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This signal acquisition circuit board was designed for a manufacturer of FTIR spectrometers. The circuit board provided various functions including A/D conversion, mirror motion detection via laser quadrature signals, and a host of signal processing applications using a digital signal processor. The design was carried out from concept to finished circuit board, including all onboard programming.

The A/D converter was a custom design that produced 16-bit resolution at a 1 MHz sample rate. Cost was an issue in this design so a method was developed that was tailored to this application.

Signal processing included FIR filtering, application of a polynomial to linearize the A/D converter signal, multiple scan accumulation, FFTs, anomaly detection, etc.