An efficient power management unit for μWatt thermoelectric generators

This paper presents an efficient power management unit (PMU) that supports μWatt load range for TEG-based applications. The PMU consists of an inductor-based DC-DC converter that boosts a small TEG voltage and followed by two switched capacitor-based buck converters which are used to drive a μWatt-SoC. The PMU generates a regulated 1.1V and 0.6V output voltages. Pulse frequency modulation scheme is utilized to regulate the output voltages. SPICE simulation results in 65nm CMOS technology show that the maximum end-to-end efficiency of the PMU is 68% at an output power of 62μWatt. The PMU occupies an area of less than 0.9mm². The switched capacitor circuit enables the usage of dynamic voltage scaling (DVS) that helps the PMU to operate in ultra-low power modes.