Patent ID: 7330343

Claim:
A current-limiting protection circuit for a power supply, which applies to a power supply that comprises at least: a power-transformation circuit, which outputs direct-current power to drive at least one load; and a current-limiting protection circuit, which is electrically coupled to said power-transformation circuit and determines the power-usage status of said load, wherein said current-limiting protection circuit comprises: a power-detection circuit, electrically coupled to said power-transformation circuit and said load, and acquiring a usage-power value from the direct-current power of said load, wherein said usage-power value is compared with a preset power-limiting value in order to output a protection signal; a time-delay alarm circuit, electrically coupled to said power-detection circuit and receiving said protection signal, wherein said time-delay alarm circuit further comprises: a time-delay trigger unit and an alarm unit, and wherein once said time-delay trigger unit receives said protection signal said alarm unit outputs an alarm signal to indicate heavy-load state and a full-load state of said load, and said time-delay trigger unit begins to set a delay time, and once said delay time expires, a triggering signal will be sent to said current-limiting protection circuit to shut or pause the direct-current power output of said power-transformation circuit; a disabling switch connected between said time-delay trigger unit and said current-limiting protection circuit, said disabling switch being selectively opened to prevent said triggering signal from reaching said current-limiting protection circuit; a reference-power circuit, electrically coupled to said power-detection circuit, and providing said power-limiting value for said power-detection circuit.