Patent ID: 7113029
Filing Date: 2006-09-26
Classification: H03H

Abstract:
1. A transconductance filter circuit, comprising: a transconductor comprising two inputs for receiving two differential voltages, and a first output terminal and a second output terminal for outputting two differential signals; a first capacitor array comprising at least one first switch capacitor unit controlled by a first signal comprising a most significant bit and omitting a least significant bit of a control signal, and a plurality of first capacitors coupled between the first output terminal and the second output terminal and have a first equivalent capacitance when the first signal is enabled; and two second capacitor arrays, each second capacitor array comprising at least one second switch capacitor unit controlled by a second signal comprising the least significant bit and omitting the most significant bit of the control signal, and a plurality of second capacitors, wherein the second capacitors of the two second capacitor arrays are respectively coupled between the first output terminal and a ground level, and between the second output terminal and the ground level, and have a second equivalent capacitance when the second capacitors of the two second capacitor arrays are coupled in serial and the second signal is enabled, wherein the first equivalent capacitance exceeds that of the second equivalent capacitance.