Scientific Research Publishing
The authors demonstrate the design of a novel Voltage-Controlled Oscillator (VCO), which is based on a Metal-Oxide Semiconductor Field Effect Transistor (MOSFET) differential amplifier with active load. This VCO achieves low phase noise and wide tuning range. The phase noise is -120dBc/Hz at 600KHz offset from a 1.216GHz carrier frequency. This value is comparable to that of a LC-based integrated oscillator. The operating frequency can be tuned from 117MHz to 1.216GHz with the supply voltage varying from 1.3V to 3.3V. Therefore, the tuning range is about 90.38% which is larger than most of the LC and ring oscillator.