An efficiency-enhanced auto-reconfigurable 2x/3x SC charge pump for transcutaneous power transmission

An auto-reconfigurable 2x/3x switched-capacitor charge pump (SC-CP) for transcutaneous power transmission is presented in this paper. The proposed SC-CP can automatically configure its own voltage conversion ratio by adaptive control circuitry for maintaining high efficiencies of the DC/DC regulator under coupling variations. An adaptive deadtime control is developed to improve the efficiency of the proposed SCCP by minimizing the shoot-through current. Implemented in a standard 0.35-mum n-well CMOS process, the proposed SC-CP achieves peak power efficiencies of 95% (2x) and 92% (3x). The efficiency of the DC/DC regulator with the proposed SC-CP is improved by >25%, compared to that using the conventional 3x SC-CP, when the input voltage varies from 1.6 V to 2.4 V.