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Good differential OpAmp with low offset

Hi,

for an application using the AD9650-25, I require a differential OpAmp as ADC driver with an input voltage offset lower than 10µV. Does Analog Devices offer such an amplifier? I could not find anything so far.

Regards,

Lizzy

Thread Notes

Lizzy,

  I don't know of any manufacturer that makes an op amp with gbw of 250 MHz (Need to be at least 10x your signal freq) and a max Vos of 10 uV.  The zero drift/autozero/chopper parts are usually 5kHz-2.5MHz.

For signal chains with high speed ADCs, we usually see a zero and full scale calibration done in software.

If the offset is less than 1 mV and the gain in the signal chain is low so you don't overload a node,

this works fine.

The data sheet shows an ADA4938-2 (figure 79), so this should work for you.

Harry

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