SLUAA04A june   2020  – may 2023 BQ25150 , BQ25155 , BQ25618 , BQ25619 , TS5A12301E , TS5A3157 , TS5A3159A , TS5A6542

 

  1.   1
  2.   High-Efficiency Charging for TWS Using a 2-Pin Interface
  3.   Trademarks
  4. 1 Introduction
  5. 2 System Overview
    1. 2.1 Charging Case
      1. 2.1.1 BQ25619
      2. 2.1.2 TLV62568P
      3. 2.1.3 TPS22910A
      4. 2.1.4 TS5A12301E
      5. 2.1.5 MCU
    2. 2.2 Earbuds
      1. 2.2.1 BQ25155
      2. 2.2.2 TPS22910A
      3. 2.2.3 TS5A12301E
      4. 2.2.4 BT/SOC
  6. 3 Charging Case Algorithm Implementation
    1. 3.1 Initialization and Main Code
    2. 3.2 UART Interrupt and Output Voltage Adjustment
  7. 4 Earbud Algorithm Implementation
    1. 4.1 Initialization and Main Code
    2. 4.2 Interrupt and Transmission
  8. 5 Test Procedure
  9. 6 Test Results
    1. 6.1 Dynamic Voltage Adjustment
    2. 6.2 BQ25619 with 4.6-V Output
    3. 6.3 Standard Boost with 5V Output
  10. 7 Summary
  11. 8 Schematics
  12. 9 PCB Layout
  13. 10Software
    1. 10.1 Charging Case main.c
    2. 10.2 Earbuds main.c
  14. 11Revision History

2.1.5 MCU

In the system described in this paper, an MSP430FR5529 MCU is used to control the case processing functions. This application requires the MCU to have one UART channel and one GPIO for the communication scheme. For controlling the BQ25619, an I2C channel is needed, and five GPIO pins can also be connected to the BQ25619 for input and control of the device. To control the TLV62568P, a PWM enabled GPIO pin is needed to dynamically control the output of the device, and one additional GPIO can also be used to read the PMID_GOOD pin of the device.

In Section 10.1 the software for the charging case is shown.