Innovative Packaging Strategy for MLCCs for High Current AC Applications Aimed at Reducing Parasitic Inductance

Resonant converters facilitate high-frequency switching applications due to their ability to utilize zero voltage switching, which significantly reduces switching losses. However, their performance and capacity to achieve higher switching frequencies are contingent upon the efficiency of the resonant tank, making it crucial to reduce losses in resonant capacitors and inductors. This work uses Multilayered Ceramic Capacitors (MLCC) for their high self-resonant frequency (SRF) and presents a packaging design that lowers the Equivalent Series Inductance (ESL) of MLCCs and optimizes their trace path inductance. This approach enhances SRF, improves electromagnetic interference (EMI) resilience, and broadens the switching frequency range. Furthermore, the electro-thermal performance of the MLCCs with their modified layout has been evaluated in a 13.6 kW LLC DC-DC converter operating at 200 kHz switching frequency, with a DC bus of 400V and a resonant tank current of 34 A<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">rms</inf>.