A low power consumption, low phase noise, and wide tuning range LC VCO with ACC

A 4.8GHz LC voltage controlled oscillator (VCO) for WSN Applications is designed based on TSMC 0.18 µm RF CMOS process. The VCO adopts complementary differential negative resistance structure with switch resistor biasing which achieves good phase noise performance and realizing low power consumption. The 3-bit switch capacitor array provides wide tuning range and the 6-bit switch resistors array provides varied biasing current by auto current calibration (ACC) circuit. With a 1.8V supply voltage, the post-simulated result achieves 27.7% tuning range that can compensate the frequency deviation due to process corners. The post simulated phase noise is −119dBc/Hz@1MHz at frequency of 2.44GHz. The operating current of the VCO core is from 0.4mA to 3.3mA. Finally, the chip size of the VCO core is 0.3mm ² and the whole chip size is 0.8×1.2mm ² with testing buffer and pads.