A Design of a Continuous-Time CMOS Low-Pass Filter Using FG-MOSFET Fully-Differential Current-Mode Integrators and Its Analysis

Abstract

This paper presents a design of a continuous-time CMOS low-pass filter using floating-gate MOSFET (FG-MOSFET) integrators. In this design, FG-MOSFETs were used to realize fully-differential current-mode integrators which can operate at a low supply voltage of 1.5V. The analysis has been carried out on the filter performances as well as on integrator's bias conditions, operating frequency range, gain, harmonic distor-tion, and Q-enliancement technique. HSPICE simulations showed that the proposed method can realize a low-voltage/low-power continuous-time fully-differential current-mode CMOS filter usable in the frequency range up to several tens of megahertz. The proposed filter is suitable to low-voltage mixed-signal VLSIs, because it can be fabricated by a standard double-poly CMOS process.