Abstract:
A body-coupled symmetric wakeup transceiver is proposed for always-on device discovery in IoT applications requiring security and low-power consumption. The wakeup transceiver (WTRx) is implemented in 65nm CMOS, using digital logic cells and operates at 0.6V. A directly-modulated open-loop DCO generates an OOK-modulated 10MHz carrier, with a frequency-locked loop for intermittent calibration. A passive receiver incorporates a digital IO cell as hysteretic comparator, with a two-phase correlator bank. A novel MAC scheme allows for duty-cycling in both transmitter and receiver. Measured power consumption is 3.54μW, with sensitivity of 88mV and maximum wakeup latency of 150ms.