Abstract: The present application is a converter having a low loss snubber. The low loss snubber of the converter includes a clamping winding, a first capacitor, and a second capacitor. The clamping winding is magnetically coupled with a primary winding of a transformer of the converter. The primary winding to a secondary winding of the transformer leakage inductance energy is recovered by storing the energy in the second capacitor. When the second capacitor is discharging, the energy in the second capacitor may be further transferred to the first capacitor. When the first capacitor is discharging, energy in the first capacitor may be further returned 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.

Abstract: Systems and methods are disclosed for providing a current boost to support a voltage. In an embodiment, an apparatus comprises a voltage node; a switch coupled to the voltage node; a sensing circuit including an input coupled to the voltage node and an output for providing a corresponding voltage; and a voltage regulator coupled to receive the corresponding voltage and coupled to control the switch responsive to the received corresponding voltage. In an embodiment, a method comprises sensing a voltage; using a voltage regulator to turn on a switch responsive to the sensed voltage being less than a certain value; and providing additional current through the on switch to substantially maintain the voltage from being less than the certain value.

Abstract: An off-line switching power supply is described which controls the switching transistor of a fly-back circuit in such a fashion as to achieve better than 0.99 power factor control. The technique used for power factor control allows the switching power supply to operate either from AC or DC sources. The power supply operating from an AC source will accept all international voltages and line frequencies as input to produce a well-regulated DC output. The inductor of the fly-back circuit is maintained at the verge of continuous/discontinuous operation by the power factor control circuit to achieve a high efficiency operation and to minimize switching losses. The power factor correction circuit uses pulsewidth modulation and frequency modulation to control the switching transistor and maintain a high power factor under varying line and load conditions. The power supply also includes integral current limiting protection and RFI filtering for safe and quiet operation.