A High-Efficiency Switched-Capacitance HTFET Charge Pump for Low-Input-Voltage Applications

This paper presents a high-efficiency switched-capacitance charge pump in 20 nm III-V heterojunction tunnel field-effect transistor (HTFET) technology for low-input-voltage applications. The steep-slope and low-threshold HTFET device characteristics are utilized to extend the input voltage range to below 0.20 V. Meanwhile, the uni-directional current conduction is utilized to reduce the reverse energy loss and to simplify the non-overlapping phase controlling. Furthermore, with unidirectional current conduction, an improved cross-coupled charge pump topology is proposed for higher voltage output and PCE. Simulation results show that the proposed HTFET charge pump with a 1.0 kΩ resistive load achieves 90.4% and 91.4% power conversion efficiency, and 0.37 V and 0.57 V DC output voltage, when the input voltage is 0.20 V and 0.30 V, respectively.