A 140 mV Self-Starting 10 mW DC/DC Converter for Powering Low-Power Electronic Devices from Low-Voltage Microbial Fuel Cells

This paper presents an original self-starting DC/DC converter for low-power and low-voltage applications such as energy harvesting from microbial fuel cells to supply low-power electronic devices. Design is performed according to specifications issued from the stringent characteristics of microbial fuel cells. The harvested power reaches 10 mW under 0.3 V input voltage for the ten 1.3-liter experimental microbial fuel cells connected in parallel. The converter is adapted from a boost topology. It includes a self-oscillating sub-circuit for autonomous operation and a simple analog input-voltage control to harvest maximum energy from the source. The paper presents experimental results from a discrete and low-cost prototype. A global efficiency of more than 73% is achieved for 0.3 V input-voltage and under realistic harvesting conditions for the MFCs and the converter prototype.