Analysis of the Rectifier Circuit Valid Down to Its Low-Voltage Limit

This paper describes a simple analytical model of the rectifier circuit valid down to very low voltage operation (input voltage below the thermal voltage). Steady-state and transient analyses of the rectifier with the diode described by an exponential I-V characteristic are presented. We provide formulas for the dc output voltage level, the output voltage ripple, and the power conversion efficiency. We also give a compact expression for the charging time of the load capacitor. The models of the rectifier and the voltage doubler for input voltages down to the thermal voltage are verified with simulations and measurements using circuits built with off-the-shelf 1N4148 diodes.