A First Dual-Mode RF Fully Digitally Controlled Oscillator in 0.13μm CMOS

The first CMOS based fully digitally controlled oscillator suitable for GSM/EDGE and UMTS transmitter is presented. Drawing an extremely low current in order to achieve the phase noise performance sufficient for both communication systems it is highly suitable for terminal applications. A coarse tuning range from 3.25 to 4.25 GHz is achieved by a combination of binary weighted and thermometer coded switchable capacitors which allow a maximum frequency step of 250 KHz. The low current consumption and the excellent phase noise performances achieved make this topology attractive for multi mode systems. A complete implementation in 0.13 μm CMOS technology is here presented