Wake-Up Oscillators with pW Power Consumption in Dynamic Leakage Suppression Logic

In this paper, two circuit topologies of pW-power Hz-range wake-up oscillators for sensor node applications are presented. The proposed circuits are based on standard cells utilizing the Dynamic Leakage Suppression logic style [4]–[5]. The proposed oscillators exhibit low supply voltage sensitivity over a wide supply voltage range, from nominal voltage down to the deep sub-threshold region (i.e., 0.3 V). This enables direct powering from energy harvesters or batteries through their whole discharge cycle, suppressing the need for voltage regulation. Post-layout time-domain simulations of the proposed oscillators in 180nm show a power consumption of 1.4–1.7pW, a supply-sensitivity of 55–40%/V over the 0.3V–1.8V supply voltage range, and a compact area down to 1,500µm2. The very low power consumption makes the proposed circuits very well suited for energy-harvested systems-on-chip for Internet of Things applications.

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