A Widlar-bandgap based intermediate-frequency voltage-controlled oscillator for GSM/DCS transceiver ICs

This paper presents an intermediate-frequency voltage-controlled oscillator using a Widlar-bandgap for stable operation over supply and temperature variations without degrading the phase noise performance. The design is fabricated in a 0.35 /spl mu/m SOI BiCMOS process and is packaged in a QFN24 plastic package. The VCO operates at 1 GHz with a tuning range of 250 MHz and achieves a phase noise of -113 dBc/Hz at 400 kHz offset from the carrier. The VCO core and buffer consume 4 mA and 11 mA from a 2.7 V power supply, respectively. The IF-VCO is suitable for GSM/DCS transceiver IC applications.