Electronic – Very low frequency instrumentation amplifier


I'm trying to choose an instrumentation amplifier for very low frequency signals (seismic monitoring).

The trouble I'm finding is that on many of the data sheets, they only give response curves down to 10Hz or even 100Hz. I need to know the performance at .01Hz or .1Hz.

Could anyone please suggest a suitable component for this task?

Many thanks in advance,

Best Answer

Like The Photon says, they work down to DC, it's just that most customers don't use them for those very low frequencies, so they don't publish data on them.

I checked InAmps at Digikey with low slew rates, they will be better suited for your application. The AD8235, for instance, has a slew rate of 0.011 V\$\mu\$s, and the datasheet show graphs for noise, CMRR, and such down to 0.1 Hz.