LOW NOISE, LOW DISTORTION GILBERT CELL MIXER WITH GAIN CONTROL, AND METHOD

摘要

The specific embodiment, includes a mixing circuit (100). The mixing circuit (100) includes Gilbert cells (102, 104, 108 and 109) and circuitry for providing automatic gain control (90) for each of the channels. The Gilbert cells (102, 104, 108 and 109) and the automatic gain control circuitry are driven by a transconductance amplifier (120) and therefore operate in a current mode. Differential digital automatic gain control signals are provided in response to a channel select signal from a digital control circuit. The circuit provides multiple IF channels which may be filtered individually.