An Automotive-Use Battery-to-Load GaN-Based Switching Power Converter With Anti-Aliasing MR-SSM and In-Cycle Adaptive ZVS Techniques Dong Y an

Abstract

In modern automotive electronics, there are upris- ing demands on enhanced power density and reliability for power delivery systems. To achieve high power density, single- stage gallium–nitride (GaN)-based power converters at high switching frequencies ( f SW ) are highly desirable but face formi- dable reliability challenges in the aspects of electromagnetic interference (EMI) suppression and consequential output voltage V O regulation. To address these challenges, this article presents a GaN-based switching power converter that employs an anti- aliasing multi-rate spread-spectrum modulation (MR-SSM) tech- nique for EMI suppression and an in-cycle adaptive zero-voltage switching (ZVS) technique to minimize switching power losses. Compared with classic fixed-rate SSM (FR-SSM), the proposed MR-SSM technique spreads EMI spectra in a wider frequency range without aliasing spikes and, thus, reduces peak EMI more effectively. To improve efficiency, an elastic dead-time ( t dead) control facilitates in-cycle ZVS despite of a continuously changing fSW.A nI Cp r o t o t y p eb a s e do nt h i sd e s i g nw a sf a b r i c a t e do na 180-nm HV BCD process, with an active die area of 0.87 mm 2. The converter can handle a variable automotive-use battery voltage from 5 to 24 V and delivers up to 1.2-W power to a regulated output V O at 1 V , with a peak efficiency of 90.2%. It accomplishes a 29% further peak EMI reduction compared with the FR-SSM counterpart.