BQ25713: RSNS_RSR setting 20 mΩ shunt

THOMAS WALTER

Prodigy 130 points

Part Number: BQ25713

Hi,

I am using the BQ25713 with a 20 mΩ charge shunt.
I set the bit 2 (RSNS_RSR ) of register 31h to 1, .

The charge current I set is divided by 2 (asking 1024mA and reading 500mA with current clamp).

Is it a normal behavior ? I thought that setting RSNS_RSR would fix this.

Thanks.

over 1 year ago

+1 Tiger Zhou over 1 year ago

TI__Mastermind 32745 points

Hi, Thomas,

This is normal. The charger does not know the current sense value. It detects the voltage drop across the current sense and regulate with the ICHG setting value.

We need to scale up or down depending on the current sense value.

For example,

1A *10mohm = 0.5A *20mohm =2A *5mohm.

The RSNS_RSR is mainly for PSYS function.

Regards,

Tiger

0 THOMAS WALTER over 1 year ago in reply to Tiger Zhou

Prodigy 130 points

Pefect, thanks for your answer.

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BQ25713: RSNS_RSR setting 20 mΩ shunt