Amplifier with integral notch filter

摘要

An amplifier is disclosed that may include a filter, such as a notch-filter, to filter an output signal provided by the amplifier. The included filter may suppress and/or reduce a gain of the amplifier for a particular range of frequencies. In one embodiment, a frequency response of the filter may be determined by one or more reactive components included within the amplifier. In at least one embodiment, the amplifier may include two or more mutual inductors to reduce the gain of the amplifier when operated at or near a predetermined frequency. In another embodiment, the amplifier may include one or more variable capacitors that may enable the frequency response of the filter to be changed and/or modified.

主权项

1. A configurable amplifier, comprising:
a first resonant circuit to provide a low impedance circuit path to reduce a gain of the configurable amplifier when operating near a first frequency, the first resonant circuit comprising:
a first parasitic capacitor coupled between a drain terminal of a first transistor and a body terminal of the first transistor;a first inductor coupled between the body terminal of the first transistor and ground; anda second inductor to couple with the first inductor to reduce the gain of the configurable amplifier.