2.4 Ghz Quadrature Differential Lc Oscillator Using Two Coupling Capacitors

摘要

A new circuit topology for quadrature signal generation is presented and demonstrated on a 2.4-GHz CMOS differential oscillator. In the proposed circuit two identical negative-resistance oscillators are coupled to each other via two capacitors in such a way that quadrature differential signals are generated. Since capacitor is used as coupling device, the proposed circuit has the advantage that no extra noise sources and power consumption are introduced to the circuit in the coupling process. Simulation results are presented for circuits designed with CMOS technology. The oscillator has a phase noise of -98.96 and -124.1dBc/Hzat 100 KHz and 1 MHz from the carrier, respectively. The circuit draws 6.4mA from a 1.6-V supply.