Using Digital Potentiometers to Design Low Pass Adjustable
The most common filter found in a data acquisition system signal path is a low pass filter. This type of filter is usually used to reduce A/D converter aliasing errors. If there is more than one signal that is applied to the A/D converter through a multiplexer, each signal source
may have its own set of filter requirements, i.e. settling time, fast transition region, etc. Consequently, a variety of filters may be required in the circuit prior to the multiplexer. Usually these filters are implemented with operational amplifiers, combined with fixed resistors and capacitors.
Digital Potentiometers, Low Pass Adjustable Filters, MCP41XXX, MCP42XXX