A 19.8W/29.6W Hybrid Step-Up/Down DC-DC Converter with 97.2% Peak Efficiency for 1-Cell/2-Cell Battery Charger Applications

초록

This paper presents an inductor-first hybrid step-up/down DC-DC converter for one-and two-cell battery chargers. The proposed architecture can improve efficiency by lowering inductor current as well as less charge sharing loss of the flying capacitor. The battery can be isolated from the input without using extra reverse blocking device which is necessary for the charger application. The design also can replace the discrete inductor with the USB cable inductance and avoid heat loss from the mobile device. The proposed converter has been implemented in a 180nm BCDMOS process. The peak efficiency is 96.9% at 5V input for one-cell, and 97.2% at 9V input for two-cell battery. The measured maximum output power is 19.8W and 29.6W for one-cell and two-cell battery applications, respectively. The onboard peak efficiency is 96% employing the USB cable. © 2023 JSAP.