Semiconductor Components Industries, LLC

Fairchild Korea Semiconductor Ltd.

Hyun-Chul Eum

Young-Jong Kim

In-Ki Park

Tae-Sung Kim

Sung-Won Yun

Taesung Kim

Seung-Uk Yang

Doo-Yong Jung

Young-Mo Yang

Woo-Kang Jin

Kyung-Oun Jang

Eung-Woo Lee

Wonseok Lim

Yong-Sang Shin

Chi-Yin Lo

A circuit includes an overshoot-and-undershoot (OU) signal generator generating a signal indicating detection of an overshoot or an undershoot of an output signal of the power converter. The circuit further includes a feedback signal modulator receiving a first feedback signal and the signal indicating detection of the overshoot or the undershoot and generating a second feedback signal in response to the first feedback signal and the signal indicating detection of the overshoot or the undershoot. The feedback signal modulator generates the second feedback signal that is different from the first feedback signal during a predetermined time interval after the signal indicating detection of the overshoot or the undershoot has been asserted.

Controlling output voltage for power converter

A light emitting diode (LED) driver circuit includes an LED string and a conducting state detection circuit. The conducting state detection circuit detects a conducting state of the LED string, and generates a discharge control signal upon sensing that the LED string is in a non-conducting state. A current source generates a discharge current according to the discharge control signal when the LED string is in the non-conducting state. A passive bleeder provides current compensation by internal regulator operation. An LED spike current suppression circuit suppresses spike current that can occur when the input voltage increases above a threshold. A bias supply circuit has an input capacitor that provides a bias voltage.

LED driver circuit and LED driving method

A circuit includes an overload monitor comparing a current sense signal to a threshold signal to generate a comparison result and adjusting a value of a first count signal in response to the comparison result and a monitoring signal. The monitoring signal indicates a time interval during which the overload monitor adjusts the value of the first count signal. The circuit further includes an overload protection signal generator generating an overload protection signal in response to the first count signal, the overload protection signal indicating whether the power converter is operating in an overload condition.

Overload protection for power converter

A circuit comprises an amplifier and a plurality of channels, the plurality of channels including respective transistors. The respective transistors of the channels control respective magnitudes of respective currents of the channels according to an output of the amplifier. The respective transistors of the plurality of channels may be included in an auto-commutated circuit. A first Light Emitting Diode (LED) circuit may be coupled between a power source and a first channel of the plurality of channels. A second LED circuit may be coupled between the first channel and a second channel of the plurality of LED channels. The power source may provide rectified Alternating Current (AC).

Multiple linear regulation

A method includes generating a gain transition signal in response to any one of an average value of a feedback signal, a slope of the feedback signal, a slope of an input signal of the power converter, a maximum value of the input signal, and a minimum value of the input signal, and generating a first gain control signal and a second gain control signal in response to the gain transition signal. A gain transition controller includes a transition signal generator generating the gain transition signal and a gain control signal generator generating the first gain control signal and the second gain control signal in response to the gain transition signal.

System and method for controlling output signal of power converter

A power factor correction circuit corrects a filter current flowing through a filter capacitor asymmetrically based on a peak of an input voltage by controlling a switching operation of a power switch, thereby correcting distortion of an input current.

Power factor correction circuit and driving method thereof

A method includes comparing a value of a current sense signal indicating an output signal of a power converter to a value of a threshold signal, adjusting a value of a first count signal in response to the comparison result, and determining whether or not the power converter is operating in an overload condition using the first count signal. A circuit includes an overload monitor comparing a value of a current sense signal to a value of a threshold signal, adjusting a value of a first count signal in response to the comparison result, and determining whether or not the power converter is operating in an overload condition using the first count signal. The circuit further includes an overload protection signal generator generating an overload protection signal indicating whether or not the power converter is operating in the overload condition.

An LED driving device includes an LED string including at least first and second LED elements connected in series, first and second channels coupled to output nodes of the first and second LED elements, respectively, first and second regulators to regulate a current flowing through the first and second channels in response to first and second control voltages, respectively, and a control voltage generating circuit to generate the first and second control voltages based on a difference between a reference voltage and a comparative voltage, the comparative voltage being generated based on a sensing voltage, the sensing voltage corresponding to an LED current flowing through the LED string. The control voltage generating circuit includes a reference voltage generator to generate the reference voltage based on an input voltage and the dimming signal, the input voltage being supplied to the LED string, the dimming signal controlling dimming of the LED string.

LED driving device

A method for controlling a power converter includes receiving an input signal through an input node and generating an intermediate signal using a capacitor, generating a control signal in response to the input signal and the intermediate signal, coupling or decoupling the input node and the capacitor in response to the control signal, and generating an output signal in response to the intermediate signal. A circuit for controlling a power converter includes an input node receiving an input signal, a first capacitor providing an intermediate signal, a detection circuit generating a control signal in response to the input signal and the intermediate signal, a switching device coupling the input node and the first capacitor in response to the control signal, and a regulator generating an output signal in response to the intermediate signal.

System and method for controlling switching device in power converter

A method includes generating a first feedback signal in response to a tracking signal indicating an output signal of the power converter. The method further includes detecting an overshoot of the tracking signal or an undershoot of the tracking signal, generating a second feedback signal in response to the detection result and the first feedback signal, and generating a modulation signal in response to the second feedback signal. A circuit includes an overshoot-and-undershoot (OU) signal generator detecting an overshoot of a tracking signal or an undershoot of the tracking signal. The circuit further includes a feedback signal modulator receiving a first feedback signal and generating a second feedback signal in response to the detection result and the first feedback signal and a modulation controller generating a modulation signal in response to the second feedback signal.

A method includes generating a first gain control signal and a second gain control signal in response to a gain transition signal indicating a transition of a power converter from a first gain mode to a second gain mode. The method further includes causing the power converter to enter the first gain mode in response to the first gain control signal, and causing the power converter to enter the second gain mode in response to the second gain control signal. A circuit includes a gain transition controller generating a first gain control signal and a second gain control signal in response to a gain transition signal, and a gain control circuit causing the power converter to enter the first gain mode in response to the first gain control signal and causing the power converter to enter the second gain mode in response to the second gain control signal.

According to the exemplary embodiments, a short-circuit of a sense resistor is detected according to a result of comparison between a sense voltage and a reference voltage at a time based on at least one of a period set based on an input sense voltage and a turn-on time of a power switch. A blanking period is set based on the input sense voltage in a current mode, and a short-circuited resistor detection period is set based on the input sense voltage.

Sensing resistor short determiner, switch control circuit including the same and power supply including the switch control circuit

A LED driving device is provided, which includes a LED string including at least one LED element, at least one channel connected to the at least one LED element, a current regulator configured to regulate a current flowing through the at least one channel according to at least one corresponding control voltage, and a control signal generating circuit configured to generate a control signal based on a difference between a reference voltage and a comparative voltage. The comparative voltage is determined based on a sensing voltage, and the sensing voltage corresponds to an LED current flowing through the LED string. The control signal generating circuit is further configured to generate the at least one corresponding control voltage based on the control signal.

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Seoul, South Korea

Hyun-Chul Eum