Boost Converter with a Start-Up Strategy of Sharing Main Power NMOS for Scalable Cotton-Yarn-Based Battery

This paper presents a low-power boost converter for energy harvesting from a scalable cotton-yarn-based battery. The proposed converter can start up at 700mV. Compared with other start-up strategies, a start-up strategy of sharing the main power NMOS without a start-up transistor is adopted to reduce the chip area. The input voltage range of the converter can reach 4.2V and the output range is 1.8V-5V. The proposed converter is implemented in 0.18 μm BCD process. And the chip area is 616μm × 417μm, which is 4.6% less than using a start-up transistor.