A 7–8.5 GHz LC Voltage-Controlled Oscillator with –111.7 dBc/Hz Phase Noise at 1-MHz offset for Ultra-Low-Jitter Phase-Locked Loop

Abstract

This work presents an area efficiency LC voltage-controlled oscillator for an ultra-low-jitter phase-locked loop. Using a 3-turn area-compact spiral, the VCO achieve area-efficient without degrading LC-tank quality factor. The negative transconductance cell was NMOS type so that the start-up was done in 3ns. This work also includes a tail inductor for the noise filtering. As a result, the measured phase noise at 8 GHz was -111.7 dBc/Hz with 1 MHz offset and -134.9 dBc/Hz with 10 MHz offset. The power consumption was only 2.7 mW at 8 GHz. Also, the die area was less than 0.03 mm2.