Micropower Clock Generator Circuit Using an Optimized Band-Gap Reference for Energy Harvesting Charge Pumps

Abstract

In recent years, a lot of research and effort have been developed in micro-scale energy harvesting (EHV) for Wireless Sensor Networks (WSN) because of their viable and promising approach for self powering low voltage circuit. The key element in such an application is the charge pump circuit as a power converter. A charge pump (CP) driven by tow pumping clocks, is introduced to generate voltages beyond the supply voltage range. In this paper, a clock circuit for a charge pump was proposed. This circuit was achieved using tow components: a Voltage Control Ring Oscillator (VCOR) as a clock generator and a Band-Gap Reference (BGR) as a voltage reference. The circuit was implemented using 0.35 µm CMOS process, and was generated the desired pumping clocks signals at tens of Mhz under just 9.6 µW for a power supply of only 1V.