Charge domain recursive filters
Abstract
A new architecture is presented that permits the implementation of both poles and zeros in the transfer function of analogsampled data filters without requiring any active gain elements. It is shown that useful filters can be implemented by splitting and summing minority carrier charge packets that represent the input signal in order to form new charge packets that represent the output. Since the feedback and feedforward coefficients in this architecture are all less than unity, absolute stability is guaranteed regardless of the 'Q' of the poles. In contrast to the splitelectrode architecture, where the capacitancevoltage characteristic influences the linearity of summation, this operation is strictly linear in charge domain filters. Accurate and highly linear multiplication can be achieved in the charge domain by splitting packets into portions that contain charge in direct proportion to their respective areas.
 Publication:

IEEE Journal of SolidState Circuits
 Pub Date:
 June 1982
 DOI:
 10.1109/JSSC.1982.1051783
 Bibcode:
 1982IJSSC..17..597T
 Keywords:

 Analog Data;
 Data Sampling;
 Digital Filters;
 Network Synthesis;
 Signal Processing;
 Transfer Functions;
 Architecture;
 Capacitance;
 Charge Transfer Devices;
 Minority Carriers;
 Recursive Functions;
 VoltAmpere Characteristics;
 Electronics and Electrical Engineering