Implementation of DC-DC PFM Boost Power Converter for Low-power Energy Harvesting Applications

Abstract

This paper implements a low-power PFM boost power converter that can be applied to low-voltage energy harvesting systems, such as in the IoT intelligent micro-sensing power module or energy harvesting interface circuit. The interface circuit can provide power management functions between the energy harvesting device and the electric load. The power converter uses the PFM feedback control mechanism to implement a boost converter which can stabilize the output voltage when the input voltage and load change. And when the input voltage of the PFM boost power converter circuit is less than the transition voltage of the Schmitt triggered inverter circuit, the PFM control circuit of the power converter will stop operating the feedback control regulation process, and the boost power converter will enter the standby mode. Therefore, the static power consumption of the boost power converter is minimized. The overall circuit is simulated and designed using TSMC 0.35um 2P4M CMOS process technology. The converter having 0.324x0.43015 mm2 chip size and power dissipation about 2.287mW. This chip can operate with input supply voltage from 2.0V to 2.5V, and its output voltage can stable at 3.0V and less than 20mV ripple voltage at maximum output current 10mA. The converter with a load regulation is less than 0.944mV/mA and the line voltage regulation is less than 34.6mV/V.