Abstract: A continuous load high-power flyback converter includes a first transformer having a first primary winding, a first secondary winding, and a first auxiliary winding, and a second transformer having a second primary winding, a second secondary winding, and a second auxiliary winding. The first primary winding and the second primary winding are connected in parallel between a power source and a transistor. The first secondary winding and the second secondary winding are connected in series to a diode and form an output of the continuous load high-power flyback converter. A load is connected between the output and ground. The first auxiliary winding and the second auxiliary winding are connected in series, and used to generate a control signal for the transistor. Connecting the primary windings in parallel and the secondary windings in series reduces the reflected voltage on the transistor for a given output voltage.

Abstract: A PFC flyback converter topology is disclosed. The topology can be implemented in a single-stage and is particularly useful in driving dimmable solid state light sources in lighting applications, though other applications susceptible to instability at very low loading conditions may also benefit. Stable operation is achieved over a broader range of loading using the converter topology as provided herein. In a dimmable lighting application, stable operation (e.g., flicker-free lighting) is achieved at very low dimming levels (e.g., where the load is less than 10% full load). In some topologies, a serial arrangement including a stabilization network and a switch is connected across the solid state light sources or other load. A microcontroller unit controls the duty cycle of the switch to selectively steer excess current from the solid state light sources to the stabilization circuit, at very low dimming conditions.

Abstract: Techniques are disclosed for providing a stable output voltage in switching mode power supplies (SMPS). An SMPS includes a switching converter for powering a load, a passive startup circuit for initially providing an internal voltage supply for powering switching electronics when the mains is turned on, and a feedback circuit providing the internal voltage supply once the switching converter starts switching. The SMPS also includes a decoupling circuit that decouples or otherwise isolates the gain of the passive startup circuit from the feedback circuit, so as to prevent false dynamic overvoltage protection triggers. The decoupling circuit is implemented, for instance, with the addition of two or three passive components, such as a diode and a capacitor, or a diode, a capacitor, and a resistor. Preventing false triggering of the dynamic overvoltage protection in turn provides a more stable output voltage from the SMPS.