BQ40Z60EVM not charging when set up for 2S2P configuration.

Tony Carter

I have the BQ40Z60EVM and used it to charge a 3S stack after changing Cell chemistry to match the batteries. Then I changed the jumper, DA CC1 and CC0 and connected up a 2S2P stack. I also changed Design and Qmax values to match the batteries. It will not charge, BMS is showing 0% at 6533 mV charge. What am I missing?

Also I tried to include the gg file but it trew ap the giant blue folder graphic with no labels What is this trying to tell me?

over 10 years ago

0 ThomasCosby over 10 years ago

TI__Guru 73830 points

Tony,
Did you change the Minimum Voltage Output and Voltage Resolution parameters? They need to be updated when the number of series cells change. See page 58 of the TRM.

Tom

0 Tony Carter over 10 years ago in reply to ThomasCosby

Intellectual 360 points

Funny I was playing with that when it started charging and you sent the response all at the same time. Is the formula correct? Default configuration for the 3S EVAL is 6294 mV but the running the numbers for the the 3S I get 675. I get 713 for 2S and I assume this is mV . Is this correct it seems way off compared to the Default?

0 ThomasCosby over 10 years ago in reply to Tony Carter

TI__Guru 73830 points

The top resistor (332k) is R2 in this case, so it is in the numerator. For 3S, the Minimum Voltage Output = 6283 and the Voltage Resolution = 25.

0 Tony Carter over 10 years ago in reply to ThomasCosby

Intellectual 360 points

Thanks.
So figure 4-1 in the TRM has R1 and R2 reversed. That was fun. Seems to be charging away.

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BQ40Z60EVM not charging when set up for 2S2P configuration.