When the switch is turned off, the first capacitor may discharge. Further, the second diode and the second capacitor are used to transfer energy from a leakage inductance between the primary winding and the second winding to a capacitor, clamping a voltage spike. The clamping winding is employed to allow for a direct current (DC) offset compared to the primary winding. The first inductor discharges the capacitor, but allowing energy to be returned to the power source instead of being dissipated.

Therefore, at the moment that the switch is turned off, the first capacitor conducting through the first diode will slow the primary winding transition, reducing Electromagnetic interference (EMI). The first capacitor and the first diode do little to limit the voltage spike.

In conclusion, the energy used to charge the first capacitor was derived from the second capacitor that stored energy from the previous cycle inductive spike, returning the clamped energy to the power source. Therefore, the energy in the first capacitor and the energy in the second capacitor may not be consumed by a resistor, and power consumption of the low loss snubber may be decreased.

Other objectives, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.