Piecewise linear operations on sigma-delta modulated signals

Piecewise linear (PWL) circuits operating on sigma-delta (/spl Sigma//spl Delta/) modulated signals are proposed. The proposed circuit library includes an absolute circuit, a min/max selector and a negative resistance. As an application of the PWL circuits, a median filter is presented. It is structured with 23% of logic gates consumed by an equivalent filter with 8-bit parallel signal form. It is expected that application of /spl Sigma//spl Delta/ domain signal processing including proposed PWL operations to other modern information processing and communication systems such as neural networks and chaotic communication systems will reduce their hardware cost.