Patent ID: 7957716
Filing Date: 2011-06-07
Classification: H03H,H04B

Abstract:
1. A baseband filter having a baseband filter input node and a baseband filter output node, the baseband filter comprising: an operational amplifier (op-amp) having a first op-amp input terminal, a second op-amp input terminal, and an op-amp output terminal, wherein the op-amp is adapted to produce, at the op-amp output terminal, an amplified signal that includes noise gain produced by the op-amp; a first pole circuit having a first pole circuit input node and a first pole circuit output node, wherein the first pole circuit input node is electrically coupled with the op-amp output terminal, and the first pole circuit is adapted to receive the amplified signal and to attenuate the noise gain to produce a filtered, amplified signal at the first pole circuit output node; a first feedback capacitor having a first terminal and a second terminal, wherein the first feedback capacitor is electrically coupled between the first pole circuit and the first op-amp input terminal, and is adapted to compensate for a phase shift produced by the first pole circuit; and an active device having an input node and an output node, wherein the input node of the active device is electrically coupled with the first pole circuit output node, and the output node of the active device is electrically coupled with the baseband filter output node, and wherein the active device is adapted to amplify the filtered, amplified signal and to produce a baseband filter output signal at the output node of the active device.