Sahana Krishnan

EECS Department, University of California, Berkeley

Technical Report No. UCB/EECS-2024-79

May 10, 2024

http://www2.eecs.berkeley.edu/Pubs/TechRpts/2024/EECS-2024-79.pdf

With the move to a 48 V distribution rail in data center power delivery architectures and automotive powertrains, high performance hybrid switched-capacitor (SC) converters have become an attractive power delivery solution in both spaces. However, automotive power systems present unique design challenges due to strict electromagnetic interference (EMI) and reliability requirements. This thesis investigates a regulating Dickson-based hybrid SC topology with low inherent EMI, and discusses the incorporation of control-based EMI mitigation techniques such as resonant and above resonant operation, as well as spread spectrum frequency modulation (SSFM). The impact of such techniques on efficiency in hybrid SC converters is explored, as well as utilizing layout techniques and passive filter designs to achieve EMI compliance. A hardware prototype combining a power stage and passive input filter is built to demonstrate the merit of hybrid SC topologies for use in 48 V automotive systems. The proposed filter and modulation schemes enable this converter to meet the CISPR 25, automotive EMI standard. A 150 W hardware prototype is built and tested to demonstrate the merit of hybrid SC topologies for use in 48 V automotive systems. The converter achieves a peak efficiency of 97.1% for 48 V-to-5 V regulated operation at 150 W of output power and meets CISPR 25, Class 5 EMI regulation limits.

Advisors: Robert Pilawa-Podgurski

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BibTeX citation:

@mastersthesis{Krishnan:EECS-2024-79,
    Author= {Krishnan, Sahana},
    Title= {An EMI-Compliant and Automotive-Rated 48 V to Point-of-Load Dickson-Based Hybrid Switched-Capacitor DC-DC Converter},
    School= {EECS Department, University of California, Berkeley},
    Year= {2024},
    Month= {May},
    Url= {http://www2.eecs.berkeley.edu/Pubs/TechRpts/2024/EECS-2024-79.html},
    Number= {UCB/EECS-2024-79},
    Abstract= {With the move to a 48 V distribution rail in data center power delivery architectures and automotive powertrains, high performance hybrid switched-capacitor (SC) converters have
become an attractive power delivery solution in both spaces. However, automotive power systems present unique design challenges due to strict electromagnetic interference (EMI)
and reliability requirements. This thesis investigates a regulating Dickson-based hybrid SC topology with low inherent EMI, and discusses the incorporation of control-based EMI
mitigation techniques such as resonant and above resonant operation, as well as spread spectrum frequency modulation (SSFM). The impact of such techniques on efficiency in
hybrid SC converters is explored, as well as utilizing layout techniques and passive filter designs to achieve EMI compliance. A hardware prototype combining a power stage and
passive input filter is built to demonstrate the merit of hybrid SC topologies for use in 48 V automotive systems. The proposed filter and modulation schemes enable this converter to meet the CISPR 25, automotive EMI standard. A 150 W hardware prototype is built and tested to demonstrate the merit of hybrid SC topologies for use in 48 V automotive systems. The converter achieves a peak efficiency of 97.1% for 48 V-to-5 V regulated operation at 150 W of output power and meets CISPR 25, Class 5 EMI regulation limits.},
}

EndNote citation:

%0 Thesis
%A Krishnan, Sahana 
%T An EMI-Compliant and Automotive-Rated 48 V to Point-of-Load Dickson-Based Hybrid Switched-Capacitor DC-DC Converter
%I EECS Department, University of California, Berkeley
%D 2024
%8 May 10
%@ UCB/EECS-2024-79
%U http://www2.eecs.berkeley.edu/Pubs/TechRpts/2024/EECS-2024-79.html
%F Krishnan:EECS-2024-79