A High Frequency Piezo-Electric Oscillator with Negative Resistance Enhancement Circuit

Abstract

We have proposed a new piezoelectric oscillator circuit suitable for use in frequency range between 100 MHz and 1.24GHz. The proposed oscillator is composed of a colpitts oscillator and a two-stage common-emitter amplifier. The amplifier picks up the signal from the emitter of the oscillator transistor and feeds back the amplified signal to the base of the oscillator transistor with adequate phase shift. Simulation has shown that sufficiently large negative resistance can be obtained compared to the usual colpitts oscillator at 311MHz, 622MHz, 933MHz and 1.24GHz.