Wide-Band CMOS Circuit Design Techniques for RF Amplifier and Ring VCO

RF CMOS circuit design techniques for ultrawideband (UWD) applications are presented. In the RF amplifier design, a combination of a constant-k filter and a resistive shunt feedback circuit is suggested for wide-band operation. We report that a circuit integrated by using 0.13-mum CMOS process technology has achieved an operation bandwidth from 2 to 5.8 GHz with a peak gain of 9 dB. In a ring VCO, a frequency tuning technique that controls the load resistance of the inverter instead of conventional current controlling, has been successfully used to oscillate from 1.8 to 7 GHz.