit in discharge voltage Nominal settings, threshold based on 175, – (SCD) threshold range 200, – 250, – 300, – 350, – 400, – 450, – Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ76952...
  • Page 22: Timing Requirements - I

    Data hold time (SDA input) HD:DAT Data setup time (SDA input) SU:DAT Clock rise time 10% to 90% 1000 Clock fall time 90% to 10% Setup time STOP condition µs SU:STO Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 23: Timing Requirements - I C Interface, 400Khz Mode

    CYCH Cycle Time, device to Host Device drives HDQ µs CYCD Device Write 1 Time Device drives HDQ µs Device Write 0 Time Device drives HDQ µs Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ76952...
  • Page 24: Timing Requirements - Spi Interface

    CP1, CHG, and DSG does not exceed their maximum specified voltage. Specified by design See later discussion in datasheet for more details Specified by characterization Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 25: Interface Timing Diagrams

    L S B O U T SPI_MISO t SU t HI SPI_MOSI « %,7 M S B IN L S B IN Figure 7-2. SPI Communications Interface Timing Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ76952...
  • Page 26 HDQ Host to Device communication d. Device to HDQ Host communication e. Device to HDQ Host response format f. HDQ Host to Device Figure 7-3. HDQ Communications Interface Timing Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 27: Typical Characteristics

    Figure 7-6. Cell Voltage Measurement Error vs. Figure 7-7. Cell Voltage Measurement Error vs. Temperature with Cell Voltage = 2.5 V Temperature with Cell Voltage = 3.5 V Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ76952...
  • Page 28 Error in measurement of differential voltage between SRP and SRN pins Figure 7-11. Internal Voltage References vs. SRN pins Temperature (VREF1 and VREF2) Figure 7-10. Current Measurement Error vs. Temperature Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 29 Figure 7-15. Overcurrent in Discharge Protection 1 Accuracy vs. Temperature (OCD1) Threshold vs. Temperature Figure 7-16. Overcurrent in Charge Protection Figure 7-17. Cell Balancing Resistance vs. (OCC) Threshold vs. Temperature Temperature Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ76952...
  • Page 30 Figure 7-22. Thermistor Pullup Resistance vs. Error calculated as percentage of nominal gain across ±200- Temperature (180-kΩ Setting) mV input range Figure 7-23. Coulomb Counter Gain Error vs. Temperature Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 31 Measurements taken using external BJT Figure 7-27. REGIN Voltage vs. BAT Voltage Figure 7-28. BAT Current in NORMAL Mode vs. Figure 7-29. BAT Current in SHUTDOWN Mode vs. Temperature Temperature Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ76952...
  • Page 32 SLUSE13A – JANUARY 2020 – REVISED MAY 2021 Figure 7-30. BAT Current in SLEEP2 (SRC Figure 7-31. BAT Current in DEEPSLEEP2 (No Follower) Mode vs. Temperature LFO) Mode vs. Temperature Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 33: Device Description

    NFET. Three dedicated pins enable temperature measurements using external thermistors, and multifunction pins can be programmed to use for additional thermistors, supporting a total of up to nine thermistors, in addition to an internal die temperature measurement. Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links:...
  • Page 34: Functional Block Diagram

    LFO frequency, memory checks at power-up or reset, an internal watchdog on the embedded processor, and more. The BQ76952 Technical Reference Manual describes these in detail. Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 35: Device Configuration

    The scratchpad data can be written into OTP memory on the customer production line. This data can only be written while in FULLACCESS mode, although it can be read in all modes. Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links:...
  • Page 36: Measurement Subsystem

    –0.2 V. Therefore, it is important that the I·R voltage drop across the interconnect resistance does not cause a violation of this requirement. Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 37: General Purpose Adcin Functionality

    This includes the TS1, TS2, TS3, CFETOFF, DFETOFF, HDQ, DCHG, DDSG, and ALERT pins. When used for ADCIN functionality, the internal bandgap reference is Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback...
  • Page 38: Coulomb Counter And Digital Filters

    (delta-V ). This voltage is measured periodically as part of the measurement loop and is processed to provide a reported temperature value available through the digital Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 39: Thermistor Temperature Measurement

    The resulting reported data does not include any further correction (such as for gain), therefore the customer will need to process them before use. Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links:...
  • Page 40: Voltage Calibration (Adc Measurements)

    CUV (cell undervoltage) protection thresholds on the production line, in order to improve threshold accuracy in system or to realize a threshold between the preset thresholds available from the device. Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 41: Current Calibration

    HDQ Temp Offset HDQ pin thermistor 0.1 K Calibration Temperature DCHG Temp Offset DCHG pin thermistor 0.1 K Calibration Temperature DDSG Temp Offset DDSG pin thermistor 0.1 K Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ76952...
  • Page 42: Primary And Secondary Protection Subsystems

    Undertemperature in Discharge Protection • Internal Undertemperature Protection • Overtemperature in Charge Protection • Overtemperature in Discharge Protection • Internal Overtemperature Protection • FET Overtemperature Protection • Precharge Timeout Protection Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 43: Secondary Protections

    Voltage Imbalance at Rest Permanent Fail • Second Level Protector Permanent Fail • Discharge FET Permanent Fail • Charge FET Permanent Fail • OTP Memory Permanent Fail Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ76952...
  • Page 44: High-Side Nfet Drivers

    BQ76952 will reenable the FETs if nothing is blocking them being reenabled (such as fault conditions still present, or the CFETOFF or DFETOFF pins are asserted). Manual control Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 45: Protection Fets Configuration And Control

    LD pin above a 4-V level, then the device can recover from the fault. Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback...
  • Page 46: Device Hardware Features

    There is a diode connection between the REGIN pin (anode) and the BAT pin (cathode), so the voltage on REGIN should not exceed the voltage on BAT. Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 47: Standalone Versus Host Interface

    Input to control the CHG FET (that is, CFETOFF functionality) DFETOFF Input to control the DSG FET (that is, DFETOFF functionality) Input to control both the DSG and CHG FETs (that is, BOTHOFF functionality) HDQ communications Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ76952...
  • Page 48: Rst_Shut Pin Operation

    ADC input, a general purpose digital output, or an HDQ serial communication interface. The pin can be configured as active-high, active-low, or open-drain, to Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 49: Ddsg And Dchg Pin Operation

    FETs and the PACK+ connector, then the device bases its decision on the PACK pin voltage (based on configuration setting). This voltage threshold check may be disregarded under certain special cases, as described in the BQ76952 Technical Reference Manual (SLUUBY2) Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ76952...
  • Page 50: Cell Open Wire

    The high frequency oscillator (HFO) in the BQ76952 device operates at 16.78 MHz and is frequency locked to the LFO. The HFO powers up as needed for internal logic functions. Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 51: Device Functional Modes

    System current is measured at intervals of 3 ms, with cell voltages measured at intervals of 63 ms or slower, depending on configuration. The device also provides a configuration Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback...
  • Page 52: Sleep Mode

    NORMAL mode. This may take ≈250 ms plus the time for the measurement loop to complete. Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 53: Shutdown Mode

    120°C. If this detector triggers, the device will automatically begin the sequence to enter SHUTDOWN if this functionality is enabled through configuration. Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links:...
  • Page 54: Config_Update Mode

    In a block write transaction, the CRC for the first data byte is calculated over the responder address, register address, and data. The CRC for subsequent data bytes is calculated over the data byte only. Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 55 + x + 1, and the initial value is 0. When the controller detects an invalid CRC, the I C controller will NACK the CRC, which causes the I responder to go to an idle state. Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ76952...
  • Page 56: Spi Communications

    If the host performs a write with CRC and the CRC is not correct, then the incoming data is not transferred to the incoming buffer, and the outgoing buffer (used for the next transaction) is also reset to 0xFFFF. This transaction Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 57 0xFFFF; and if the CRC is clocked, it will clock out 0x00 for the CRC (if enabled). Thus, the 0xFFFF00 command indicates to the controller that the outgoing buffer Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback...
  • Page 58 SPI_MISO Previous R/W bit Previous 8-bit 8-bit CRC & 7-bit address write or read data (for previous two bytes) Figure 14-5. SPI Transaction #1 Using CRC Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 59 R/W bit & 7-bit 8-bit write or 8-bit CRC address # 2 read data # 2 (for previous two bytes) Figure 14-7. SPI Transaction #3 Using CRC Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ76952...
  • Page 60 8-bit write address # 1 data # 1 SPI_MISO Previous R/W bit Previous 8-bit & 7-bit address write or read data Figure 14-8. SPI Transaction #1 Without CRC Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 61 # 2 (or don’t care if read) SPI_MISO R/W bit & 7-bit 8-bit write address # 1 data # 1 Figure 14-9. SPI Transaction #2 Without CRC Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ76952...
  • Page 62: Hdq Communications

    The BQ76952 device can be changed from the default communication mode to HDQ communication mode by setting the Settings:Configuration:Comm Type configuration register or by sending a subcommand (at which point the device switches to HDQ mode immediately). Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 63: Cell Balancing

    ADC, as well as when the cells immediately adjacent to the active cell are being measured. Similarly, balancing on the top cell is disabled while the stack voltage measurement is underway. Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback...
  • Page 64: Application And Implementation

    The diode in the BAT connection and the diode in the BJT collector should not be shared, since then the REG0 circuit might discharge the capacitor on BAT too quickly during a short circuit event. Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 65 400 nF, then changing CP1 to a value of 2200 nF will result in the 11-V charge pump level dropping to approximately 9 V, before being restored to the 11-V level by the charge pump. Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback...
  • Page 66 A full schematic of a basic monitor circuit based on the BQ76952 for a 16-series battery pack is shown below. Section 18.2 shows the board layout for this design. Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 67 PGND TP19 0.1uF PGND 5.1k 7.50k TP20 5.1k PACK TP21 TP22 PGND TP23 100V PACK 5.1k 5.1k 5.1k 5.1k Figure 16-3. BQ76952 16-Series Cell Schematic Diagram—Additional Circuitry Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ76952...
  • Page 68 Use as ALERT interrupt pin, polarity = driven low when active, hi-Z otherwise REG1 LDO Usage Use for 3.3-V output Cell balancing Enabled when imbalance exceeds 100 mV 16.2.2 Detailed Design Procedure • Determine the number of series cells. Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 69 16.2.3 Application Performance Plot The error in measured temperature using an external Semitec 103-AT thermistor, the default temperature polynomial, and the internal 18-kΩ pullup resistor is shown in Figure 16-4. Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ76952...
  • Page 70: Random Cell Connection Support

    This means an upper cell input pin should not be driven to a low voltage while a lower cell input pin is driven to a higher voltage, since this would forward bias these diodes. During cell attach, the cell input terminals Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 71: Startup Timing

    [FASTADC] = 1, [FET_EN] = 1 for autonomous FET control, setup to use three thermistors, and providing the [INITCOMP] flag on the ALERT pin. The TS2 pin is pulled low to initiate device wakeup from SHUTDOWN. Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback...
  • Page 72: Fet Driver Turn-Off

    DSG pin and the FET gate, and a light load on PACK+, such that the voltage on PACK+ drops slowly as the FET is disabled. The pulsing on the DSG pin can be seen lasting for approximately 170 μs. Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 73 Figure 16-7. Zoomed-In View of the Pulsing on the DSG Pin During FET Turn-Off A slower turn-off case is shown in Figure 16-8, using a 4.7 kΩ series gate resistor, and the PACK+ connector shorted to the top of stack. Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ76952...
  • Page 74: Unused Pins

    16.6 Unused Pins Some device pins may not be needed in a particular application. The manner in which each should be terminated in this case is described below. Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 75: Power Supply Requirements

    50 ppm in order to minimize current measurement drift with temperature. Choose the value of the sense resistor to correspond to the available overcurrent and short- Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback...
  • Page 76: Layout Example

    The board layout, which is shown in Figure 18-1 Figure 18-2, includes spark gaps with the reference designator prefix E. These spark gaps are fabricated with the board and no component is installed. Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 77 BQ76952 www.ti.com SLUSE13A – JANUARY 2020 – REVISED MAY 2021 Figure 18-1. BQ76952 Two-Layer Board Layout–Top Layer Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ76952...
  • Page 78 BQ76952 www.ti.com SLUSE13A – JANUARY 2020 – REVISED MAY 2021 Figure 18-2. BQ76952 Two-Layer Board Layout–Bottom Layer Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ76952...
  • Page 79: Documentation Support

    All trademarks are the property of their respective owners. 19.4 Electrostatic Discharge Caution This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.
  • Page 80 PACKAGE OPTION ADDENDUM www.ti.com 8-May-2021 PACKAGING INFORMATION Orderable Device Status Package Type Package Pins Package Eco Plan Lead finish/ MSL Peak Temp Op Temp (°C) Device Marking Samples Drawing Ball material (4/5) BQ7695201PFBR ACTIVE TQFP 1000 RoHS & Green Call TI Call TI -40 to 85 BQ7695201...
  • Page 81 PACKAGE OPTION ADDENDUM www.ti.com 8-May-2021 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.
  • Page 82 PACKAGE MATERIALS INFORMATION www.ti.com 16-Apr-2021 TAPE AND REEL INFORMATION *All dimensions are nominal Device Package Package Pins Reel Reel Pin1 Type Drawing Diameter Width (mm) (mm) (mm) (mm) (mm) Quadrant (mm) W1 (mm) BQ7695201PFBR TQFP 1000 330.0 16.4 12.0 16.0 BQ7695202PFBR TQFP 1000...
  • Page 83 PACKAGE MATERIALS INFORMATION www.ti.com 16-Apr-2021 *All dimensions are nominal Device Package Type Package Drawing Pins Length (mm) Width (mm) Height (mm) BQ7695201PFBR TQFP 1000 336.6 336.6 31.8 BQ7695202PFBR TQFP 1000 336.6 336.6 31.8 BQ7695204PFBR TQFP 1000 336.6 336.6 31.8 BQ76952PFBR TQFP 1000 336.6...
  • Page 84 MECHANICAL DATA MTQF019A – JANUARY 1995 – REVISED JANUARY 1998 PFB (S-PQFP-G48) PLASTIC QUAD FLATPACK 0,27 0,50 0,08 0,17 0,13 NOM 5,50 TYP 7,20 Gage Plane 6,80 9,20 8,80 0,25 0,05 MIN 0 – 7 1,05 0,95 0,75 Seating Plane 0,45 0,08 1,20 MAX...
  • Page 86 TI products. TI’s provision of these resources does not expand or otherwise alter TI’s applicable warranties or warranty disclaimers for TI products.IMPORTANT NOTICE Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265 Copyright © 2021, Texas Instruments Incorporated...
  • Page 87 Mouser Electronics Authorized Distributor Click to View Pricing, Inventory, Delivery & Lifecycle Information: Texas Instruments BQ7695204PFBR...

This manual is also suitable for:

16 seriesBq76952Bq7695201Bq7695202Bq7695203Bq7695204

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