Other Parts Discussed in Thread: BQ25750, BQSTUDIO, EV2400,
Tool/software:
I am working with the BQ25750 Evaluation Module and having difficulty achieving some of its basic functionality. I have spent a lot of time reviewing documentation and attempting to debug my setup, but continue to observe odd behavior. I am hoping that someone might be able to point out what I am missing.
Here are the details of what I am encountering while using the BQ25750 EVM:
Test Setup:
Default configuration of the EVM (jumpers as listed defaults), using the EVM2400 for interfacing I2C back to bqStudio using the Charger_2_00-bq25750.bqz profile, power supply input on J1, nothing connected on J3 (battery) or on J2 (system).
Observed Behavior:
Regardless of the power supply settings (tested from 10V to 40V, 8A), power is not passed through to the system output (J2) and the PG pin is high and PG register is 0 / "Not Power Good". The chip is responsive over I2C, and probing TP32 (3V3 PULLUP) reads 3.3V as expected. The chip will not perform any ADC conversions and reverts the ADC_EN to 0 immediately (with watchdog disabled, in both continuous sampling and one-shot).
The same behavior is observed with a Li-ion battery (10.95V 3 cell pack, JP1 removed, JP2 set to 34.6 kOhm) attached to J3, system load (~11V @ 3A) to J2, and with or without power supplied to J1. Power does not flow for charging or system operation. If only a battery is connected to J3 (remove J1 power supply), the chip itself does not communicate over I2C.
Primary Question:
Provided I am not missing something obvious in my testing approach, is there a recommended set of diagnostic steps to determine if there is a problem with the BQ25750 chip itself?
The evaluation board is brand new, so I hesitate in thinking there is a problem with it. Any guidance that can be provided is greatly appreciated. The register values observed with a power supply connected to J1 set to 20V, 8A are attached.
Thanks,
Zack
* Created: Mon Jul 15 15:42:57 CDT 2024 * * Format: Register Name tab Character,\t Register Address tab Character,\t Hexadecimal register value. * Device: BQ25750 * BQZ Container: Charger_2_00-bq25750.bqz * Charge Voltage Limit 0010 Charge Current Limit 0640 Input Current DPM Limit 0640 Input Voltage DPM Limit 0348 Reverse Mode Input Current Limit 0640 Reverse Mode System Voltage Limit 03E8 Precharge Current Limit 0140 Termination Current Limit 00A0 Precharge and Termination Control 08 Timer Control 05 Charger Control 09 Pin Control C0 Power Path and Reverse Mode Control 20 MPPT Control 20 TS Charging Threshold Control 96 TS Charging Region Behavior Control 56 TS Reverse Mode Threshold Control 40 Reverse Undervoltage Control 00 VAC Max Power Point Detected 0000 Charger Status 1 00 Charger Status 2 00 Charger Status 3 00 Fault Status 00 Charger Flag 1 00 Charger Flag 2 00 Fault Flag 00 Charger Mask 1 00 Charger Mask 2 00 Fault Mask 00 ADC Control 20 ADC Channel Control 02 IAC ADC - Use Field View 0000 IBAT ADC - Use Field View 0000 VAC ADC 0000 VBAT ADC 0000 VSYS ADC 0000 TS ADC 0000 VFB ADC 0000 Gate Driver Strength Control 00 Gate Driver Dead Time Control 00 Part Information 02 GM Adjust 00 Reverse Mode Battery Discharge Current 02
