A 5.9 GHz Low Power and Wide Tuning Range CMOS Current-controlled Ring Oscillator

Designing low power, low noise, wide tuning range and small size circuit in one single chip is very challenging. This paper describe a low power, wide tuning range three-stage current-controlled ring oscillator (CCO) designed on 0.18um CMOS technology. The CCO circuit has tuning range from 251 MHz to 5.5 GHz or 183% wide. It consumes only 144 uA to 9.76mA by using 1.8V power supply. Phase noise is -104 dBc /Hz at 5.5 GHz and 4 Mhz offset frequency. Calculated FoM is -154.4 dBc /Hz which is the best among published counterpart papers. The size of the core oscillator circuits without bonding pads is only 0.0003 mm2.