Pulse based signal processing: VLSI implementation of a Palmo filter

A new VLSI signal processing implementation technique is presented that uses a Pulse Width Modulation (PWM) signal representation combined with simple analogue processing to produce an electronically-programmable, process-tolerant filter building block. The principle benefits of this technique include full programmability, reconfigurability and testability which makes the technique an attractive proposition for VLSI. A 4th order Palmo filter is simulated and compared with the ideal response to demonstrate the validity of this novel approach. Preliminary results from a working chip demonstrate the operation of an analogue to PWM signal converter and the Palmo integrator.