Flyback / Resonant Topology

Circuit architectures used in PEMF drivers. A flyback driver stores energy in the coil's magnetic field during the on-phase and releases it rapidly during turn-off. This produces fast field collapse (high fall-edge slew rate). A resonant topology uses an LC tank circuit tuned to the operating frequency. The coil and a capacitor exchange energy sinusoidally, producing smooth waveforms with rise times set by the resonant frequency rather than L/R alone. Resonant designs are efficient but less flexible for frequency tuning.