A fully integrated CMOS RF front-end with on-chip VCO for W-CDMA applications

Abstract

A fully integrated RF front-end for W-CDMA applications including a low noise amplifier, a down conversion mixer, a digitally programmable gain amplifier. an on-chip VCO, and a fractional-N frequency synthesizer is designed using a 0.35-mum CMOS process. A multi-stage ring shaped on-chip LC-VCO exhibiting bandpass characteristics overcomes the limitation of low-Q components in the tank circuits and improves the phase noise performance. The measured phase noise of the on-chip VCO is -134 dBc/Hz at I MHz offset. The receiver RF front-end achieves a NF of 3.5 dB, an IIP3 of -16dBm, and a maximum gain of 80 dB. The receiver consumes 52 mA with a 3-V supply and occupies only 2 mm(2) die area with minimal external components.