A 22.3-nW, 4.55 cm 2 Temperature-Robust Wake-Up Receiver Achieving a Sensitivity of − 69.5 dBm at 9 GHz Haowei Jiang , Student Member , IEEE, Po-Han

Abstract

This article presents a miniaturized wake-up receiver (WuRX) that is temperature-compensated yet still consumes only 22.3 nW (7.3 nW excluding the temperature- compensation blocks) while operating at 9 GHz ( X-band). By moving the carrier frequency to 9 GHz and designing a high impedance, passive envelope detector (ED), the transformer size is reduced to 0.02 cm 2 while still achieving 13.5 dB of passive RF voltage gain. To further reduce the area, a global common- mode feedback (CMFB) technique is utilized across the ED and baseband (BB) amplifier that e liminates the need for off-chip ac-coupling components. Multiple temperature-compensation techniques are proposed to maintain constant bandwidth of the signal path and constant clock frequency. The WuRX was implemented in 65- (RF) and 180-nm (BB) CMOS and achieves −69.5- and −64-dBm sensitivity with and without an antenna, respectively. Importantly, the sensitivity is demonstrated to vary by only 3 dB from −10 to 40 ◦C. This article demonstrates state- of-the-art performance for WuRXs operating at >1 GHz while achieving the smallest area and best temperature insensitivity.