BQ24105: Accuracy of TS pin setting

Ben Kuo

Part Number: BQ24105

Dear team,

Customer faced to OTP issue on their board.

They set-up battery operating temperature from 0 to 45 degree. (NTC spec in attachment)

But charging status stop in 50 degree instead of 45 degree they expect.

Could you help to check if this issue is tolerance issue or system design issue?

please contact with me offline and I can share schematic with you to double confirm this.

Regards,

Ben

benkuo@ti.com

0 Ricardo over 5 years ago

Ben,

Could you please provide the customer's values for RT2 and RT1?

Thanks,

Ricardo

0 Ben Kuo over 5 years ago in reply to Ricardo

Hi Ricardo,

Currently, they use RT1=82K and RT2=681K-ohm

Note: RT1 should be 78.7K-ohm, but customer don't 78.7K-ohm resistor on hand.

Ben

0 Ricardo over 5 years ago in reply to Ben Kuo

Ben,

By my calculations, with RT1=82k and RT2=681k, the customer should start charging at -0.29C and stop charging at 43.62C.

This is roughly what the customer wants. Could you have the customer measure the thermistor (disconnected) at these temperatures?

Also is there anything else connected to the thermistor network?

Thanks,

Ricardo

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