SLUUCB5E June   2020  – July 2022 BQ25792 , BQ25798

 

  1.   BQ25792EVM, BQ25798BKUPEVM and BQ25798EVM (BMS034) Evaluation Module
  2. 1Introduction
    1. 1.1 EVM Features
    2. 1.2 I/O Descriptions
    3. 1.3 Recommended Operating Conditions
  3. 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
  4. 3PCB Layout Guidelines
  5. 4Board Layout, Schematic and Bill of Materials
    1. 4.1 BMS034 Board Layout
    2. 4.2 BQ2579XEVM (BMS034) Schematics
    3. 4.3 Bill of Materials
  6. 5Revision History

2.4.4 OTG Mode Verification

Use the following steps for OTG mode verification for boost operation:

  1. Power up then turn off Load#2 output. Set to CR = 12 V/0.5 A = 24 Ω. Disconnect PS1 from J1 and attach Load#2 to J1 (VIN1 and GND).
  2. Increase Load #1 regulation voltage to 8.0 V and take measurements as follows:
    • Measure ➡ VBAT-PGND (TP27 and TP46) = 8.0 V ±0.1 V
  3. For BQStudio, prepare the OTG mode charger register settings in the following way:
    • On the 8-bit Registers tab in the Chip Config Single-bit Registers section:
      • Check the EN OTG Mode box
      • Check the EN ACDRV1 box
    • On the 8-bit Registers tab in the OTG Multi-bit Registers section:
      • Set IOTG 1000 mA to change the OTG current limit.
        GUID-E3498C29-2537-4283-9698-C8C806EC577D-low.png Figure 2-8 Single-Bit Register Section
    • On the 16-bit Registers tab in the OTG Multi-bit Registers section:
      • Set the OTG mode regulation voltage to 12000 mV
        GUID-D51EC4F8-74FA-48C7-BF70-25A4F0779091-low.png Figure 2-9 Multi-Bit Register Section
    For GUI composer, go to OTG Configuration Section and change the following registers:
    • OTG Reg Voltage to 12 V
    • IOTG Limit to 1 A.
      GUID-44AA95D5-92EC-4A74-AAC7-9A0C3A7DA440-low.png Figure 2-10 OTG Configuration Section
    Next go to the Chip configuration and check the EN OTG Mode box and EN ACDRV1 box.
    GUID-434ABECC-86F7-433F-BC81-3D50FA1B6FC1-low.png Figure 2-11 Chip Configuration
  4. Take measurements as follows:
    • Measure ➡ VVBUS-PGND (TP21 and TP45) = 12.0 V ±0.2 V
    • Measure ➡ VAC1-PGND (TP22 and TP45) = 12.0 V ±0.2 V
    • Click READ ALL REGISTERS
      • Verify ➡ REG1Bb[6] reports VINDPM or OTG
      • Verify ➡ REG1Cb[4:1] reports VBUS Status as Normal OTG
  5. Turn on Load#2 output set to CR of 24 Ω.
  6. Take measurements as follows:
    • Measure ➡ VAC1-PGND (TP22 and TP45) = 12.0 V ±0.2 V
    • Measure ➡ IAC1-SENSE (TP1 and TP2) = 500 mA ±0.10 A
  7. Lower the Load#2 CR to 10 Ω.
  8. Take measurements as follows to confirm OTG current function:
    • Measure ➡ VAC1-PGND (TP22 and TP45) < 12.0 V ±0.2 V
    • Measure ➡ IAC1-SENSE (TP1 and TP2) = 1000 mA ±0.10 A
    • Click READ ALL REGISTERS and Verify ➡ REG1Bb[7] reports IINDPM
  9. Hints for further OTG testing:
    • Enabling OTG mode is a two-step process, first enable OTG and then turn on the appropriate AC drive FETs.