Part Number: BQ27GDK000EVM
I had trouble completing a learning cycle using a the custom designed board with the BQ27530 fuel gauge and BQ24161 so I purchased the BQ27GDK000EVM. I connected a BQ27530EVM, not the custom board, and attached the battery pack that will be used for the design to the BQ27530EVM. I connected the SYS to EXT Load+ J4 and GND to EXT Load- J8 on the GDK board. I ran a charge discharge cycle and everything seemed to work fine with a charge current of 1000mA and a discharge current of 480mA. I submitted the zip file to the GPC calculator and selected the suggested chemistry ID in bqStudio and .
Next I began the learning cycle using the script for GDK in bqStudio. The first attempt stopped at the charging stage since the design capacity is 4800mAh and the DCby2 was 2400mA but the maximum is 2000mA so the script stopped. I modified the script so the maximum charge rate to 2000mA and started the process again.
The script issued the command to start the discharge cycle and it began to discharge at the DCby5 rate 960mA. At some point the discharge current reduced to 12mA. Now even using the manual Discharge Control for GDK, no matter what I set the discharge current to it never discharges any higher than 12mA. I have power cycled the GDK and even completely disconnected all the EVM boards and connected them back. I reset the BQ27530-G1 data memory back to the default thinking something during the learning cycle caused the discharge current to be limited.
I am attaching the log file that was being captured during the learning cycle that shows around line 4540 the current went from -948 to -12. I don’t see any changes in measurements or the register values.
Is there any suggestion on what I should look for that would be causing the GDK to only discharge at 12mA?
I checked the fuses F1 and F3 which are in the area of the GDK load and both were good. I tried to look at the schematic for the GDK to probe some test points but the quality of the schematic images in the manual are so poor I can not read the reference designators.
