SLAA476B February   2011  – July 2019 BQ2040 , BQ2040 , BQ2060A , BQ2060A , BQ2063 , BQ2063 , BQ2083-V1P3 , BQ2083-V1P3 , BQ2084-V143 , BQ2084-V143 , BQ2084-V150 , BQ2084-V150 , BQ2085-V1P3 , BQ2085-V1P3 , BQ20Z40-R1 , BQ20Z40-R1 , BQ20Z70-V160 , BQ20Z70-V160 , BQ20Z80A-V110 , BQ20Z80A-V110 , BQ28400 , BQ28400 , BQ78PL114 , BQ78PL114 , BQ78PL116 , BQ78PL116 , LM5145 , LM5145 , MSP430F5500 , MSP430F5500 , MSP430F5501 , MSP430F5501 , MSP430F5502 , MSP430F5502 , MSP430F5503 , MSP430F5503 , MSP430F5504 , MSP430F5504 , MSP430F5505 , MSP430F5505 , MSP430F5506 , MSP430F5506 , MSP430F5507 , MSP430F5507 , MSP430F5508 , MSP430F5508 , MSP430F5509 , MSP430F5509 , MSP430F5510 , MSP430F5510 , TPS40057 , TPS40057 , TPS40170 , TPS40170

 

  1.   Wide-Vin Battery Charger Using SMBus Communication Interface Between MSP430™ MCUs and bq Fuel Gauges
    1.     Trademarks
    2. 1  Introduction
    3. 2  Hardware
      1. 2.1 Overall System Description
      2. 2.2 MSP430F5510 Daughterboard Subsystem
        1. 2.2.1 Subsystem Description
        2. 2.2.2 MSP430F5510 Port Pins Functionality Description
      3. 2.3 Power Stage Board Subsystem
        1. 2.3.1 Subsystem Description
        2. 2.3.2 Input Protection Features
        3. 2.3.3 Constant-Voltage and Constant-Current Feedback
    4. 3  Software
      1. 3.1 SMBus Protocol Description
      2. 3.2 Software File Structure
      3. 3.3 API Calls Description
        1. 3.3.1  UCS_Init ( )
        2. 3.3.2  Timer_Init ( )
        3. 3.3.3  PWM_Init ( )
        4. 3.3.4  ADC_Init ( )
        5. 3.3.5  Fan_Init ( )
        6. 3.3.6  LED_Init ( )
        7. 3.3.7  SMBus_Initialize ( )
        8. 3.3.8  LED_Control ( )
        9. 3.3.9  Fan_Control ( )
        10. 3.3.10 VI_ADC_Read ( )
        11. 3.3.11 SMBus_Select ( )
        12. 3.3.12 Calibrate_Battery ( )
        13. 3.3.13 Delay_Timer ( )
        14. 3.3.14 PWM_Control ( )
        15. 3.3.15 Smbus_Access ( )
        16. 3.3.16 Smbus_Access_PEC ( )
        17. 3.3.17 crc8MakeBitwise ( )
      4. 3.4 Sample Application Description
    5. 4  SBS Supported Commands Using SMBus Protocol
    6. 5  Detailed Sample Application Flow Chart
    7. 6  Battery Status Register Description
      1. 6.1 BatteryStatus (0x16)
    8. 7  MSP430F5510 Daughterboard Schematics
    9. 8  Setting Up the MSP430F5510 Daughterboard Hardware
      1. 8.1 JTAG FET Debugger Interface (Power Up, Program and Debug Options)
      2. 8.2 eZ430 Emulator Interface (Power Up, Program and Debug Options)
      3. 8.3 Power Stage Board (Power Up Option Only)
    10. 9  Battery Calibration Circuit Setup
    11. 10 Battery Voltage and PWM Conversions
    12. 11 Battery Current and PWM Conversions
    13. 12 Power Stage Board Schematics (Generation 1: 40-V Input)
    14. 13 Bode Plot Measurement for Feedback Loop Stability Analysis
    15. 14 Power Stage Board Schematics (Generation 2: 60-V Input)
    16. 15 Setting Up the Power Stage Board Hardware
    17. 16 References
  2.   Revision History

9 Battery Calibration Circuit Setup

The MSP430F5510 daughterboard hardware has power resistors that can be connected to battery terminals for discharging. The discharge circuitry can be turned on or off by the microcontroller to calibrate battery pack voltages. There are two independent circuits for calibrating two batteries simultaneously.

  • To enable the calibration circuit for Battery 1, populate J5, pins 1 and 2.
  • To enable the calibration circuit for Battery 2, populate J8, pins 1 and 2.
battery_calibration_circuit_setup_laa476.gifFigure 13. Battery Calibration Circuit Setup

To enable the power FETs, the respective calibration signal from the microcontroller must be set to a logic high (CAL-CH1 or CAL-CH2). This task can be easily accomplished by calling the Calibrate_Battery() function.