Abstract: A control circuit, comprising a protection detection circuit, a protection synchronous output circuit, a protection synchronous input circuit and a protection circuit, is provided. The protection detection circuit is adapted to generate an error notice signal when detecting an error condition. The protection synchronous output circuit is coupled to the protection detection circuit far enabling a level of a protection synchronous pin to be a protection level when receiving the error notice signal. The protection synchronous input circuit is coupled to the protection synchronous pin for generating a synchronous protection signal when the level of the protection synchronous pin has been at the protection level for a predetermined time period. The protection circuit generates a protection signal to make the control circuit enter a protection mode when receiving one of the error notice signal and the synchronous protection signal.

Abstract: An LED driving circuit comprises a converting circuit, a current regulator, a converting controller and a low dimming protection blocking circuit, is disclosed. The converting circuit is adapted to perform a power conversion to provide a driving voltage for lighting an LED module. The current regulator is coupled to the LED module for regulating a current flowing through the LED module. The current regulator conducts and stops conducting the current flowing through the LED module according to a dimming signal, and executes a protection process when the LED module operates abnormal. The converting controller controls the power conversion of the converting circuit according to a voltage level of at least one connection node of the current regulator and the LED module. The low dimming protection blocking circuit stops the protection process of the current regulator when the driving voltage is lower than a predetermined value.

Abstract: A controller with a multi-function pin, adapted to control a converting circuit according to a control signal for converting an input voltage into an output voltage, is disclosed. The controller has the multi-function pin, an enable unit, an over-current detecting unit and a logic control unit. The enable unit is coupled to the multi-function pin for receiving an enable signal and activates the controller in response to the enable signal. The over-current detecting is coupled to the multi-function pin and determines an over-current value according to an over-current set resistance coupled between the multi-function pin and a voltage source. The over-current detecting unit generates an over-current protection signal according to the over-current value and a current flowing through the converting circuit. The logic control unit determines whether executing an over-current protection according to the over-current protection signal.

Abstract: A power-good signal generator generates a power-good signal according to a control signal of a controller, and comprises an impedance element, a controlled transistor and a power sequencing free circuit. An end of the impedance element is coupled to a second voltage source. The controlled transistor has first and second input/output ends and a controlled end, wherein the first input/output end is coupled to the other end of the impedance element to generate the power-good signal. An operating state of the controlled transistor is changed in response to the control signal. The power sequencing free circuit is coupled to the controlled end and one of the first input/output end and the second voltage source. When the second voltage source is supplied before the first voltage source, the power sequencing free circuit turns on the controlled transistor to clamp the power-good signal to be lower than a predetermined voltage level.

Abstract: A multi-phase DC-DC converter and a method of controlling a multi-phase DC-DC converter are disclosed. The multi-phase DC-DC converter is adapted to control a plurality of channels in a multi-phase DC-DC converting circuit for providing an output voltage. The multi-phase DC-DC converter comprises a constant on unit, a plurality of PWM units and a pulse width logic unit. The constant on unit determines a time point of generating a turning on signal indicative of a preset time period according to the output voltage. Each PWM unit generates a PWM signal, and a pulse width thereof is determined according to the turning on signal and currents of the channels. The pulse width logic unit controls the channels according to the corresponding PWM signals generated by the plurality of PWM units.

Abstract: The resonant converting circuit comprises a resonant circuit, a current detecting circuit and the resonant controller. The resonant controller controls a power conversion of the resonant circuit for converting an input voltage into an output voltage and the resonant controller comprises an over current judgment unit and an over current protection unit. The over current judgment unit determines whether the resonant current is higher than an over current value according to a current detecting signal generated by the current detecting circuit. The over current protection unit generates a protection signal in response to a determined result of the over current judgment unit and an indication signal indicative of an operating state of the resonant controller. The resonant controller executes a corresponding protecting process in response to the protection signal.

Abstract: The present invention provides an LED current balance apparatus, which utilities capacitances coupled to secondary windings of a transformer to store voltage differences between LED strings. Thereby, the driving voltages applied to LED strings are respectively modulated to make the LED strings flowing through a same driving current. A current regulating apparatus is coupled to all LED strings to stabilize total current of the LED strings at a predetermined current.

Abstract: A current detecting circuit detects a resonant current in a primary side of a resonant converting circuit to generate a current detecting signal. An output detecting circuit generates a feedback signal according to the output voltage. A resonant controller generates a clock signal and adjusts an operating frequency of the clock signal in response to the feedback signal for modulating the output voltage of the resonant circuit. The resonant controller includes a resonance deviation protection unit which detects the current detecting signal according to a phase of the clock signal to determine whether the resonant circuit enters a region of zero current switching or not. When the resonant circuit enters the region of zero current switching, the resonant controller executes a corresponding protection process in response to that the resonant controller operates in a starting mode or a normal operating mode.

Abstract: A driving controller for driving a load is disclosed. The driving circuit includes a driving power supply and the driving controller. The driving power supply provides a first power source to the load. The controller is coupled to a second power source to receive an electric power for operating. The controller controls the amount of the electric power to the load when operating in a first mode and stops the driving power supply from providing the electric power to the load when operating in a second mode. The controller operates exclusively in the first mode before the driving power supply provides the first power source to the load.

Abstract: A driving circuit controls a driving signal according to a control signal at a first or second logic level for driving a load. A driving protection circuit includes a driving signal detection circuit for generating a load error signal in response to that a load is abnormal; a delay judgment circuit coupled to the driving signal detection circuit for generating a first signal in response to that the load has been abnormal for a predetermined time period; and a logic control circuit coupled to the delay judgment circuit and the driving circuit for determining whether to modulate the driving signal according to the first signal. When the control signal has been at the first logic level and the load has been abnormal for the predetermined time period, the logic control signal modulates the driving signal to be a level corresponding to the control signal at the second logic level.

Abstract: An LED driving circuit with open-circuit protection is disclosed. The LED driving circuit pulls down an operation voltage supplied to a converting controller of the LED driving circuit when a voltage across an LED module of the LED driving circuit is too high, so as to stop the converting controller operating and further latch the converting controller at the protection state until that the converting controller is restarted or the condition of the voltage supplied to the LED module being too high is solved.

Abstract: A synchronous driving circuit in the arts may cause a short through pheromone when a duty cycle of a duty cycle control signal is too short. The present invention sets a delay time with a suitable period when the duty cycle of the duty cycle control signal is too short to avoid the short through phenomenon.

Abstract: An LED driving circuit for driving an LED module is provided. The LED module is coupled to an inductor and a flywheel unit to provide a continuous current conduction of the inductor. A terminal of a converting switch is coupled to the LED module, and another terminal thereof is coupled to ground through a current detection unit that generates a current feedback signal to a controller, so as to stabilize a current flowing through the LED module. The LED driving circuit also includes a protecting circuit, which detects a potential of one end of the LED module to generate a detection signal and makes/has the converting switch to be turned off responsive to the detection signal. If the converting switch is turned off, driving of the LED module is stopped.

Abstract: A control circuit adapted to a DC-DC converting circuit is disclosed. The controller comprises a reference voltage generator, a reference voltage adjusting circuit, a feedback circuit and a driving circuit. The reference voltage adjusting circuit generates an adjusted reference voltage according to a reference voltage generated by the reference voltage generator. The feedback circuit generates a feedback control signal according to the adjusted reference voltage and the feedback signal. The driving circuit generates at least one control signal for controlling the converting circuit according to the feedback control signal.

Abstract: A converting controller, adapted to control a converting circuit to convert an electric power from an input power source, is provided. The controller comprises a duty cycle control unit, a protection enabling control unit and a protection unit. The duty cycle control unit controls the converting circuit according to a feedback signal for converting the electric power from the input power. The protection enabling control unit outputs protection enabling signals according to time results of a timing circuit. The protection unit detects the converting circuit and generates a protection signal when any circuit error is determined, so as to stop the duty cycle control unit, wherein the protection unit has a plurality of protection functions and enables the protection functions with respect to the protection enabling signals, respectively.

Abstract: A constant on-time period of a DC to DC buck converting controller is adjusted according to a level of a preset output voltage. Therefore, the DC to DC buck converting controller of the present invention is suitable for any applications with different requests of output voltages or different operating mode.

Abstract: A power converting circuit and a feedback control circuit for the power converting circuit are disclosed. The feedback control circuit comprises a feedback controller and a level controlling unit. The feedback controller generates a feedback control signal according to a reference voltage signal and a feedback signal. The level controlling unit receives one of the reference voltage signal and the feedback signal and modules a level of the received signal from a first level to a second level with time according to a level adjusting signal.

Abstract: An LED driving circuit includes a first and a second LED modules, a first and a second switching converters, an extreme voltage detecting and selecting circuit, a current balance circuit and a controller. The first switching converter transforms electric power of an input power supply into a first output voltage for lighting the first LED module. The second switching converter transforms electric power of the input power supply into a second output voltage for lighting the second LED module. The current balance circuit balances the currents flowing through the first and the second LED modules. The extreme voltage detecting and selecting circuit detects the first and the second LED modules and selects to output one of detecting results. The controller controls the transforming of the first switching converter and the second switching converter to light the first and the second LED modules in response to the outputted detecting result.

Abstract: A controller with protection function, for controlling a transistor having a control terminal, a first terminal coupled to a load, a second terminal, is disclosed. The controller comprises a judgment unit and a current control unit. The judgment unit is coupled to the transistor and generates a current reducing signal when a potential of the first terminal of the transistor or a voltage difference between the first terminal and the second terminal of the transistor is higher than a preset value. The current control unit is coupled to the control terminal of the transistor for substantially stabilizing the current flowing through the transistor at a preset current value, and reduces the current flowing from the preset current value when receiving the current reducing signal.

Abstract: The present invention discloses an LED driving circuit and controller, capable of maintaining an average value of a current flowing through an LED module at a predetermined current value. The LED driving circuit and controller compensates influences of any factors deviating the average value of the current flowing through the LED module by modulating a period of constant on time or constant off time, or by modulating the determining value(s) of current peak value and/or current valley value according to a difference between an actual average value and the preset current value.