Abstract: A detector compares a drain voltage with a first threshold voltage and outputs a first detection signal. An ON-counter detects a period of time during which current flows in a switching circuit based on the first detection signal, counts the period of time based on a predetermined clock cycle, and outputs an ON-count value. A first comparator receives the ON-count value and an ON-threshold value and outputs a first comparison signal when the ON-count value and the ON-threshold value match. A second comparator receives the ON-count value and a decreased ON threshold value, compares the ON-count value and the decreased ON-threshold value, and outputs a second comparison signal. An ON-mask time adjuster receives the second comparison signal and outputs an ON-threshold value for adjusting a mask time and a decreased ON-threshold value that is less than the ON threshold value.

Abstract: An excitation current detection circuit is disclosed. A transformer comprises a primary winding, an auxiliary winding, and a secondary winding. A first voltage detector detects a positive voltage of an auxiliary winding voltage. A second voltage detector detects a negative voltage of the auxiliary winding voltage. A first voltage controlled oscillator generates a first clock with a frequency proportional to the positive voltage during a period when the auxiliary winding voltage is the positive voltage. A second voltage controlled oscillator generates a second clock with a frequency proportional to the negative voltage during a period when the auxiliary winding voltage is the negative voltage. A counter outputs a counter value, which is added in one of cycles of the first clock and the second clock and subtracted in the other cycle of the first clock and the second clock as a detected value of an excitation current.

Abstract: A detector compares a drain voltage with a first threshold voltage and outputs a first detection signal. An ON counter detects a period of time during which a current flows in a switching, counts the period of time based on a predetermined clock cycle. An OFF counter detects a period of time during which a current flow through the body diode in a state where no current flows in the switching circuit, counts the period of time. An off-time setting circuit sets the time to turn off the switching circuit. A first comparison circuit compares the cycle count value with turn off time. A second comparison circuit compares a cycle count value output by the ON counter with a comparison result output by the first comparison circuit and outputs a signal to stop transmitting a PWM signal.

Abstract: A detector compares a drain voltage with a first threshold voltage and outputs a first detection signal. An ON-counter detects a period of time during which current flows in a switching circuit based on the first detection signal, counts the period of time based on a predetermined clock cycle, and outputs an ON-count value. A first comparator receives the ON-count value and an ON-threshold value and outputs a first comparison signal when the ON-count value and the ON-threshold value match. A second comparator receives the ON-count value and a decreased ON threshold value, compares the ON-count value and the decreased ON-threshold value, and outputs a second comparison signal. An ON-mask time adjuster receives the second comparison signal and outputs an ON-threshold value for adjusting a mask time and a decreased ON-threshold value that is less than the ON threshold value.

Abstract: A power conversion device according to one or more embodiments may include: a microcomputer; and an output circuit controlled by the microcomputer, including an output unit that converts an input power into a predetermined power and outputs the predetermined power, an internal power source that supplies a power source to the microcomputer, a driver that drives the output unit by a signal from the microcomputer, and a microcomputer stop transition unit that, when an operation of the power conversion device is stopped, outputs a microcomputer stop signal to the microcomputer and causes an operation of the microcomputer to transition to a stop state. In one or more embodiments, after the microcomputer stop transition unit causes the operation of the microcomputer to transition to a stop state, the microcomputer or the output circuit may stop an output of the internal power source.

Abstract: A device and method for controlling a power converter. The device includes an activation terminal configured to obtain a first voltage based on the input voltage; a controlling terminal configured to obtain a second voltage based on the output voltage; and a digital controller configured to obtain a driving power based on the first voltage and/or the second voltage; the digital controller is configured to obtain the driving power at least based on the first voltage when the power converter is stopped. Therefore, a sufficient driving power can be provided for the digital controller even when the power converter is stopped.

Abstract: A power conversion device according to one or more embodiments may include: a microcomputer; and an output circuit controlled by the microcomputer, including an output unit that converts an input power into a predetermined power and outputs the predetermined power, an internal power source that supplies a power source to the microcomputer, a driver that drives the output unit by a signal from the microcomputer, and a microcomputer stop transition unit that, when an operation of the power conversion device is stopped, outputs a microcomputer stop signal to the microcomputer and causes an operation of the microcomputer to transition to a stop state. In one or more embodiments, after the microcomputer stop transition unit causes the operation of the microcomputer to transition to a stop state, the microcomputer or the output circuit may stop an output of the internal power source.

Abstract: A power conversion device may include: a microcomputer; and an output circuit controlled by the microcomputer, including an output unit that converts an input power into a predetermined power and outputs the predetermined power, an internal power source that supplies a power source to the microcomputer, a driver that drives the output unit by a signal from the microcomputer, and a microcomputer stop transition unit that, when an operation of the power conversion device is stopped, outputs a microcomputer stop signal to the microcomputer and causes an operation of the microcomputer to transition to a stop state. In one or more embodiments, after the microcomputer stop transition unit causes the operation of the microcomputer to transition to a stop state, the microcomputer or the output circuit may stop an output of the internal power source.

Abstract: A device and method for controlling a power converter. The device includes an activation terminal configured to obtain a first voltage based on the input voltage; a controlling terminal configured to obtain a second voltage based on the output voltage; and a digital controller configured to obtain a driving power based on the first voltage and/or the second voltage; the digital controller is configured to obtain the driving power at least based on the first voltage when the power converter is stopped. Therefore, a sufficient driving power can be provided for the digital controller even when the power converter is stopped.

Abstract: A power conversion device according to one or more embodiments may include: a microcomputer; and an output circuit controlled by the microcomputer, including an output unit that converts an input power into a predetermined power and outputs the predetermined power, an internal power source that supplies a power source to the microcomputer, a driver that drives the output unit by a signal from the microcomputer, and a microcomputer stop transition unit that, when an operation of the power conversion device is stopped, outputs a microcomputer stop signal to the microcomputer and causes an operation of the microcomputer to transition to a stop state. In one or more embodiments, after the microcomputer stop transition unit causes the operation of the microcomputer to transition to a stop state, the microcomputer or the output circuit may stop an output of the internal power source.

Abstract: A power conversion device according to one or more embodiments may include: a microcomputer; and an output circuit controlled by the microcomputer, including an output unit that converts an input power into a predetermined power and outputs the predetermined power, an internal power source that supplies a power source to the microcomputer, a driver that drives the output unit by a signal from the microcomputer, and a microcomputer stop transition unit that, when an operation of the power conversion device is stopped, outputs a microcomputer stop signal to the microcomputer and causes an operation of the microcomputer to transition to a stop state. In one or more embodiments, after the microcomputer stop transition unit causes the operation of the microcomputer to transition to a stop state, the microcomputer or the output circuit may stop an output of the internal power source.

Abstract: A power conversion device according to one or more embodiments may include: a microcomputer; and an output circuit controlled by the microcomputer, including an output unit that converts an input power into a predetermined power and outputs the predetermined power, an internal power source that supplies a power source to the microcomputer, a driver that drives the output unit by a signal from the microcomputer, and a microcomputer stop transition unit that, when an operation of the power conversion device is stopped, outputs a microcomputer stop signal to the microcomputer and causes an operation of the microcomputer to transition to a stop state. In one or more embodiments, after the microcomputer stop transition unit causes the operation of the microcomputer to transition to a stop state, the microcomputer or the output circuit may stop an output of the internal power source.

Abstract: A switching power supply device that switches setting of an output voltage based on an external signal according to one or more embodiments includes: a transformer including a primary winding and n secondary windings; n synchronous rectification elements provided, corresponding to the n secondary windings; and n?1 switch elements that switch the secondary windings. Each of the n?1 switch elements is kept on or off according to a high or low voltage value out of set voltages of the output voltage, and all or any of the n synchronous rectification elements are selected to synchronously rectify pulse voltage of the secondary windings, and when operation with a high set value of the output voltage stops, a synchronous rectification element used to output the high set value performs switching operation until the output voltage goes down to the low voltage value of the set voltages of the output voltage.

Abstract: A switching power supply device that switches setting of an output voltage based on an external signal according to one or more embodiments includes: a transformer including a primary winding and n secondary windings; n synchronous rectification elements provided, corresponding to the n secondary windings; and n?1 switch elements that switch the secondary windings. Each of the n?1 switch elements is kept on or off according to a high or low voltage value out of set voltages of the output voltage, and all or any of the n synchronous rectification elements are selected to synchronously rectify pulse voltage of the secondary windings, and when operation with a high set value of the output voltage stops, a synchronous rectification element used to output the high set value performs switching operation until the output voltage goes down to the low voltage value of the set voltages of the output voltage.

Abstract: A switching power-supply device has an inductor, a switching element serially connected to the inductor, a control circuit, which controls on and off of the switching element and performs an output voltage control in any one of a plurality of modes including a continuous mode and a discontinuous mode, and a continuous mode detection circuit, which detects that the output voltage control is performed in the continuous mode when a current flowing through the switching element is equal to or greater than a threshold.

Abstract: A switching power-supply device has a smoothing capacitor connected between a ground-side output terminal connected to one end of a secondary winding of a transformer and a non-ground-side output terminal connected to the other end of the secondary winding; an N-type transistor connected between the non-ground-side output terminal and the other end of the secondary winding; a capacitor connected to a connection point of the N-type transistor and the other end of the secondary winding; a charging circuit connected between a connection point of the N-type transistor and the non-ground-side output terminal and the capacitor and configured to charge the capacitor, and a control circuit configured to perform on-and-off control of the N-type transistor by using a voltage of the capacitor.

Abstract: The present invention supplies desired DC output power to a first LED load and a second LED load whose color temperature is different from that of the first LED load, includes a switching element, ripple current reducers series-connected to the respective LED loads and for reducing current ripples flowing through the LED loads, and a control circuit for controlling the DC output power so that it has a predetermined value, by performing on-off control of the switching element based on a feedback voltage at a connecting point between each of the LED loads and a corresponding one of the ripple current reducers. Each ripple current reducer has feedback-type constant current control circuits for performing control for varying impedance, and the present invention also includes color controllers for performing color control by maintaining a total LED current value of the first and second LED loads at a certain value.

Abstract: A switching power-supply device has an inductor, a switching element serially connected to the inductor, a control circuit, which controls on and off of the switching element and performs an output voltage control in any one of a plurality of modes including a continuous mode and a discontinuous mode, and a continuous mode detection circuit, which detects that the output voltage control is performed in the continuous mode when a current flowing through the switching element is equal to or greater than a threshold.

Abstract: A switching power-supply device has a smoothing capacitor connected between a ground-side output terminal connected to one end of a secondary winding of a transformer and a non-ground-side output terminal connected to the other end of the secondary winding; an N-type transistor connected between the non-ground-side output terminal and the other end of the secondary winding; a capacitor connected to a connection point of the N-type transistor and the other end of the secondary winding; a charging circuit connected between a connection point of the N-type transistor and the non-ground-side output terminal and the capacitor and configured to charge the capacitor, and a control circuit configured to perform on-and-off control of the N-type transistor by using a voltage of the capacitor.

Abstract: The present invention includes: a converter configured to convert the direct-current voltage of the rectifier to another direct-current voltage and supply to a load; a peak hold unit configured to hold a peak value of a current detected by a current detecting unit configured to detect a current flowing in the switching element; an averaging unit configured to convert, to a current, an output of an n/2 output unit, and then integrate and output the converted current, the n/2 output unit configured to output n/2 (n is an integer of 1 or more) of the held peak value only in a regeneration current period of the reactor; a control unit configured to turn the switching element on and off based on an output signal of the averaging unit in such a way that an average current value of a current flowing in the reactor is equal to a predetermined value.