Patent ID: 9559735
Date: 2017-01-31
CPC Classifications: H03F,H03H,H04B

Claim:
1. A circuit comprising: a first resonant switching circuit having a first terminal coupled to a first output terminal of a low noise amplifier to receive an RF signal; a second resonant switching circuit having a first terminal coupled to the first output terminal of the low noise amplifier; a third resonant switching circuit having a first terminal coupled to a second terminal of the first resonant switching circuit, wherein the first resonant switching circuit is configured to produce a low impedance at a carrier frequency of the RF signal and a high impedance at a first frequency, wherein the second resonant switching circuit and the third resonant switching circuit are configured to produce a high impedance at the carrier frequency of the RF signal and a low impedance at the first frequency, wherein the first resonant switching circuit, the second resonant switching circuit, and the third resonant switching circuit are M-path circuits, wherein the M-path circuits comprise an in-phase switched capacitor circuit and a quadrature switched capacitor circuit, and wherein the in-phase switched capacitor circuit is selectively coupled to the quadrature switched capacitor circuit by a first transconductance circuit and the quadrature switched capacitor circuit is selectively coupled to the in-phase switched capacitor circuit by a second transconductance circuit.