A 14.4nW 122KHz dual-phase current-mode relaxation oscillator for near-zero-power sensors

This paper presents a novel ultra-low-power dual-phase current-mode relaxation oscillator, which produces a 122 kHz digital clock and has total power consumption of 14.4 nW at 0.6 V. Its frequency dependence is 327 ppm/°C over a temperature range of −20° C to 100° C, and its supply voltage coefficient is ±3.0%/V from 0.6 V to 1.8 V. The proposed oscillator is fabricated in 0.18 μm CMOS technology and occupies 0.03 mm². At room temperature it achieves a figure of merit of 120 pW/kHz, making it one of the most efficient relaxation oscillators reported to date.