An Asynchronous 1.8MHz DC/DC Boost Converter Implemented in the Current Domain for Cellular Phone Lighting Management

This paper presents an asynchronous 1.8MHz DC/DC boost converter used to generate any output voltage between 5.6V and 25V out of a single cell Li-ion battery. The output is controlled by a pulse-width-modulated (PWM) current programmed mode (CPM) controller. An area-efficient controller with excellent dynamic performance is achieved by using an adaptive P compensator; the proposed control circuit is entirely implemented in the current domain. The typical conversion efficiency of 80% at 120mA is mainly determined by conduction and switching losses in the external components. A 0.25mum standard CMOS technology with thick metal stack and a 5V device allows a direct-to-battery connection; the area is 0.34mm²