Accurate and simple CMOS ´one-over´ circuit

Experimental results and analysis of a simple, highly linear CMOS circuit to compute a ´one-over´ function are presented. This circuit capitalises on the linear region operation of an MOS transistor. Nonlinearity is found to be primarily produced by mobility degradation, but is easily cancelled. The circuit requires limited component matching and it operates with 8 bit accuracy for a wide input and output range.