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

15 Setting Up the Power Stage Board Hardware

The power-stage board can be set up in the following steps:

  • Each DC/DC converter stage can be tested independently. If both stages are being used, each stage switches 180° out-of-phase to lower the input capacitor current ripple.
  • J1 is the input connector to the first power stage buck converter. Apply a voltage to J1 that is higher than the battery voltage to charge including 15% overhead for the duty cycle limitation of the converter.
  • The 20-kHz PWM inputs from the MSP430F5510 microprocessor board feed into I_PWM1 and V_PWM1. Analog voltages could also be fed onto these pins to control the output voltage and current of the DC/DC controller.
  • A protection diode is used on the output of each power stage to protect the converter and prevent discharge of the battery. For output currents less than 5 A, the surface mount output diode can be used. For current levels from 5 to 10 A, heatsinking is required to remove heat from the TO-220 diode.
  • To test the reverse polarity and overvoltage protection, apply the input voltage to J9. The voltage on J8 feeding VIN and VIN_2 is limited by the breakdown voltage of zener diode D4. In an overvoltage condition, both DC/DC converters are shut off by signals SD1 and SD2 but continue to power the microprocessor though the Vbias voltage created by Q6 discrete linear regulator.