Flicker Noise Improved CMOS Mixer Using Feedback Current Bleeding

A CMOS mixer using a negative-feedback current-bleeding circuit is presented with low flicker noise and robustness to process-voltage-temperature variations. The proposed technique reduces the common-mode flicker noise generated by the RF transconductance stage and the current-bleeding circuit, thus reducing conversion to the differential-mode flicker noise caused by mismatch and process variations. In addition, the proposed technique achieves stability against the voltage and temperature variations due to the negative feedback. Measurement results show a voltage conversion gain of 19 dB, an IIP3 of -7 dBm, and a flicker-noise figure of 14.2 dB at 10 kHz. The proposed mixer dissipates 3 mW from a 1.3 V supply voltage.