Abstract: A power converter includes a controller having at least one input for monitoring a rate of change of an operating parameter of the power converter. The controller is configured for comparing the monitored rate of change of the operating parameter with an allowable rate of change for the operating parameter, and for generating a fault signal when the monitored rate of change of the operating parameter deviates from the allowable rate of change for the operating parameter. The operating parameter for which the rate of change is monitored may be, for example, a temperature, a current and/or a voltage in the power converter.

Abstract: A power converter includes a controller and at least one output terminal for providing an output voltage and an output current to a load. The controller is configured for monitoring the output voltage and the output current and calculating an efficiency of the power converter based on the monitored output voltage and output current. The controller is also configured to generate a fault signal after detecting a degradation in the power converter efficiency.

Abstract: A method for detecting a performance degradation of a fan in a power converter is disclosed. The method includes monitoring a speed of the fan and detecting the performance degradation of the fan based, at least in part, on the monitored speed. The method further includes generating a warning signal after detecting the performance degradation of the fan. According to another aspect, a power converter includes a fan and a processor operably coupled to the fan for monitoring a speed of the fan. The processor is configured for detecting a performance degradation of the fan based, at least in part, on the monitored fan speed. The processor generates a warning signal after detecting the performance degradation of the fan.

Abstract: A power converter includes a controller and at least one output terminal for providing an output voltage and an output current to a load. The controller is configured for monitoring the output voltage and the output current and calculating an efficiency of the power converter based on the monitored output voltage and output current. The controller is also configured to generate a fault signal after detecting a degradation in the power converter efficiency.

Abstract: A power converter includes a controller and at least one circuit component. The controller is configured for monitoring stress on the circuit component during operation of the power converter and estimating a remaining life of the circuit component based on the monitored stress.

Abstract: A power converter includes a controller having at least one input for monitoring a rate of change of an operating parameter of the power converter. The controller is configured for comparing the monitored rate of change of the operating parameter with an allowable rate of change for the operating parameter, and for generating a fault signal when the monitored rate of change of the operating parameter deviates from the allowable rate of change for the operating parameter. The operating parameter for which the rate of change is monitored may be, for example, a temperature, a current and/or a voltage in the power converter.

Abstract: A circuit for controlling the operation of synchronous rectifiers. The circuit delays the turn-off of the synchronous rectifiers in accordance with the load current. The magnitude of the load current is examined to determine which of a plurality of delay elements is selected to delay turn-off of the synchronous rectifiers. Delay is accomplished by holding up for a predetermined time period one of a plurality of control signals utilized to determine when the synchronous rectifier should be turned-off.

Abstract: A circuit for controlling the operation of synchronous rectifiers. The circuit delays the turn-off of the synchronous rectifiers in accordance with the load current. The magnitude of the load current is examined to determine which of a plurality of delay elements is selected to delay turn-off of the synchronous rectifiers. Delay is accomplished by holding up for a predetermined time period one of a plurality of control signals utilized to determine when the synchronous rectifier should be turned-off.

Abstract: A soft switched zero voltage transition full bridge converter for reducing power loss at very light loads for zero voltage switching (ZVS) converters operating at high frequency. The converter has four switches in two switching legs each of two switches connected in series between two input voltage terminals, junction points of the legs being coupled to a primary winding of a transformer, a secondary winding from which an output voltage of the converter is derived by rectifying and filtering. A pair of capacitive voltage dividers are connected between the input terminals, each formed by two small capacitors each having a parallel-connected diode. The output voltage is regulated by phase shift control of the switches. The capacitors are selected small enough for storing only enough energy to enable ZVS in conjunction with two resonant inductors. The converter enables reduced component size of the inductors and energy storage capacitors.

Abstract: A circuit for reducing the internal power losses of a soft switching full bridge converter at light loads and enables very high frequency operation without using a cold plate approach. In a preferred embodiment, the circuit includes a resonant inductor and blocking inductor on the primary side of the converter arranged so as to provide the reduced losses for zero voltage switching bridge converter. The circuit provides the above benefits even for converters having a power transformer with very low leakage inductance. The circuit is not dependent on the presence of a high leakage inductance for the power transformer. The circuit can be used in soft switched half bridge or full bridge converters. The inventive circuit can also be used in a hard switching full bridge or half bridge converter for achieving zero voltage switching at reduced cost with reduced losses at light load, if the operating duty cycle of the converter is set near fifty percent.