A High-Efficiency Power Management Chip with 125mV On-Chip Cold startup achieving 91% efficiency for Thermoelectric Energy Harvesting

A Power management chip with a 125mV start-up and high efficiency for a Thermoelectrical energy generator (TEG) is presented in this paper. The implemented chip in the 180 nm BCD (Bipolar-CMOS-DMOS) technology process achieves a peak efficiency of 91%. In the startup circuit, the clock can be generated by a ring oscillator architecture using the stacked inverter, and the supply voltage of the ring oscillator can operate as low as 80 mV. In addition to the ring oscillator, there are voltage detectors, charge-pump stages, boost converter, and LDO. The 6-phase bulk-cmos charge pumps (CPs) using gate voltage boosting technique eliminate the reversion loss. To achieve higher end-to-end efficiency and maximum power point tracking (MPPT), a switch frequency calibration-based TEG voltage control scheme to reduce power consumption is proposed. The output voltage of 1.8 V and 1.6V can be generated by the energy harvesting system without LDO and with LDO.