Super-Cutoff Analog Building Blocks for pW/Stage Operation and Demonstration of 78-pW Battery-Less Light-Harvested Wake-Up Receiver down to Moonlight

Techniques to lower power in analog and sensor interfaces well below regular transistor leakage $(\mathrm{V}_{\mathrm{G}\mathrm{S}}=0\mathrm{V})$ are introduced. The proposed circuit techniques enable $\sim$pW power in super-cutoff $(\mathrm{V}_{\mathrm{G}\mathrm{S}}\lt 0\mathrm{V})$ building blocks from current mirrors to OTAs, pseudo-resistors and bias. A LiFi optical wake-up receiver with 78-pW power is demonstrated with continuous operation solely powered by an unregulated 1-mm2 solar cell down to llux (moonlight).