Abstract: Disclosed is an SMPS for preventing abnormal overcurrents. A circuit having a short circuit delay is used to generate a control signal for turning off a main switch (i.e., a switching MOS transistor) when the overcurrent occurs, that is, in an initial startup or when a protection circuit is operated. Accordingly, a drain-source voltage of the main switch is reduced when the main switch is turned off, and a switching MOS transistor with a low withstanding voltage can be used.

Abstract: In one embodiment, a switching mode power supply (SMPS) include: a power supply for supplying power to a secondary coil of a transformer according to an operation of a main switch, the main switch being coupled to a primary coil of the transformer; a feedback circuit for generating a feedback voltage corresponding to an output voltage; a control module for stopping the main switch when the feedback voltage is lower than a reference voltage in a standby operation mode; an integrated circuit (IC) power unit for generating a constant voltage, the IC power supply being coupled to the secondary coil of the transformer; and a current generator for using the constant voltage to generate a plurality of constant currents for operating a plurality of ICs, and generating a constant current from among the constant currents when the main switch performs no switching on/off operation.

Abstract: Disclosed is an SMPS for preventing abnormal overcurrents. A circuit having a short circuit delay is used to generate a control signal for turning off a main switch (i.e., a switching MOS transistor) when the overcurrent occurs, that is, in an initial startup or when a protection circuit is operated. Accordingly, a drain-source voltage of the main switch is reduced when the main switch is turned off, and a switching MOS transistor with a low withstanding voltage can be used.

Abstract: In one embodiment, a switching mode power supply (SMPS) may comprise: a power supply for supplying power to a secondary coil of a transformer according to an operation of a main switch, the main switch being coupled to a primary coil of the transformer; a feedback circuit for generating a feedback voltage corresponding to an output voltage; a control module for stopping the main switch when the feedback voltage is lower than a reference voltage in a standby operation mode; an integrated circuit (IC) power unit for generating a constant voltage, the IC power supply being coupled to the secondary coil of the transformer; and a current generator for using the constant voltage to generate a plurality of constant currents for operating a plurality of ICs, and generating a constant current from among the constant currents when the main switch performs no switching on/off operation.