Innovation of Switched-Capacitor Voltage Multiplier Part 1: A brief history T he switched-capacitor (SC) voltage multiplier is becoming one of the most critical IC blocks for energy harvesting in wireless sensor nodes to generate a voltage high enough for microwatt sensing and computing ICs in a nanometer complementary metal-oxide-semiconductor (CMOS) from environmental energy sources such as mechanical vibration, electromagnetic wave, and temperature gradient. However, its origin was a 10 m-scale particle accelerator generating 1 MV back to 1920s. There have been several innovative design techniques to realize integrated SC voltage multipliers since the original one. This article overviews such innovations for the last century and describes how 10 m-scale SC voltage multipliers have been integrated in microwatt ICs and what technical considerations are critical for area- and power-efficient design. It also summarizes how device parameters determine circuit Digital Object Identifier 10.1109/MSSC.2015.2495678 Date of publication: 21 January 2016 1943-0582/16©2016IEEE IEEE SOLID-STATE CIRCUITS MAGAZINE W I N T E R 2 0 16 51 image licensed by graphic stock Toru Tanzawa