The invention provides a power conversion device, including: a voltage conversion stage, including a primary side for receiving a rectified voltage and a secondary side for generating a rectified voltage according to the rectified voltage, wherein the primary side includes a primary side switch; a switch control circuit having a startup status and a normal operation status, the switch control circuit being configured to operably provide a control signal to a control terminal of the primary side switch; a startup circuit, providing a current to the control terminal when the switch control circuit is in the startup status, to at least partially conduct the primary side switch; and a slow soft-startup circuit, wherein when the switch control circuit is in the startup status and the output voltage does not reach a predetermined voltage in a first predetermined time period, the slow soft-startup circuit reduces a total current quantity supplied to the control terminal in a second predetermined time period which is after the first predetermined time period.

A power supply device includes a rectifying unit for rectifying an AC input voltage, a voltage conversion unit including a switching element and configured to receive a rectified input voltage from the rectifying unit and obtain an output voltage voltage-converted by a switching operation of the switching element, and a voltage comparison unit configured to generate a comparison signal between the output voltage and a set output voltage. The power supply device further includes an oscillation unit configured to output a control signal having an oscillation period and an oscillation-stop period as a control signal for controlling an ON/OFF of the switching element. The oscillation period and the oscillation-stop period of the control signal are controlled by the comparison signal outputted from the voltage comparison unit, and a pulse duty ratio of the control signal in the oscillation period is variably controlled based on the input voltage.

A LED driving system has an energy storage component receiving an input voltage, a power switch coupled between the energy storage component and a reference ground, a first output switch coupled between the energy storage component and a first output terminal, a second output switch coupled between the energy storage component and a second output terminal, and a control circuit, wherein the first output terminal produces a first output voltage to supply power for a first LED array, the second output terminal produces a second output voltage to supply power for a second LED array, the control circuit controls a duty cycle of the first output switch according to voltages at cathode terminals of multiple LED strings in the LED array and controls a duty cycle of the second output switch according to voltages at cathode terminals of multiple LED strings in the second LED array.

A LED driving system has an energy storage component receiving an input voltage, a power switch coupled between the energy storage component and a reference ground, a first output switch coupled between the energy storage component and a first output terminal, a second output switch coupled between the energy storage component and a second output terminal, and a control circuit, wherein the first output terminal produces a first output voltage to supply power for a first LED array, the second output terminal produces a second output voltage to supply power for a second LED array, the control circuit controls a duty cycle of the first output switch according to voltages at cathode terminals of multiple LED strings in the LED array and controls a duty cycle of the second output switch according to voltages at cathode terminals of multiple LED strings in the second LED array.

The present disclosure relates to a power grid separating apparatus using a latch relay and a method thereof. An exemplary embodiment of the present disclosure provides a power net separating apparatus including: a switch configured to have a first end connected to a first power source and a second end connected to a second power source; a latch relay coil configured to control on and off of the switch; a first signal terminal connected to the first power source; a second signal terminal to which a connection signal for opening the switch is applied; a third signal terminal configured to serve as a power terminal of the latch relay coil; a fourth signal terminal to which a blocking signal for closing the switch is applied; and a fifth signal terminal connected to the second power source.

A power converter includes a first load terminal used to supply a current to a load and a second load terminal used to return a feedback voltage based on the current. A calibration circuit supplies a calibrated voltage processed from the feedback voltage, and a hysteretic comparator controls a current level of the current based on a difference between the feedback voltage and the calibrated voltage.

A power converter includes a first load terminal used to supply a current to a load and a second load terminal used to return a feedback voltage based on the current. A calibration circuit supplies a calibrated voltage processed from the feedback voltage, and a hysteretic comparator controls a current level of the current based on a difference between the feedback voltage and the calibrated voltage.

A semiconductor apparatus includes: a switch circuit connected between a first power supply terminal and an output terminal; a switching element connected between the output terminal and a second power supply terminal; and a control circuit that, when a predetermined period has elapsed since the entry of the switch circuit into an ON state in response to an enable signal, causes the switching element to start a switching operation to increase a power supply voltage supplied between the first power supply terminal and the second power supply terminal.

The present invention discloses a voltage reference buffer circuit. An embodiment of the voltage reference buffer circuit includes: a first bias generator configured to generate a first bias voltage; a second bias generator configured to generate a second bias voltage different from the first bias voltage; a first driving component coupled to a high voltage terminal, the first bias generator and a reference voltage output terminal, and configured to control a reference voltage at the reference voltage output terminal according to the first bias voltage; and a second driving component coupled to the reference voltage output terminal, the second bias generator and a low voltage terminal, and configured to control a current between the reference voltage output terminal and the second driving component according to the second bias voltage.

The present invention discloses a voltage reference buffer circuit. An embodiment of the voltage reference buffer circuit includes: a first bias generator configured to generate a first bias voltage; a second bias generator configured to generate a second bias voltage different from the first bias voltage; a first driving component coupled to a high voltage terminal, the first bias generator and a reference voltage output terminal, and configured to control a reference voltage at the reference voltage output terminal according to the first bias voltage; and a second driving component coupled to the reference voltage output terminal, the second bias generator and a low voltage terminal, and configured to control a current between the reference voltage output terminal and the second driving component according to the second bias voltage.