Patent ID: 6304135
Filing Date: 2001-10-16
Classification: H03H

Abstract:
A method of tuning a G.sub.m /C filter having a transconductive G.sub.m stage and a variable output capacitor, said variable output capacitor having a variable current source, and a first and second circuit portion, said first circuit portion comprises a plurality of transistors coupled to a plurality of switches, said transistors coupled to said variable current source, said transistors and switches coupled to a calibration capacitor, said second circuit portion having an algorithm for iteratively selecting said transistors and switches to tune said G.sub.m /C filter, said method comprising the steps of:calibrating said calibration capacitor iteratively with said variable current source to tune said G.sub.m /C filter;powering off said first and second circuit portions after said calibration step; andtuning said calibration capacitor to vary the capacitance of said variable output capacitor with said variable current source.