Low-Power PMIC with Two Hybrid Converters for TEG Application

This paper presents a low-power power management IC (PMIC) for Thermal Electric Generator (TEG) applications that includes investigation, demonstration, and comparison between two hybrid DC-DC converters. Both converters employs an input inductive step-up stage and an output switched-capacitor stage. The first converter, a 2-stage boost converter (2SBC), has a Boost stage connected in series with a switched-capacitor doubler, fully integrated with all control and regulation circuits. The second converter is an open-loop three-level boost converter (3LBC). Both converters are designed in a single prototype chip, fabricated in a 180-nm process. The PMIC's self-start operation is verified at a minimum voltage of 50mV. The functionality of both converters are verified to match with simulation results, achieving above 50% efficiency for a wide range of loads. The peak efficiencies of 65% and 83% are achieved for the 2-stage boost converter and the three level boost converter at 150mV and 180mV input voltages, respectively.