Abstract: Bridgeless boost PFC circuits and systems providing an improved method of current sensing using two current sensing resistors is envisaged. Analog switches are provided to select one of the two current sensing resistors based on the polarity of the AC line. An amplifier is provided to eliminate use of resistors with large values, thus resulting in lower power loss and efficient systems.

Abstract: According to one example embodiment, a bridgeless boost power factor correction (PFC) system includes a first input for connection to a first line of an alternating current (AC) source and a second input for connection to a second line of the AC source. The PFC system includes an output for delivering an output of the bridgeless boost PFC system, a first boost choke coupled to the first input and a second boost choke coupled to the second input. A common mode choke is coupled between the first and second input and the first and second boost choke. A first X capacitor is coupled between the first input and the output and a second X capacitor coupled between the second input and the output.

Abstract: Bridgeless boost PFC circuits and systems providing an improved method of current sensing using two current sensing resistors is envisaged. Analog switches are provided to select one of the two current sensing resistors based on the polarity of the AC line. An amplifier is provided to eliminate use of resistors with large values, thus resulting in lower power loss and efficient systems.

Abstract: According to one example embodiment, a bridgeless boost power factor correction (PFC) system includes a first input for connection to a first line of an alternating current (AC) source and a second input for connection to a second line of the AC source. The PFC system includes an output for delivering an output of the bridgeless boost PFC system, a first boost choke coupled to the first input and a second boost choke coupled to the second input. A common mode choke is coupled between the first and second input and the first and second boost choke. A first X capacitor is coupled between the first input and the output and a second X capacitor coupled between the second input and the output.

Abstract: In a redundant power supply system, N+1 power supply modules are operated in parallel to provide power to a single load which may be connected via a DC bus and may employ a remote voltage sensing circuit. Each power supply module includes an ORing element that isolates a corresponding AC power supply from delivering power to the load in various conditions representing a fault occurring in the system. Each ORing element and power supply module is coupled to a control circuit that drives the operations of the ORing element. The control circuit includes three comparators and associated circuitry each for detecting one of the following conditions of system failure representing by: the presence of reverse current flowing across the ORing element caused by short circuit in the system, a selective overvoltage condition caused by a power supply delivering too much voltage to the load; and a failure in an AC power supply giving rise to an undervoltage condition.