A 3µW fully-differential RF envelope detector for ultra-low power receivers

A fully differential envelope detector (ED) operating at 2.4GHz is designed in 90nm CMOS technology. The new design uses the common-gate topology to deal with large common-mode input signals through first-order current cancellation. Thereby, a fully differential ultra-low power super-regenerative front-end is enabled. It has a measured output voltage swing of 2.8–127mV and achieves 19.6dB output SNR at sensitivity input level. The circuit consumes 3µW from a 1.2V power supply.