LLC Resonance

LLC usually refers to a resonant DC/DC converter topology (series resonant inductor, magnetizing inductance, and resonant capacitor) used inside power supplies. Wireless power also uses resonant L–C networks — but the “transformer” is a loosely coupled coil pair across an air gap, not a tightly coupled isolation transformer on a PCB.

01Useful overlap

• Both rely on resonant tanks and often soft switching.
• Gain curves vs frequency are central design artifacts in both domains.
• Frequency modulation and phase-shift control ideas transfer conceptually.

02Important difference

In a classic LLC PSU, k is high and leakage is a designed resonant inductor. In WPT, k varies with parking position and the mutual inductance is the power channel. Treating a dock as “just an LLC brick” without modeling misalignment will under-estimate voltage stress and miss frequency splitting. Use LLC intuition for soft switching — then complete a proper WPT coupling model.