325 nA quiescent – cold-start from micro-watt sources
The BQ25505RGRT is an energy-harvesting PMIC from Texas Instruments designed to extract usable power from low-voltage, low-current sources. Its 325 nA typical supply current sets the floor for the minimum source power the boost converter can cold-start from — a photovoltaic cell delivering tens of micro-watts under dim indoor light is enough to begin charging. The input operates from 0.12 V up to 4 V, covering the typical open-circuit voltage of a single solar cell or thermoelectric generator (TEG). The controller manages the energy storage element — a rechargeable battery or supercapacitor — while protecting against over-voltage on the storage node.