MIXER WITH HIGH LINEARITY AND LOW OPERATING VOLTAGE

摘要

A mixer with high linearity and a low operating voltage is provided. The mixer includes a transconductor and a switch circuit. The transconductor receives a differential voltage signal and outputs a differential current signal accordingly. The transconductor includes a first resistor, a second resistor, a differential amplifier, a first current source and a second current source. The switch circuit includes a first switch, a second switch, a third switch, and a fourth switch. The first and second switches are coupled to a first input of the differential amplifier, while the third and fourth switches are coupled to a second input of the differential amplifier. The first and third switches are mutually coupled to provide an output of the mixer, while the second and fourth switched are mutually coupled to provide another output of the mixer. Each of the first, second, third and fourth switches determines whether to allow the differential current signal to pass through according to a differential control signal.