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BQ2970: Using precision resistor in series with FETs to set max charge/discharge current

Part Number: BQ2970
Other Parts Discussed in Thread: BQ2980

Hello,

Referring to this old post: https://e2e.ti.com/support/power-management/f/power-management-forum/426410/bq29700-for-50mahr-battery, where a precision resistor is proposed to be used in series with the CHG and DSG FETs, to set the max discharge and charge current, I want to verify: Has anyone attempted this? Does it work?

I have found it particularly hard to find FETs with a good Rdson value to fit my needs (I need max 0.5 A charge/discharge). Using a series resistor would make this so much simpler. Of course I would still use the CHG and DSG FETs, but with a negligible Rdson when compared to the resistor.

So, in summary:

1. Can you use a precision resistor in series with the FETs in the BQ2970, to set the max charge/discharge current?

2. If so, how would I calculate the max power dissipated through the resistor? I'd be using a single cell, 3V7 li-ion battery.

If anyone can help, I'd appreciate it!

Best,

Dan