2016 Volume 13 Issue 11 Pages 20160373
This paper presents a 1∼3 GHz voltage controlled oscillator (VCO) with a rail-to-rail VCO tuning voltage (VCONT) range. To obtain wide and linear VCONT range, a new differential amplifier with a rail-to-rail common mode input range and an unstacked output stage is proposed. By using the proposed differential amplifier in the analog fine tuning block, VCONT can span almost the rail-to-rail supply voltage with good linearity. For verification, a prototype VCO was fabricated in a 65 nm 1P7M CMOS process.