Texas Instruments BQ769142 Manual

Texas Instruments BQ769142 Manual

High accuracy battery monitor and protector for liion, li-polymer, and lifepo4 battery packs
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BQ769142 3-Series to 14-Series High Accuracy Battery Monitor and Protector for Li-

1 Features

Battery monitoring capability for 3-series to 14-
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.
Ion, Li-Polymer, and LiFePO
2
C, SPI,
Product Folder Links:
SLUSE91A – SEPTEMBER 2020 – REVISED FEBRUARY 2021
SLUSE91A – SEPTEMBER 2020 – REVISED FEBRUARY 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 BQ769142 device is a highly
integrated,
high-accuracy
protector for 3-series to 14-series Li-ion, Li-polymer,
and LiFePO
battery packs. The device includes a
4
high-accuracy
monitoring
configurable protection subsystem, and support for
autonomous
or
host
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
BQ769142 device is available in a 48-pin TQFP
package.
Device Information
(1)
PART NUMBER
PACKAGE
BQ769142xx
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.
+
VC13A
VC13B
+
VC12A
VC12B
+
VC11
+
VC10
+
VC9
+
VC8
+
+
VC7
+
VC6
VC5
+
VC4
+
+
+
+
Simplified Schematic
BQ769142
BQ769142
BQ769142
battery
monitor
system,
a
highly
controlled
cell
balancing.
BODY SIZE (NOM)
7 mm × 7 mm
for information on the
PACK+
CHG
DSG
CAN
5V
COMM TO
TRANSCEIVER
COMM
REGIN
REG1
REG2
VDD
3.3V
RST_SHUT
DDSG
MCU
DCHG
DFETOFF
CFETOFF
HDQ
SDA
SCL
ALERT
GND
PACK-
Submit Document Feedback
and
SYSTEM
1

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Summary of Contents for Texas Instruments BQ769142

  • Page 1: Features

    BQ769142 www.ti.com SLUSE91A – SEPTEMBER 2020 – REVISED FEBRUARY 2021 SLUSE91A – SEPTEMBER 2020 – REVISED FEBRUARY 2021 BQ769142 3-Series to 14-Series High Accuracy Battery Monitor and Protector for Li- Ion, Li-Polymer, and LiFePO Battery Packs 1 Features 2 Applications •...
  • Page 2: Table Of Contents

    19.1 Third-Party Products Disclaimer......10.3 Coulomb Counter and Digital Filters....... 19.2 Documentation Support.......... 10.4 Synchronized Voltage and Current Measurement.. 19.3 Support Resources..........10.5 Internal Temperature Measurement......36 19.4 Trademarks............. Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ769142...
  • Page 3: Revision History

    Changes from Revision * (December 2020) to Revision A (February 2021) Page • Updated the short circuit in discharge voltage threshold detection accuracy characteristics in the Comparator- Based Protection Subsystem section (page 21) of the Specifications ...............7 Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ769142...
  • Page 4: Device Comparison Table

    VC10 DCHG DFETOFF CFETOFF ALERT Not to scale Table 6-1. BQ769142 TQFP Package (PFB) Pin Functions TYPE DESCRIPTION NAME Return balance current for the fourteenth cell from bottom of the stack. This pin VC13A should be shorted to VC13B on the PCB.
  • Page 5 BQ769142 www.ti.com SLUSE91A – SEPTEMBER 2020 – REVISED FEBRUARY 2021 Table 6-1. BQ769142 TQFP Package (PFB) Pin Functions (continued) TYPE DESCRIPTION NAME Sense voltage input pin for the ninth cell from the bottom of the stack, balance current input for the ninth cell from the bottom of the stack, and return balance current for the...
  • Page 6 BQ769142 www.ti.com SLUSE91A – SEPTEMBER 2020 – REVISED FEBRUARY 2021 Table 6-1. BQ769142 TQFP Package (PFB) Pin Functions (continued) TYPE DESCRIPTION NAME Multifunction pin, can be DCHG, thermistor input, general purpose ADC input, or DCHG OD, I/OA general purpose digital output...
  • 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: BQ769142...
  • 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: BQ769142...
  • 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 ≤ 14 Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ769142...
  • Page 10: Thermal Information Bq769142

    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: BQ769142...
  • 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: BQ769142...
  • Page 12: Ld Pin

    = -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 Regulator voltage REG18 Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ769142...
  • Page 13: Reg0 Pre-Regulator

    25°C, I = 20 REG1 REG1 REG1 ΔV Regulator output over temperature mA, V = 5.5 V, V set to ±0.25 O(TEMP) REGIN REG1 nominal 3.3 V setting) Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ769142...
  • Page 14: Reg2 Ldo

    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. Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ769142...
  • Page 15: Coulomb Counter

    Single conversion, in NORMAL mode, Conversion-time Settings:Configuration:Power 2.93 (CC2_CONV) Config[FASTADC] = 0 Single conversion, in NORMAL mode, Conversion-time in fast mode Settings:Configuration:Power 1.46 (CC2_CONV_FAST) Config[FASTADC] = 1 Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ769142...
  • Page 16: Current Wake Detector

    16-bit, best fit over -0.1 V to 5.5 V –6.6 (when using V REF1 and differential cell (ADC_INL) voltage measurement 16-bit, best fit over -0.2 V to 0.2 V –4 mode at VC14 - VC13A) Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ769142...
  • Page 17 REF1 Average effective differential input resistance with device operating in NORMAL mode, cell balancing disabled, three or more thermistors in use, and a 5 V differential voltage applied. Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links:...
  • Page 18: Cell Balancing

    The internal pad resistance includes the resistance between the point where the voltage is sensed by the ADC and the pin where an external thermistor is attached (which includes the TS1, TS2, TS3, ALERT, CFETOFF, DFETOFF, HDQ, DCHG, and DDSG pins) Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ769142...
  • Page 19: Internal Oscillators

    BAT, DSG pin voltage with CHG/DSG C = 20 nF, charge pump low (FETON_LO) respect to BAT, 8 V ≤ overdrive setting ≤ 80 V, V ≤ Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ769142...
  • Page 20: Comparator-Based Protection Subsystem

    3.036 V and 5.06 V = -40°C to +85°C, nominal setting ±5 between 1.012 V and 5.566 V = -40°C to +85°C, nominal setting –25 between 3.036 V and 5.06 V Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ769142...
  • Page 21 Nominal setting (15 µs steps) µs 15 µs steps 4 mV to Overcurrent in charge (OCC) voltage Nominal settings, threshold based on 124 mV (OCC) threshold range in 2 mV steps Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ769142...
  • Page 22: Interface, 100Khz

    = 4.7 V to 80 V (unless otherwise noted) PARAMETER TEST CONDITIONS UNIT Clock operating frequency SCL duty cycle = 50% START condition hold time µs HD:STA Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ769142...
  • Page 23: Timing Requirements - Hdq Interface

    CP1, CHG, and DSG does not exceed their maximum specified voltage. Specified by design Specified by characterization Response time will vary depending on the internal device processing Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ769142...
  • Page 24: Timing Requirements - Spi Interface

    When SPI pin filtering is enabled, pulses on input pins of duration below 200 ns may be filtered out. 7.31 Interface Timing Diagrams HD;STA SU;STA HD;STA SU;STO HIGH SU;DAT HD;DAT STOP START START REPEATED START Figure 7-1. I C Communications Interface Timing Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ769142...
  • Page 25 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 Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ769142...
  • Page 26: Typical Characteristics

    Figure 7-8. Cell Voltage Measurement Error vs. Figure 7-9. Cell Voltage Measurement Error vs. Temperature with Cell Voltage = 4.5 V Temperature with Cell Voltage = 5.5 V Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ769142...
  • Page 27 Figure 7-12. Internal Temperature Sensor (Delta LFO measured in full speed mode (262 kHz) ) Voltage vs. Temperature Figure 7-13. Low Frequency Oscillator (LFO) Accuracy vs. Temperature Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ769142...
  • Page 28 The top of the string is swept and captured as the Cell Voltage. Figure 7-18. Cell Balancing Resistance vs. Cell Common-mode Voltage at 25°C Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ769142...
  • Page 29 Temperature (180-kΩ setting) Figure 7-23. Coulomb Counter Gain Error vs. Temperature Figure 7-24. LD Wake Voltage vs. Temperature Figure 7-25. REG18 Voltage vs. Temperature, with No Load Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ769142...
  • Page 30 Figure 7-29. BAT Current in SHUTDOWN Mode vs. Temperature Temperature 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: BQ769142...
  • Page 31: Device Description

    SLUSE91A – SEPTEMBER 2020 – REVISED FEBRUARY 2021 8 Device Description 8.1 Overview The BQ769142 device is a highly integrated, accurate battery monitor and protector for 3-series to 14-series Li- ion, Li-polymer, and LiFePO battery packs. A high accuracy voltage, current, and temperature measurement accuracy provides data for host-based algorithms and control.
  • Page 32: Functional Block Diagram

    OCD2, OCC 8.4 Diagnostics The BQ769142 device includes a suite of diagnostic tests the system can use to increase operational robustness. These tests include comparisons between the two voltage references integrated within the device, a hardware monitor of the LFO frequency, memory checks at power-up or reset, an internal watchdog on the embedded processor, and more.
  • Page 33: Device Configuration

    Manual. 9.2 Configuration Using OTP or Registers The BQ769142 device includes registers with values that are stored in the RAM and can be loaded automatically from one-time programmable (OTP) memory. At initial power-up, the device loads OTP settings into registers that are used by the device firmware during operation.
  • Page 34: Measurement Subsystem

    10.1.2 Using VC Pins for Cells Versus Interconnect If the BQ769142 device is used in a system with fewer than 14-series cells, the additional cell inputs can be utilized to improve measurement performance. For example, a long connection may exist between two cells in a...
  • Page 35: General Purpose Adcin Functionality

    32-bit format (in units of raw ADC counts), irrespective of whether they are used for cells or not. 10.2 General Purpose ADCIN Functionality Several multifunction pins on the BQ769142 device can be used for general purpose ADC input (ADCIN) measurement, if not being used for other purposes. This includes the TS1, TS2, TS3, CFETOFF, DFETOFF, HDQ, DCHG, DDSG, and ALERT pins.
  • Page 36: Coulomb Counter And Digital Filters

    ADC is effectively 1.6667 × VREF1, which is approximately 2.08 V during normal operation. The BQ769142 device also reports the raw ADC counts when a measurement is taken using the TS1 pin. This data can be used during manufacturing to better calibrate the ADCIN functionality.
  • Page 37: Thermistor Temperature Measurement

    SLUSE91A – SEPTEMBER 2020 – REVISED FEBRUARY 2021 10.6 Thermistor Temperature Measurement The BQ769142 device includes an on-chip temperature measurement and can also support up to nine external thermistors on multifunction pins (TS1, TS2, TS3, CFETOFF, DFETOFF, ALERT, HDQ, DCHG, and DDSG). The device includes an internal pullup resistor to bias a thermistor during measurement.
  • Page 38: Voltage Calibration (Adc Measurements)

    ADCIN measurement gain in Calibration:Voltage:ADC Gain. If values for the calibration gain configuration are not written, the BQ769142 device uses a factory trim or default values for the respective gain values. When a calibration gain configuration value is written, the device will use that in place of any factory trim or default gain.
  • Page 39: Current Calibration

    CUV threshold. Next, while in CONFIG_UPDATE mode, the CAL_CUV() subcommand is sent by the host, which causes the BQ769142 device to perform a search for the appropriate calibration coefficients to realize a CUV threshold at or close to the applied voltage level. When this search is completed, the resulting calibration coefficient is returned by the subcommand and automatically written into the Protections:CUV:CUV Threshold Override configuration parameter.
  • Page 40: Primary And Secondary Protection Subsystems

    When a Permanent Fail has occurred, the BQ769142 device can be configured to either simply provide a flag, or to indefinitely disable the protection FETs, or to assert the FUSE pin to permanently disable the pack. The FUSE pin can be used to blow an in-line fuse and also can monitor if a separate secondary protector IC has attempted to blow the fuse.
  • Page 41: Secondary Protections

    Host Watchdog Fault Protection 11.3 Secondary Protections The BQ769142 device integrates a suite of secondary protection checks on battery operation and status that can trigger a Permanent Fail (PF) if conditions are considered so serious that the pack should be permanently disabled.
  • Page 42: High-Side Nfet Drivers

    The BQ769142 device supports a system with FETs in a series or parallel configuration, where the parallel configuration includes a separate path for the charger connection versus the discharge (load) connection. The control logic for the device operates slightly differently in these two cases, which is set based on the configuration setting.
  • Page 43: Protection Fets Configuration And Control

    FETs. When a series FET configuration is used, the BQ769142 device provides body diode protection for the case when one FET is off and one FET is on.
  • Page 44: Device Hardware Features

    12.3.2 REG1 and REG2 LDO Controls The REG1 and REG2 LDOs in the BQ769142 device are for customer use, and their output voltages can be programmed independently to 1.8 V, 2.5 V, 3.0 V, 3.3 V, or 5.0 V. The REG1 and REG2 LDOs and the REG0 preregulator are disabled by default in the BQ769142 device.
  • Page 45: Standalone Versus Host Interface

    FETs. The host processor can interface with the BQ769142 device through a serial bus, as well as selected pin controls. Serial bus communication through I...
  • Page 46: Rst_Shut Pin Operation

    Pin can be used for general purpose ADC measurement. 12.6 RST_SHUT Pin Operation The RST_SHUT pin provides a simple way to reset or shutdown the BQ769142 device without needing to use serial bus communication. During normal operation, the RST_SHUT pin should be driven low. When the pin is driven high, the device will immediately reset most of the digital logic, including that associated with the serial communications bus.
  • Page 47: Ddsg And Dchg Pin Operation

    12.10 Fuse Drive The FUSE pin on the BQ769142 device can be used to blow a chemical fuse in the presence of a Permanent Fail (PF), as well as to determine if an external secondary protector in the system has detected a fault and is attempting to blow the fuse itself.
  • Page 48: Cell Open Wire

    12.11 Cell Open Wire The BQ769142 device supports detection of a broken connection between a cell in the pack and the cell attachment to the PCB containing BQ769142. Without this check, the voltage at the cell input pin of the BQ769142 device may persist for some time on the board-level capacitor, leading to incorrect voltage readings.
  • Page 49: Normal Mode

    SLEEP mode. The BQ769142 device exits SLEEP mode if a protection fault occurs, if current begins flowing, if a charger is attached, if forced by a subcommand, or if the RST_SHUT pin is asserted for less than 1 second. When exiting Copyright ©...
  • Page 50: Deepsleep Mode

    13.4 DEEPSLEEP Mode The BQ769142 device integrates a DEEPSLEEP mode, which is a low power mode that allows the REG1 and REG2 LDOs to remain powered, but disables other subsystems. In this mode, the protection FETs are all disabled, so no voltage is provided at the battery pack terminals.
  • Page 51: Config_Update Mode

    While the BQ769142 device is in NORMAL mode or SLEEP mode, the device can also be configured to enter SHUTDOWN mode if the internal temperature measurement exceeds a programmed temperature threshold for a programmed delay.
  • Page 52: I 2 C Communications

    C serial communications interface in the BQ769142 device acts as a slave device and supports rates up to 400 kHz with an optional CRC check. If the OTP has not been programmed, the BQ769142 device will initially power up by default in 400 kHz I...
  • Page 53: Spi Communications

    C Read Without Repeated Start 14.3 SPI Communications The SPI interface in the BQ769142 device operates as a slave-only interface with an optional CRC check. If the OTP has not been programmed, the BQ769142 device initially powers up by default in 400 kHz I...
  • Page 54 CRC error was detected. The internal oscillator in the BQ769142 device may not be running when the host initiates a transaction (for example, this can occur if the device is in SLEEP mode). If this occurs, the interface will drive out 0xFFFF on SPI_MISO for the first 16-bits clocked out.
  • Page 55 CRC is enabled (with the exceptions associated with 0xFFFF as noted above). A diagram of three transaction sequences with and without CRC are shown below, assuming CPOL=0. Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback...
  • Page 56 SPI_MISO R/W bit & 7-bit 8-bit write 8-bit CRC address # 1 data # 1 (for previous two bytes) Figure 14-6. SPI Transaction #2 Using CRC Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ769142...
  • Page 57 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 Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ769142...
  • Page 58 # 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 Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ769142...
  • Page 59: Hdq Communications

    BQ769142 device using a single-wire connection to the ALERT pin or the HDQ pin, depending on configuration. Both the master (host device) and slave (BQ769142) drive the HDQ interface using an open-drain driver, with a pullup resistor from the HDQ interface to a supply voltage required on the circuit board. The BQ769142 device...
  • Page 60: Cell Balancing

    BQ769142 Technical Reference Manual. Due to the current that flows into the cell input pins on the BQ769142 device while balancing is active, the measurement of cell voltages and evaluation of cell voltage protections by the device is modified during balancing.
  • Page 61: Application And Implementation

    16.1 Application Information The BQ769142 device can be used with 3-series to 14-series battery packs, supporting a top-of-stack voltage ranging from 5 V up to 80 V. To design and implement a comprehensive set of parameters for a specific battery pack, during development the user can use Battery Management Studio (BQSTUDIO), which is a graphical user- interface tool installed on a PC.
  • Page 62 400 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. Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ769142...
  • Page 63 BQ769142 for a 14- series battery pack. The BQ76952 EVM also provides a good reference design for BQ769142, noting that the VC12 - VC16 connections in the BQ76952 EVM need to be modified as shown in Figure 16-1.
  • Page 64 TP19 0.1uF PGND 5.1k 7.50k TP20 PACK LD 5.1k TP21 TP22 PGND TP23 100V PACK 5.1k 5.1k 5.1k 5.1k Figure 16-3. BQ769142 14-Series Cell Schematic Diagram—Additional Circuitry Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ769142...
  • Page 65 SLUSE91A – SEPTEMBER 2020 – REVISED FEBRUARY 2021 The board layout for a similar design using the BQ76952 for a 16-series battery pack is shown in Section 18.2. 16.2.1 Design Requirements (Example) Table 16-1. BQ769142 Design Requirements DESIGN PARAMETER EXAMPLE VALUE Minimum system operating voltage 35 V Cell minimum operating voltage 2.5 V...
  • Page 66 • Protection FET selection and configuration – The BQ769142 device is designed for use with high-side NFET protection (low-side protection NFETs can be used by leveraging the DCHG / DDSG signals). – The configuration should be selected for series versus parallel FETs, which may lead to different FET selection for charge versus discharge direction.
  • Page 67: Random Cell Connection Support

    PACK pin voltage, LD pin voltage, current measurement, and individual temperature measurements. 16.3 Random Cell Connection Support The BQ769142 device supports a random connection sequence of cells to the device during pack manufacturing. For example, cell-10 in a 14-cell stack might be first connected at the input terminals leading to pins VC10 and VC9, then cell-4 may next be connected at the input terminals leading to pins VC4 and VC3, and so on.
  • Page 68: Startup Timing

    16.4 Startup Timing At initial power up of the BQ769142 device from a SHUTDOWN state, the device progresses through a sequence of events before entering NORMAL mode operation. These are described below for an example configuration, with approximate timing shown for the cases when [FASTADC] = 0 and [FASTADC] = 1.
  • Page 69: 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. Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links:...
  • Page 70 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. Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ769142...
  • Page 71: 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. Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links:...
  • Page 72: Power Supply Requirements

    17 Power Supply Requirements The BQ769142 device draws its supply current from the BAT pin, which is typically connected to the top of stack point through a series diode, to protect against any fault within the device resulting in unintended charging of the pack.
  • Page 73: Layout Example

    • The BQ769142 device internal REG18 LDO requires an external decoupling capacitor, which should be placed as close to the REG18 pin as possible, with minimized trace inductance, and connected to a ground plane electrically connected to VSS.
  • Page 74 BQ769142 www.ti.com SLUSE91A – SEPTEMBER 2020 – REVISED FEBRUARY 2021 Figure 18-1. BQ76952 Two-Layer Board Layout–Top Layer Submit Document Feedback Copyright © 2021 Texas Instruments Incorporated Product Folder Links: BQ769142...
  • Page 75 BQ769142 www.ti.com SLUSE91A – SEPTEMBER 2020 – REVISED FEBRUARY 2021 Figure 18-2. BQ76952 Two-Layer Board Layout–Bottom Layer Copyright © 2021 Texas Instruments Incorporated Submit Document Feedback Product Folder Links: BQ769142...
  • Page 76: Device And Documentation

    All trademarks are the property of their respective owners. 19.5 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 77 RoHS & Green NIPDAU Level-2-260C-1 YEAR -40 to 85 BQ769142 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.
  • Page 78 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 80 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...

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