Charge domain recursive filters

A new charge-transfer device architecture has been developed for implementing recursive filters in the minority charge domain. A three pole filter using this architecture has been designed and fabricated. The measured filter characteristics are in close agreement with theoretical predictions to approximately 0.2 percent. The charge domain filter appears to retain the intrinsic CCD shift register advantages (e.g. high-speed, small output capacitance, wide linear dynamic range), while overcoming many of the disadvantages of the present CCD transversal filter architecture.