I have a circuit using AD620 and AD820 opamps, and am trying to figure out the simplest way to integrate a high pass AND a lowpass filter.
The context of each component within the circuit currently matches these examples...
I've found examples and explanations online and in the data sheets explaining how to create low pass filters, but cannot find anything about high pass filters.
To create a high pass filter, would it be as simple as flipping the resistors and capacitors? Does anyone know of documentation describing how to integrate high pass filters around these components?
The following paper creates a high pass filter by putting a capacitor and resistor in the place of the gain resistor on a AD620. EMG signals contain large offsets that must be filtered by a high pass filter. I found no mention of using this technique in the AD620 data sheet and wonder if there isn't some ill effects with the idea (i.e. dielectric absorption, leakage or temp effects). Perhaps Analog devices could give some more information on the idea. I have simulated it LTspice with a AD623 and it works well as a high pass filter.
Design of a High–Resolution Surface Electromyogram (EMG) Conditioning Circuit