A Single-Input Four-Output (SIFO) AC–DC Rectifying System for Vibration Energy Harvesting

An ac-dc rectifying system for vibration energy harvesting is proposed to generate outputs of four different voltage levels with a single power source. The proposed dual-output rectifier uses only four diodes, similar to a conventional single-output full-bridge rectifier. A switched-capacitor down-converter provides two output voltages from a single input from the voltage doubler by using the proposed load balancer with a low design complexity. The proposed system is implemented in a 0.35-μm CMOS process, and it occupies an area of 0.143 mm 2 .