A continuous-time current-mode integrator

The authors propose a continuous-time current-mode integrator that offers potential advantages for both higher frequency and lower power monolithic filtering applications. Owing to the small voltage swings inherent in current-mode circuits, the integrator time constant is determined by a small-signal transconductance and an additional MOSFET gate capacitance, while good linearity is maintained using a standard 2- mu m digital CMOS technology. Simulation results predict passband cutoff frequencies exceeding 30 MHz for a five-pole low-pass filter dissipating as little as 2 mW/pole with a 5-V power supply.>