Wide-frequency-range low-power variable-length ring oscillator in UMC CMOS 0.18 µm

The paper describes structure and simulation results of the novel ring oscillator designed in UMC CMOS 0.18 μm (1.8 V). Frequency generated by the oscillator is tuned by scaling the supply voltage, additionally ring length is digitally controlled. Presented ring oscillator has very wide tuning range (250 MHz-2.1 GHz) with small current consumption (34-689 μA).