A 65 nm CMOS Battery-Less RFID Tag Featuring Short Range Communication with Commodity WiFi

A low power integrated circuit that can communicate using commodity Wi-Fi equipment is described. It operates without the need for an external crystal because it fully integrates oscillators. The operation of the chip is enabled by an energy harvesting unit that, in combination with a supercapacitor, collects energy from 2.45 GHz ambient RF signals. The communication between external transceivers and the integrated circuit is performed by using backscattering techniques being the distance limited by the energy harvester to 1 m for an input power of -12 dBm. The chip has been designed using a $\mathbf{6 5 n m L P C M O S}$ process and achieves a power consumption of only $5 \mu \mathrm{~W}$ in the wake-up mode and $37 \mu \mathrm{~W}$ in the backscatter mode. The receiver has a sensitivity of $\mathbf{- 3 0 ~ d B m}$, enabling it to receive weak signals. This makes the integrated circuit ideal for use in low-power, energy-efficient devices that need to operate without a battery, the potential applications of this technology are significant.