Design of RF to DC converter in 90nm CMOS technology for ultra-low power application

This paper presents an RF to DC converter circuit design implemented and simulated in 90nm 1P9M CMOS process technology. The system employs a voltage rectifier that converts a very low RF signal of up to -2.4dBm into a useable DC voltage. The converted DC voltage was stored in a battery with a protection circuit. The battery was then used as a supply voltage of the low dropout (LDO) regulator which is composed of a bandgap voltage reference circuit with an output voltage of 0.5V and an error amplifier with a gain of 74.9dB and phase margin of 62° that provides a stable system performance. The system yields a regulated output voltage of 0.9V.