Patent ID: 8260235

Claim:
Down conversion circuitry comprising: a post mixer amplifier adapted to receive and amplify a signal based on a down converted receive signal to provide a post mixer amplified signal, such that: a gain of the post mixer amplifier is based on an automatic gain control (AGC) signal; during a normal operation mode, the down converted receive signal is based on down conversion of a radio frequency (RF) receive signal; and during a calibration mode, the down converted receive signal is representative of a direct current (DC) offset of an RF mixer; a DC correction amplifier adapted to apply a DC correction to the post mixer amplified signal based on a DC correction signal to provide a post mixer corrected signal; and control circuitry adapted to: select between the normal operation mode and the calibration mode; provide the AGC signal and the DC correction signal; during the calibration mode, select at least two gain levels of the post mixer amplifier via the AGC signal and determine corresponding calibration DC corrections that drive the post mixer corrected signal to about zero; during the normal operation mode, select a desired gain of the post mixer amplifier via the AGC signal, determine the DC correction based on the calibration DC corrections and the desired gain, and provide the DC correction via the DC correction signal.