BQ34Z100-G1: Sense resistor: can it be connector to the positive side of a battery?

Aram N

Part Number: BQ34Z100-G1

Hi,

I have a BMS which utilizes a sense resistor on the positive side of the battery (the resistor is connected in series between BAT+ and PACK+). Is it possible to utilize the same resistor, connecting SRP to the PACK+ and SRN to the BAT+ (that way the sense resistor would be still connected to SRP and SRN)?

Thanks.

over 7 years ago

0 Bryan Kahler over 7 years ago

TI__Mastermind 25955 points

Hi Aram,

The bq34z100-G1 only supports a low side current sense resistor.

Sincerely,
Bryan Kahler

0 Aram N over 7 years ago in reply to Bryan Kahler

Prodigy 60 points

Bryan,

Is it possible to use a differential op amp to measure the voltage drop on the high side resistor, connecting the output of the op amp to the SRP, while SRN is connected to PACK- (and BAT- as well, of course)?

Thanks.

0 Bryan Kahler over 7 years ago in reply to Aram N

TI__Mastermind 25955 points

Hi Aram,

No, your bias current will change and linearity may be lost. The device is designed for low side current sensing operation.

Sincerely,
Bryan Kahler

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BQ34Z100-G1: Sense resistor: can it be connector to the positive side of a battery?