A 1.2V, 0.25%/V, 50ppm/°C, 1% Precision, 500kHz Relaxation Oscillator in 55nm CMOS

This paper presents a Wide Supply Range, Low Voltage and Low Power 500 kHz Relaxation Oscillator designed in a 55nm technology node using only double gate, high-threshold I/Otransistors. The structure relies on an innovative low-voltage threshold-based current reference and on a matched single tran-sistor comparator which does not require any external reference voltage, being referenced on its own threshold. This threshold compensating structure has a Temperature Coefficient (TC) of 50 ppm/°C in [-20, 80]°C temperature range and 0.25 %/V supply sensitivity in [1.1, 1.3] V supply range. A digital 6-bits programmable resistor ensures a 1 % frequency precision at room temperature. The proposed structure drains a total average power of 1.7μW from the 1.2V, with 3.3nW/kHz power efficiency and 0.01 mm2 layout area.