Protection of EMC filter components due to failure of boost stage/circuit to prevent smoke, sound or fire in a boost stage under fault condition

摘要

A circuit device and method for protecting EMC components from fault conditions that may negatively affect the components, such as high power dissipation in EMC components when/if the boost stage stops working or malfunctions and preventing smoke and fire in case the boost stage switching device fails, shorts, or is defective. The device is designed so that the chopper stage (following the boost stage) is latched off if/whenever the boost stage stops working. According to the methods of the invention, whenever such a fault occurs at the boost stage, the circuit immediately disables the stage that provides power to the output load (i.e., load-power-supply stage). This disabling of the load-power-supply stage then prevents very high currents from flowing through the EMC components and thus protects the EMC components from overheating and/or causing a fire or smoke.