A 0.4 V, $-$77.2 dBm WuRX With Digitalized Loop-Calibration and Temperature-Compensation

This article introduces ultralow power, high sensitivity, and wide temperature range wake-up receiver (WuRX) for wireless sensor networks (WSNs). A digitalized global calibration loop (DGCL) is proposed for the differential WuRX to remove the global offsets and avoid the degradation in sensitivity. Moreover, this article proposes a digital temperature compensation (DTC) with a gate leakage-based sensor, improving the sensitivity and robustness of the WuRX in a wide temperature range with a low-power consumption. The proposed WuRX is implemented in a 65 nm LP CMOS process, occupying an active area of 0.3 mm <tex-math notation="LaTeX">²</tex-math> . Operating at 915 MHz, it has a <tex-math notation="LaTeX">$-$</tex-math> 77.2 dBm sensitivity at 100 bps while consuming 5.24 nW from 0.4 V supply voltage. When the temperature changes from <tex-math notation="LaTeX">$-$</tex-math> 30 <tex-math notation="LaTeX">∘</tex-math> C to 70 <tex-math notation="LaTeX">∘</tex-math> C, the <tex-math notation="LaTeX">$S11$</tex-math> variation is reduced by 67% due to the presence of DTC.