ExG Notch Flex Module

Our 3dB needs moved from 1KHz down to 200Hz according to Plessey. This should minimize the amount of wasted energy in amplification/ADC and reduce overall noise.

We will be upgrading the op amps on these boards to a much more precise design ST recommends. It should improve performance and not significantly increase cost.

This design heavily utilizes a single op amp to do multiple things. It is two complex filters and a summation amplifier all in one. We may need an additional amplification of the output, if so we will create a new Flex Module that is 2 channels.

We are calling this module ExG, though it will mostly be used for ECG sensing. The design allows for a variety of biosensing.