Abstract: A control scheme for a synchronous rectifier converter that avoids disabling the synchronous rectifiers entirely. Rather than disable the synchronous rectifier altogether to stop the flow of reverse current in light-load, startup, or shutdown conditions, the duty cycle of the synchronous rectifier is modified such that forward current is always allowed to flow through the synchronous rectifier, but the synchronous rectifier is turned off before the reverse current flow reaches a pre-determined level. This is accomplished by operating the converter in a partially synchronous mode of operation during light-load, startup, or shutdown conditions. Whether the circuit is in a light-load, startup, or shutdown condition is determined by a circuit characteristic of the converter that is sensed by the controller, such as average output current. The desired changeover point from fully-synchronous mode to the partially synchronous mode is set to a predetermined level of output current for the converter.

Abstract: Compared with the prior art, the invention offers several extra benefits in addition to providing a dc current signal from a sensed peak current signal. First, the control switch is referenced to the ground, and therefore floating drive for the series switch in the prior art is not necessary. Second, the peak current signal is always available regardless of the status of the control switch. By separating the peak and average current signals, the converter can be better controlled and both peak current mode control and current sharing control can be optimized. Finally, referencing the peak current and average current signals to the different grounds provides freedom to implement different control schemes.

Abstract: A control scheme for a synchronous rectifier converter that avoids disabling the synchronous rectifiers entirely. Rather than disable the synchronous rectifier altogether to stop the flow of reverse current in light-load, startup, or shutdown conditions, the duty cycle of the synchronous rectifier is modified such that forward current is always allowed to flow through the synchronous rectifier, but the synchronous rectifier is turned off before the reverse current flow reaches a pre-determined level. This is accomplished by operating the converter in a partially synchronous mode of operation during light-load, startup, or shutdown conditions. Whether the circuit is in a light-load, startup, or shutdown condition is determined by a circuit characteristic of the converter that is sensed by the controller, such as average output current. The desired changeover point from fully-synchronous mode to the partially synchronous mode is set to a predetermined level of output current for the converter.

Abstract: For use with a power converter having a modulator, a controller and a method of operating the same. In one embodiment, the controller includes: (1) signal processing circuitry that develops a unified control signal based on an output voltage, an output current and a current sharing signal of the power converter and (2) compensation circuitry, coupled to the signal processing circuitry, that compares the unified control signal with a reference signal to develop a modulator control signal for the modulator.

Abstract: An interface circuit for, and method of, allowing first and second power converter systems to function in parallel and a power supply incorporating the controller or the method. In one embodiment, the interface circuit includes: (1) a set point selection circuit, coupled to first and second converter controllers of the first and second power converter systems, respectively, that selects one of the first and second power converter systems to provide a global set point voltage signal and (2) a bus, coupled to the set point selection circuit, that conveys the global set point voltage signal to the first and second power converter systems, the set point selection circuit isolating a nonselected one of the first and second converter controllers from the bus.

Abstract: A boost converter module, a method of manufacturing the module and a power converter employing one or more of the same. In one embodiment, the boost converter module includes: (1) a power switch, (2) first and second snubber diodes series-coupled between the power switch and a converter output, (3) a snubber capacitor and a boost diode series-coupled across the second snubber diode and (4) an encapsulant substantially surrounding the power switch, the first and second snubber diodes, the snubber capacitor and the boost diode to join the power switch, the first and second snubber diodes, the snubber capacitor and the boost diode into an integrated package, the integrated package having: (4a) a control input coupled to the power switch, (4b) a power input coupled to the power switch, (4c) a snubber inductor input, coupled to a node between the snubber capacitor and the boost diode and (4d) a power output coupled to the converter output.