A low-power, temperature and supply voltage compensated current starved ring oscillator

A low-power, 3.82 MHz oscillator based on a feedback loop is presented. The oscillator does not need a stable current reference to obtain a stable frequency independent of voltage and temperature variations because of the usage of negative feedback. The frequency variation, in the temperature range from −20 °C to 80 °C, is±0.6% and it depends only on the temperature coefficient of the resistor R, while the reference current variations are −11%/+25% in the same temperature range. The oscillator power consumption is 5.1μW and the active area is 0.09 mm2. The proposed oscillator is implemented in a 0.18μm CMOS process and the simulation results are shown.