Balanced frequency mixer circuit

摘要

A frequency mixer circuit includes a mixer, a load stage, and again stage. The load stage cooperates with the mixer to generate a differential output voltage signal with a mixed frequency according to a differential local oscillator voltage signal and a differential input voltage signal. The gain stage has a transconductance, and a magnitude of the differential current signal and the transconductance have a positive relationship therebetween, so as to result in a positive relationship between the transconductance and a conversion gain which is a ratio of magnitude of the differential output voltage signal to magnitude of the differential input voltage signal.

主权项

1. A frequency mixer circuit comprising:
a mixer configured to receive a differential local oscillator (LO) voltage signal with a LO frequency, and a differential input voltage signal with an input frequency, and configured to generate a differential current signal having a mixed frequency associated with the LO frequency and the input frequency; a load stage having an impedance, coupled to said mixer for receiving the differential current signal therefrom, and cooperating with said mixer to generate, based upon the differential current signal and the impedance of said load stage, a differential output voltage signal with the mixed frequency, wherein a ratio of magnitude of the differential output voltage signal to magnitude of the differential input voltage signal is defined as a conversion gain; and a gain stage coupled to said mixer, having a first transconductance, and configured such that a magnitude of the differential current signal and the first transconductance have a positive relationship therebetween, so as to result in a positive relationship between the conversion gain and the first transconductance.