An Integrated Circuit of A Cold Start-up Circuit for A Thermoelectric Energy Harvesting System

A cold start-up circuit for thermoelectric energy harvesting systems is presented in this paper. The proposed cold start-up circuit shares the energy harvesting inductor and load capacitor with the main boost converter, so no extra off-chip components are required, resulting in a small form factor. The start-up circuit comprises a stacked ring oscillator, a pair of low-voltage charge pumps, a low-power voltage detector, a reset switch, and two power switches. A prototyped chip for concept proving is designed and fabricated in a
$0.18\ \mu \mathrm{m}$
CMOS process. The measured waveforms demonstrate that the prototyped cold start-up chip can boost an input voltage of 300mV up to 1V within 950ms when the loading capacitance is
$0.1\ \mu \mathrm{F}$
.