A CMOS Gm-C State-Space Active Filter For High Frequences Synthesized By Intermediate Transfer Functions Method

摘要

In this paper are presented a CMOS Gm-C state-space active filter for high frequencies, in the 1μm CMOS process, synthesised using the intermediate transfer function method. The Gm transconductor has a good linearity (1% relative error for 2V_(p-p) input signals with a 5V power supply) and high DC gain (≥40 dB), combined with a large band to avoid errors in the filter characteristic. By using the intermediate transfer functions method, the active filter performances - as sensitivity and dynamic range (noise) - are optimised. The 1 MHz low-pass filter has the dynamic range grater than 70 db and the total harmonic distortion lower than -60 dB.