A Dual-Input Bidirectional Three-Level Battery Charger Using Coarse-Fine VCF Balancing and Frequency Foldback Control for Foldable

Abstract

Foldable mobile applications recently have been leading the battery charger to have a slim height with a small form-factor and high e fficiency at higher input voltages to increase the power density. Another trend for mobile applications is the power sharing, which enables to supply two mobile devices simultaneously. To meet these requirements, this article presents a dual-input bidirectional three-level battery charger. With the dual-input bidirectional structure, it can support the battery charg