A Single-Inductor Dual-Ouput (SIDO) DC-DC Converter for Implantable Medical Devices in 180nm Standard CMOS Process

Abstract

In this paper, a single-inductor dual-output (SIDO) buck converter is developed for implantable medical devices. The stacked power stage with startup circuit is designed to avoid over-stress issue in 180nm CMOS process for 3.4 V to 5 V battery input. The converter provides two regulated outputs for the charge pump (V-OUT1 = 3 V) and the digital circuits (V-OUT2 = 2 V) with low cross regulation with pulse-skip modulation. An adaptive on-time (AOT) circuit adjusts on time dynamically based on the input voltage (V-IN) to obtain high conversion efficiency and low output voltage ripple under different V-IN. The measurement results demonstrates that the proposed converter achieves peak efficiency of 93.6% with an available input voltage of 3.4 V to 5 V.