SLUUC51D june   2020  – july 2023 BQ25790

 

  1.   1
  2.   BQ25790EVM (BMS027) Evaluation Module User's Guide
  3.   Trademarks
  4.   4
  5. 1Introduction
    1. 1.1 EVM Features
    2. 1.2 I/O Descriptions
    3. 1.3 Recommended Operating Conditions
  6. 2Test Setup and Results
    1. 2.1 Equipment
    2. 2.2 Equipment Setup
    3. 2.3 Software Setup
      1. 2.3.1 BQSTUDIO using EV2400
      2. 2.3.2 TI Charger GUI for USB2ANY
    4. 2.4 Test Procedure
      1. 2.4.1 Initial Settings
      2. 2.4.2 Communication Verification
      3. 2.4.3 Charge Mode Verification
      4. 2.4.4 OTG Mode Verification
  7. 3PCB Layout Guidelines
  8. 4Board Layout, Schematic and Bill of Materials
    1. 4.1 Schematic
    2. 4.2 Board Layout
    3. 4.3 Bill of Materials
  9. 5Revision History

2.4.3 Charge Mode Verification

Use the following steps for charge mode verification, including precharge, CC and CV phases for boost operation:

  1. PS1 and Load #1 should be on from Section 2.4.1. In the EVM GUI, it is generally recommended to read REG22-REG27 (or READ ALL REGISTERS) one time in order to show all of the interrupts (from status changes, automated routine completion, faults) that occurred since the last read. Reading those registers a second clears the interrupts. After reading the registers,
    • Verify ➡ REG1B reports all Normal, meaning no DPM loops active and no WD timer fault (bits 7-4), VAC1 Present (bit2), VBUS Present (bit 0) and Power Good (bit 3)
  2. Reinstall the shunt on jumper J19 to enable charge
    • Verify ➡ STAT LED (D14) is lit
  3. Take measurements as follows:
    • Measure ➡ VVBUS-PGND (TP21 and TP45) = 5.0 V ±0.2 V
    • Measure ➡ VBAT-PGND (TP27 and TP46) = 5.0 V ±0.2 V
    • Measure ➡ IBAT_SENSE (voltage across 0.01-Ω resistor between TP17 and TP18) = 240 mA ±60 mA
    • Click READ ALL REGISTERS and Verify ➡ REG1Cb[7:5] reports precharge
  4. Increase Load #1 regulation voltage to 8.0 V and take measurements as follows:
    • Measure ➡ VVBUS-PGND (TP21 and TP45) = 5.0 V ±0.2 V
    • Measure ➡ VBAT-PGND (TP27 and TP46) = 8.0 V ±0.1 V
    • Measure ➡ IBAT_SENSE (voltage across 0.01-Ω resistor between TP17 and TP18) = 500 mA ±50 mA
    • Measure ➡ IVAC1_SENSE (voltage across 0.01-Ω resistor between TP1 and TP2) = 900 mA ±60 mA
    • Click READ ALL REGISTERS and Verify ➡ REG1Cb[7:5] reports fast charge
  5. Increase Load #1 regulation voltage to 8.4 V and take measurements as follows:
    • Measure ➡ VBAT-PGND (TP27 and TP46) = 8.4 V ±0.04 V
    • Measure ➡ IBAT_SENSE (voltage across 0.01-Ω resistor between TP17 and TP18) = 0 mA ±10 mA
    • Click READ ALL REGISTERS and Verify ➡ REG1Cb[7:5] reports termination
  6. Helpful hints when changing voltages and register settings during charge mode:
    • If increasing charge current or adding a load at the SYS J3 terminal, disabling the EN_ILIM (EN_EXTLIM) bit using 8-bit register tab/Charger Single-bit Registers/REG14b[1] and increasing the IINDPM register setting in 16-bit register tab/Charger Multi-bit Registers/REG06b[8:0] will likely be needed.
    • If increasing the input voltage above 8 V for the charger to enter buck mode, increase the VAC_OVP from 7 V default using 8-bit register tab/Charger Multi-bit Registers/REG10b[5:4].
    • The battery configuration is set at startup using the PROG pin (Jumpers JP24 to JP31). The battery configuration can also be changed using 16-bit register tab/Charger Multi-bit Registers/REG0Ab[7:6]. Note that the SYSMIN and charge current charge with cell configuration.
    • The status, fault and interrupt bits report are helpful debug tools.