An energy harvester circuit operates to harvest energy in battery-less electrical apparatus. The circuit includes a string of capacitors coupled to a circuit input to receive energy to be harvested. A string of transistors are coupled as pumping transistors to respective ones of the capacitors in the string of capacitors. A compensation coupling circuit is coupled between each transistor in the string of pumping transistors and one of a subsequent or a preceding transistor in the string of pumping transistors.