Design of very low voltage CMOS rectifier circuits

This paper presents a simple analytical model of the basic rectifier circuit for very low voltage operation based on the Shockley (exponential) law of the diode. The main alternatives for the implementation of diodes in CMOS technologies and the calculation of the equivalent diode parameters for low voltage operation are summarized. The model of the half-wave rectifier for very low voltage is verified with measurements on a circuit built with a 1N4148 diode. The main diode implementations using MOS transistors of a 0.13 μm technology operating in weak inversion are analyzed and a very simple design procedure is suggested.