Switchable gain amplifier having a high-pass filter pole

摘要

The present invention provides a switchable gain amplifier comprising a high-pass filter pole. The switchable gain amplifier comprises first and second input nodes for receiving first and second components of a differential input signal. A first input terminal of a first differential amplifier is coupled to the first input node, and a first input terminal of a second differential amplifier is coupled to the second input node. A first variable resistance is coupled between the first input terminal of the first differential amplifier and a second input terminal of the first differential amplifier. A second variable resistance is coupled between the first input terminal of the second differential amplifier and a second input terminal of the second differential amplifier. A differential capacitor is coupled between the second input terminal of the first differential amplifier and the second input terminal of the second differential amplifier.