A novel square root domain lossless integrator and its application to KHN biquad filter design

In this paper, a novel square root domain lossless integrator and its application to KHN (Kerwin-Huelsman-Newcomb) biquad are proposed. The presented lossless integrator based on quadratic characteristics of MOS transistor was designed by using state space method. It consists of a geometric mean circuit, a current mirror and a capacitor. The scaling factor of the integrator is electronically tuneable by an external bias current. The KHN biquad consists of two lossless integrator blocks and a summer circuit. The summer circuit is developed by using linear transconductors. KHN biquad filter was simulated by using SPICE simulation program, simulation results are good in agreement with the theoretical analysis.