high side current sense problem

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jayzac

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Below attached my design for high side current sense with gain of 33. When i vary my current from 80mA to 250mA. The output of the current sense still remain 1.55V. Why there is no changes for the output of current sense?
 

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Do you have your +Vin, -Vin the wrong way around?
 

I connect based on the data sheet



Is there anything wrong ?
 

No, you are correct. It is driving pnp transistor.
 

If the connection is correct, theoretically with vary current the current sense output will be vary too. For my case the current sense output doesn't change at all. At first i thought my IC burned,so i replaced with new one , sadly result is still the same
 

I can see no errors with your circuit.
Are you driving a load from Vout?
If, so, try it unloaded.
 

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