LM61460: shunt resistor used for power supply

liping pan

Part Number: LM61460

To measure current during sleep, I would like to add 100mohm shunt resistor in below position (marked with red), and the measured by amplifier+ADC circuit.

Let me know if there is any risk for power supply control loop.

9 months ago

0 Jimmy Hua 9 months ago

TI__Guru 50120 points

Hi,

I think it would be better to place the 100mOhm resistor after the feedback divider and feedforward circuit.

So place the resistor after Rff/Cff and it should not be part of the internally control loop but will allow you to measure the output current.

Regards.

Jimmy

0 liping pan 9 months ago in reply to Jimmy Hua

Intellectual 460 points

But it will cause additional voltage drop on 100mohm resistor which can not be compensated.

+1 Jimmy Hua 9 months ago in reply to liping pan

TI__Guru 50120 points

Hi,

Thanks for clarifying.

In that case, you can place it inside the loop.

Generally I would not put it inside the loop but I don't think the 100mOhm would impact it too much.

Regards,

Jimmy

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LM61460: shunt resistor used for power supply