SLUUBW5A July   2018  – September 2021 BQ34Z100-G1

 

  1. 1 Read This First
    1. 1.1 About This Manual
    2. 1.1 Notational Conventions
    3. 1.1 Glossary
    4. 1.1 Trademarks
  2. 1 Introduction
  3. 2 Data Commands
    1. 2.1 Standard Data Commands
      1. 2.1.1  Control(): 0x00/0x01
        1. 2.1.1.1  CONTROL_STATUS: 0x0000
        2. 2.1.1.2  DEVICE TYPE: 0x0001
        3. 2.1.1.3  FW_VERSION: 0x0002
        4. 2.1.1.4  HW_VERSION: 0x0003
        5. 2.1.1.5  RESET_DATA: 0x0005
        6. 2.1.1.6  PREV_MACWRITE: 0x0007
        7. 2.1.1.7  CHEM ID: 0x0008
        8. 2.1.1.8  BOARD_OFFSET: 0x0009
        9. 2.1.1.9  CC_OFFSET: 0x000A
        10. 2.1.1.10 CC_OFFSET_SAVE: 0x000B
        11. 2.1.1.11 DF_VERSION: 0x000C
        12. 2.1.1.12 SET_FULLSLEEP: 0x0010
        13. 2.1.1.13 STATIC_CHEM_DF_CHKSUM: 0x0017
        14. 2.1.1.14 SEALED: 0x0020
        15. 2.1.1.15 IT ENABLE: 0x0021
        16. 2.1.1.16 CAL_ENABLE: 0x002D
        17. 2.1.1.17 RESET: 0x0041
        18. 2.1.1.18 EXIT_CAL: 0x0080
        19. 2.1.1.19 ENTER_CAL: 0x0081
        20. 2.1.1.20 OFFSET_CAL: 0x0082
      2. 2.1.2  StateOfCharge(): 0x02
      3. 2.1.3  MaxError(): 0x03
      4. 2.1.4  RemainingCapacity(): 0x04/0x05
      5. 2.1.5  FullChargeCapacity(): 0x06/07
      6. 2.1.6  Voltage(): 0x08/0x09
      7. 2.1.7  AverageCurrent(): 0x0A/0x0B
      8. 2.1.8  Temperature(): 0x0C/0x0D
      9. 2.1.9  Flags(): 0x0E/0x0F
      10. 2.1.10 FlagsB(): 0x12/0x13
      11. 2.1.11 Current(): 0x10/0x11
    2. 2.2 Extended Data Commands
      1. 2.2.1  AverageTimeToEmpty(): 0x18/0x19
      2. 2.2.2  AverageTimeToFull(): 0x1A/0x1B
      3. 2.2.3  PassedCharge(): 0x1C/0x1D
      4. 2.2.4  DOD0Time(): 0x1E/0x1F
      5. 2.2.5  AvailableEnergy(): 0x24/0x25
      6. 2.2.6  AveragePower(): 0x26/0x27
      7. 2.2.7  SerialNumber(): 0x28/0x29
      8. 2.2.8  InternalTemperature(): 0x2A/0x2B
      9. 2.2.9  CycleCount(): 0x2C/0x2D
      10. 2.2.10 StateOfHealth(): 0x2E/0x2F
      11. 2.2.11 ChargeVoltage(): 0x30/0x31
      12. 2.2.12 ChargeCurrent(): 0x32/0x33
      13. 2.2.13 PackConfiguration(): 0x3A/0x3B
      14. 2.2.14 DesignCapacity(): 0x3C/0x3D
      15. 2.2.15 DataFlashClass(): 0x3E
      16. 2.2.16 DataFlashBlock(): 0x3F
      17. 2.2.17 AuthenticateData/BlockData(): 0x40…0x53
      18. 2.2.18 AuthenticateChecksum/BlockData(): 0x54
      19. 2.2.19 BlockData(): 0x55…0x5F
      20. 2.2.20 BlockDataChecksum(): 0x60
      21. 2.2.21 BlockDataControl(): 0x61
      22. 2.2.22 GridNumber(): 0x62
      23. 2.2.23 LearnedStatus(): 0x63
      24. 2.2.24 Dod@Eoc(): 0x64/0x65
      25. 2.2.25 QStart(): 0x66/0x67
      26. 2.2.26 TrueRC(): 0x68/0x69
      27. 2.2.27 TrueFCC(): 0x6A/0x6B
      28. 2.2.28 StateTime(): 0x6C/0x6D
      29. 2.2.29 QmaxPassedQ(): 0x6E/0x6F
      30. 2.2.30 DOD0(): 0x70/0x71
      31. 2.2.31 QmaxDod0(): 0x72/0x73
      32. 2.2.32 QmaxTime(): 0x74/0x75
      33. 2.2.33 Data Flash Interface
        1. 2.2.33.1 Accessing Data Flash
        2. 2.2.33.2 Manufacturer Information Block
        3. 2.2.33.3 Access Modes
        4. 2.2.33.4 Sealing/Unsealing Data Flash Access
  4. 3 Fuel Gauging
    1. 3.1  Overview
    2. 3.2  Impedance Track Variables
      1. 3.2.1  Load Mode
      2. 3.2.2  Load Select
      3. 3.2.3  Reserve Cap-mAh
      4. 3.2.4  Reserve Cap-mWh/cWh
      5. 3.2.5  Design Energy Scale
      6. 3.2.6  Dsg Current Threshold
      7. 3.2.7  Chg Current Threshold
      8. 3.2.8  Quit Current, Dsg Relax Time, Chg Relax Time, and Quit Relax Time
      9. 3.2.9  Qmax
      10. 3.2.10 Update Status
      11. 3.2.11 Avg I Last Run
      12. 3.2.12 Avg P Last Run
      13. 3.2.13 Cell Delta Voltage
      14. 3.2.14 Ra Tables
      15. 3.2.15 StateOfCharge() Smoothing
      16. 3.2.16 Charge Efficiency
      17. 3.2.17 Lifetime Data Logging
    3. 3.3  Device Configuration
      1. 3.3.1 Pack Configuration Register
      2. 3.3.2 Pack Configuration B Register
      3. 3.3.3 Pack Configuration C Register
    4. 3.4  Voltage Measurement and Calibration
      1. 3.4.1 1S Example
      2. 3.4.2 7S Example
      3. 3.4.3 Autocalibration
    5. 3.5  Temperature Measurement
    6. 3.6  Overtemperature Indication
      1. 3.6.1 Overtemperature: Charge
      2. 3.6.2 Overtemperature: Discharge
    7. 3.7  Charging and Charge Termination Indication
    8. 3.8  SCALED Mode
    9. 3.9  LED Display
    10. 3.10 Alert Signal
  5. 4 Communications
    1. 4.1 Authentication
    2. 4.2 Key Programming
    3. 4.3 Executing an Authentication Query
    4. 4.4 HDQ Single-Pin Serial Interface
    5. 4.5 I2C Interface
    6. 4.6 Switching Between I2C and HDQ Modes
      1. 4.6.1 Converting to HDQ Mode
      2. 4.6.2 Converting to I2C Mode
  6. 5 Device Functional Modes
    1. 5.1 NORMAL Mode
    2. 5.2 SLEEP Mode
    3. 5.3 FULL SLEEP Mode
  7. 6 Power Control
    1. 6.1 Reset Functions
    2. 6.2 Wake-Up Comparator
    3. 6.3 Flash Updates
  8. 7 Data Flash Summary
  9. 8 Gas Gauge Timing Considerations
    1. 8.1 Gauging Effects on I2C Transactions
    2. 8.2 HDQ Bus Effects on Gauging
    3. 8.3 Gauging Effects on HDQ Transactions
    4. 8.4 Manufacturer Timing Notes
  10. 9 HDQ Communication Basics
    1. 9.1 Basic HDQ Protocol
    2. 9.2 Break
    3. 9.3 Basic Timing
    4. 9.4 Reading 16-Bit Words
    5. 9.5 Host Processor Interrupts Using Discrete I/O Port for HDQ
    6. 9.6 Using UART Interface to HDQ
  11. 10Procedures to Seal and Unseal the Gauge
    1. 10.1 Unseal the Gauge to UNSEALED Mode
    2. 10.2 Unseal the Gauge to FULL ACCESS Mode
    3. 10.3 Seal the Gauge
  12. 11Impedance Track Gauge Configuration
    1. 11.1 Introduction
    2. 11.2 Determining ChemID
    3. 11.3 Learning Cycle
    4. 11.4 Common Problems Seen During the Learning Cycle
    5. 11.5 Test Gauge and Optimize
    6. 11.6 Finalize Golden File
    7. 11.7 Program and Test the PCB
  13. 12Revision History

1 Introduction

The BQ34Z100-G1 device is an Impedance Track™ fuel gauge for Li-Ion, PbA, NiMH, and NiCd batteries, and works independently of battery series-cell configurations. Batteries from 3 V to 65 V can be easily supported through an external voltage translation circuit that is controlled automatically to reduce system power consumption.

  • Supports Li-Ion, LiFePO4, PbA, NiMH, and NiCd Chemistries
  • Capacity Estimation Using Patented Impedance Track™ Technology for Batteries from 3 V to 65 V
    • Aging Compensation
    • Self-Discharge Compensation
  • Supports Battery Capacities up to 29 Ah with Standard Configuration Options
  • Supports Charge and Discharge Currents up to 32 A with Standard Configuration Options
  • External NTC Thermistor Support
  • Supports Two-Wire I2C and HDQ Single-Wire Communication Interfaces with Host System
  • SHA-1/HMAC Authentication
  • One- or Four-LED Direct Display Control
  • Five-LED and Higher Display Through Port Expander
  • Reduced Power Modes (Typical Battery Pack Operating Range Conditions)
    • Normal Operation: < 145-μA Average
    • Sleep: < 84-μA Average
    • Full Sleep: < 30-μA Average
  • Package: 14-Pin TSSOP

The BQ34Z100-G1 device accurately predicts the battery capacity and other operational characteristics of a single cell or multiple rechargeable cell blocks, which are voltage balanced when resting. The device supports various Li-Ion, Lead Acid (PbA), Nickel Metal Hydride (NiMH), and Nickel Cadmium (NiCd) chemistries, and can be interrogated by a host processor to provide cell information, such as remaining capacity, full charge capacity, and average current.

Information is accessed through a series of commands called Standard Commands (see Section 3.1). Further capabilities are provided by the additional Extended Commands set (see Section 3.2). Both sets of commands, indicated by the general format Command(), are used to read and write information contained within the BQ34Z100-G1 device’s control and status registers, as well as its data flash locations. Commands are sent from host to gauge using the BQ34Z100-G1 serial communications engines, HDQ and I2C, and can be executed during application development, pack manufacture, or end-equipment operation.

Cell information is stored in the BQ34Z100-G1 in non-volatile flash memory. Many of these data flash locations are accessible during application development and pack manufacture. They cannot, generally, be accessed directly during end-equipment operation. Access to these locations is achieved by using the BQ34Z100-G1 device’s companion evaluation software, through individual commands, or through a sequence of data-flash-access commands. To access a desired data flash location, the correct data flash subclass and offset must be known.

The BQ34Z100-G1 provides 32 bytes of user-programmable data flash memory. This data space is accessed through a data flash interface. For specifics on accessing the data flash, refer to Section 3.2.33.

The key to the BQ34Z100-G1 device’s high-accuracy gas gauging prediction is Texas Instrument’s proprietary Impedance Track algorithm. This algorithm uses voltage measurements, characteristics, and properties to create state-of-charge predictions that can achieve accuracy with as little as 1% error across a wide variety of operating conditions.

The BQ34Z100-G1 measures charge/discharge activity by monitoring the voltage across a small-value series sense resistor connected in the low side of the battery circuit. When an application’s load is applied, cell impedance is measured by comparing its Open Circuit Voltage (OCV) with its measured voltage under loading conditions.

The BQ34Z100-G1 can use an NTC thermistor (default is Semitec 103AT or Mitsubishi BN35-3H103FB-50) for temperature measurement, or can also be configured to use its internal temperature sensor. The BQ34Z100-G1 uses temperature to monitor the battery-pack environment, which is used for fuel gauging and cell protection functionality.

To minimize power consumption, the BQ34Z100-G1 has three power modes: NORMAL, SLEEP, and FULL SLEEP. The BQ34Z100-G1 passes automatically between these modes, depending upon the occurrence of specific events.

Multiple modes are available for configuring from one to 16 LEDs as an indicator of remaining state of charge. More than four LEDs require the use of one or two inexpensive SN74HC164 shift register expanders.

A SHA-1/HMAC-based battery pack authentication feature is also implemented on the BQ34Z100-G1. When the IC is in UNSEALED mode, authentication keys can be (re)assigned. A scratch pad area is used to receive challenge information from a host and to export SHA-1/HMAC encrypted responses. See the Section 5.1 section for further details.