A LOW POWER PUSH-PUSH DIFFERENTIAL VCO USING CURRENT-REUSE CIRCUIT DESIGN TECHNIQUE

Abstract

This paper presents a complementary metal-oxide- semiconductor (CMOS) difierential voltage-controlled oscillator (VCO) implemented with the push-push principle. The push-push VCO uses two frequency doublers stacked in series with an LC quadrature voltage-controlled oscillator (QVCO) to share the dc current with the QVCO for low power consumption. The proposed CMOS VCO has been implemented with the TSMC 0.18m CMOS technology, and the die area is 0:822£1:564mm 2 . At the supply voltage of 0.9V, the total power consumption is 3.15mW. The free-running frequency of VCO is tunable from 10GHz to 11.15GHz as the tuning voltage is varied from 0.0V to 1.2V. The measured phase noise at 1MHz frequency ofiset is i114:93dBc/Hz at the oscillation frequency of 9.99GHz, and the flgure of merit (FOM) of the proposed VCO is i190:0dBc/Hz.