The tau-cell: a new method for the implementation of arbitrary differential equations

In this paper we present the tau-cell, a building block based on a log-domain low-pass filter, which allows the creation of arbitrary differential equations using a cascade of these cells in a manner similar to the state variable methods of filter realization. In the tau-cell implementation, however, all feedback is local, i.e., each first-order section only feeds back to the previous first-order section in the cascade.