Patent ID: 8922300
Filing Date: 2014-12-30
Classification: H03H

Abstract:
1. A filter circuit, comprising: a first I/O terminal; a second I/O terminal; a first capacitor having a first electrode and a second electrode, wherein the first electrode is electrically coupled to the first I/O terminal; a second capacitor having a third electrode and a fourth electrode, wherein the third electrode is electrically coupled to the second I/O terminal; a third capacitor having a fifth electrode and a sixth electrode, wherein the fifth electrode is electrically coupled to the first I/O terminal and the sixth electrode is electrically coupled to the second I/O terminal; a first inductor having a first terminal and a second terminal, wherein the first terminal is electrically coupled to the first I/O terminal and the second terminal is electrically coupled to a first reference voltage; a second inductor having a third terminal and a fourth terminal, wherein the third terminal is electrically coupled to the second I/O terminal and the fourth terminal is electrically coupled to a second reference voltage; and a third inductor having a fifth terminal and a sixth terminal, wherein the fifth terminal is electrically coupled to the second electrode and the fourth electrode, and the sixth terminal is electrically coupled to a third reference voltage, wherein the second electrode and the fourth electrode are coupled to the third reference voltage through the third inductor without passing through the second terminal and the fourth terminal; wherein the first I/O terminal is an input terminal and the second I/O terminal is an output terminal, or the second I/O terminal is an input terminal and the first I/O terminal is an output terminal; and the frequency response of the filter circuit comprises a resonant frequency, a first notch on a lower frequency side of the frequency response and a second notch on a higher frequency side of the frequency response.