1-V low-noise 200 MHz relaxation oscillator

This paper presents a high-frequency current-controlled relaxation oscillator designed for ultra-low voltage supply (0.9 V). The choosen relaxation oscillator topology provides both high frequency and low noise characteristic. Simulated results are verified by measurements on a full-custom integrated circuit. The tuning range extends from 1 to 180 MHz with supply current limited to 1.1 mA. At a 200 kHz off set from the oscillator frequency, the measured phase noise is-89 dBc/Hz.