Fully CMOS integrated active rectifier without voltage drop

This paper presents measurement results of an active rectifier with negligible voltage drop. The rectifier is fully integrated using a standard CMOS process (AMS C35) without special process options. It can be separated into a first passive stage and a second active stage. The second stage consists of a comparator which drives a PMOS switch. The target application is a telemetric power supply in the 125 kHz ISM band with input voltages between 1.25 and 3.75 V. Nevertheless, the maximum frequency range is between several Hz up to over 2.5 MHz @ 3.5 V input amplitude.