Sub-30 ppm/°C High-frequency Temperature-compensated CMOS Relaxation Oscillator

This paper describes the design and realization of a high-frequency temperature-compensated CMOS relaxation oscillator in a 0.35-μm CMOS technology. The proposed oscillator employs the current-controlled topology with a resistive source-degeneration transconductor and a current comparator in order to achieve high oscillation frequency and low power dissipation. Temperature compensation of the oscillation frequency is achieved by simulation results show that, at a nominal oscillation frequency of 32.48 MHz, the proposed oscillator exhibited a temperature coefficient of less than 28.41 ppm/oC over a temperature range of -40 °C to +120 °C, while consuming 241.5 μW from a 2.5-V single power supply voltage.