3.3GHz DCO with a frequency resolution of 150Hz for All-digital PLL

A 3.3 GHz DCO that achieves a minimum frequency quantization step of 150 Hz without any dithering is presented. The fine digital tuning is obtained through a capacitive degeneration of a portion of the transistor switching pair used in a classical LC-tank oscillator. The DCO exhibits a phase noise of -127.5 dBc/Hz@1 MHz drawing 16 mA from a 1.8 V supply, resulting in an FoM of 183 dBc/Hz. The active area is 700 ¿m × 450 ¿m.