A 2.5mW 900MHz Receiver Employing Multiband Feedback with Bias Current Reuse

A down-conversion receiver that employs a merged IF-amplifier and mixer is described. Down-converted signal at IF is fed back into the mixer transconductor for further amplification. The receiver operates at a nominal supply voltage of 1.2 V with a current requirement of 2.1 mA and provides a peak conversion-gain of 55 dB. The SSB noise figure is 13 dB at an IF of 1 MHz and 9.8 dB at an IF of 4 MHz. The receiver is implemented in a 0.13-mum CMOS process, with a core area of less than 0.1 mm².