Zero Reversion Loss, High-Efficiency Charge Pump for Wide Output Current Load Range

Switched-capacitor charge pumps provide fully-integrated voltage conversion in integrated circuits, without the need for large area inductors. Traditional cross-coupled charge pump topologies are limited by reversion loss, where charge flows backward during a pumping cycle due to non-ideal switch control clocks. In this work, we present two modified charge pump topologies that eliminate reversion loss while adding minimal control complexity. A detailed comparison with recent published approaches is presented. The single-stage charge pump Designs I and II are implemented in a standard 180 nm CMOS process and exhibit peak efficiency of 81.9% and 83.2%, respectively, and more than 70% power efficiency is achieved across a load current range from 100-900 μA for Design II. The presented approach improves efficiency while decreasing required stage capacitance several-fold, achieving over 87 mW/mm
²
power density.