A High Voltage Self-Biased Integrated DC-DC Buck Converter With Fully Analog MPPT Algorithm for Electrostatic Energy Harvesters

This paper presents a high voltage and low power inductive DC-DC buck converter for interfacing electrostatic energy harvesters. The system, implemented in TSMC 0.25 µm BCD, can convert input voltages from 5 to 60 V to recharge the energy storage system connected to the output. The system includes also a Maximum Power Point Tracking algorithm for matching the equivalent source resistance of harvester and AC-DC converter. Due to power consumption constrains, a conventional implementation of this algorithm, based on ADC, DAC and complex digital processing is replaced by a much simpler fully analog design. Measurements have shown a peak end-to-end efficiency of 88% with 99.8% MPPT peak efficiency.