US 12,463,532 B2
Multi-stage DC-DC converter
Casey Hardy, South Lake Tahoe, CA (US); and Hanh-Phuc Le, San Diego, CA (US)
Assigned to The Regents of the University of California, Oakland, CA (US)
Filed by The Regents of the University of California, Oakland, CA (US)
Filed on Apr. 25, 2023, as Appl. No. 18/306,684.
Claims priority of provisional application 63/337,273, filed on May 2, 2022.
Prior Publication US 2023/0353054 A1, Nov. 2, 2023
Int. Cl. H02M 3/07 (2006.01); H02M 1/00 (2007.01)
CPC H02M 3/07 (2013.01) [H02M 1/0025 (2021.05); H02M 1/007 (2021.05); H02M 1/0095 (2021.05)] 16 Claims
OG exemplary drawing
 
1. A multi-stage DC-DC power converter, comprising:
a first switched-capacitor stage driven by an input voltage;
a second switched-capacitor stage coupled to the first switched-capacitor by an inductor coupling current source, and
a controller to control charging and discharging of a flying capacitor by the inductor coupling current source in each of the first and second switched-capacitor stages, wherein the controller operates such that:
each of the flying capacitors of the first and second switched-capacitor stages is soft charged by the inductor coupling current source and a frequency of a switched voltage across the inductor coupling current source is maintained to be high enough to limit inductor current ripple to be negligible compared to its DC component and ensure average inductor current is effectively reduced by factor equal to a voltage conversion ratio of the second switched-capacitor stage.