Abstract: Disclosed is a constant current drive for an LED light source, including a main power supply loop and at least one backup power supply loop. The main power supply loop at least includes a power conversion circuit. The power conversion circuit outputs a constant current to an LED light source. The backup power supply loop at least includes a power conversion backup circuit. The power conversion backup circuit outputs a constant current to the LED light source. When the power conversion circuit and the power conversion backup circuit operate normally, any one thereof operates in a nominal state or a derating state, and the output ends thereof are connected in parallel and then supply power to the LED light source simultaneously. When any one of the power conversion circuit and the power conversion backup circuit is invalid, the invalid circuit will not affect the normal operation of the remaining circuit.

Abstract: An auxiliary power supply circuit of a two wire dimmer, comprising: an auxiliary source capacitor (20) and a cutoff switch (30) constituting a series branch, a chopper switch (10) parallel-connected to the series branch, and a control device (40) connected to the chopper switch (10) and to the cutoff switch (30). The control device (40) measures an auxiliary source voltage and receives a chopper voltage control signal (Vg), and outputs signals (V1 and V2), on the basis of the result of a comparison between the auxiliary source voltage and a preset voltage and of the state of the chopper voltage control signal (Vg), to control the on and off of the chopper switch (10) and of the cutoff switch (30) for controlling the charging of the auxiliary source capacitor (20). The auxiliary power supply circuit has low losses, high efficiency, and is not limited by minimum chopper angle, and has low electromagnetic interference.

Abstract: A device and system for load driving. The device includes: an electric energy supplying unit including at least two units with output voltage adjustable; a sampling unit, with the input thereof connected to either end of a load unit for sampling the current of that end and sending the sampled current to an output voltage controller; the output voltage controller, with the input thereof connected to the output of the sampling unit for outputting voltage control signal to each unit with output voltage adjustable, according to the sampled current, so as to control the difference between the output voltage of each unit with output voltage adjustable and the maximum load voltage in a load branch to be not greater than a preset difference threshold, with the difference threshold being greater than or equal to zero. The device and system for load driving can improve the reliability of the driving device and can reduce the complexity of the circuit.

Abstract: A load driving device and system, and a limiting point control method and device. The load driving device comprising: a voltage/current regulative main circuit placed under the control of an output current controller, for use in conducting a voltage conversion on an input voltage, and in supplying electric power to a subsequent load unit; a sampling unit connected to an output terminal of the main circuit, for use in sampling an output feature parameter of the main circuit; the output current controller, for use in controlling a limiting point of the main circuit, and on the basis of the adjustment direction of the limiting point and on changes of the output feature parameters of the main circuit before and after an adjustment, determining a steady working point for the main circuit, and controlling the main circuit to work at the steady working point. The load driving device and system enable an increase in driver reliability and a reduction in circuit complexity.

Abstract: A multi-path constant current driving circuit. In the multi-path constant current driving circuit, a current sharing transformer (T31, T32, T33, T3(n?1)) is provided in power supply circuits which are provided with adjacent rectifier and filter units (Z31, Z32, Z33, Z3n). A first winding of the current sharing transformer (T31, T32, T33, T3(n?1)) is connected between a first terminal of a secondary winding of a first power supply circuit and the rectifier and filter unit (Z31, Z32, Z33, Z3n) of the first power supply circuit. A second winding of the current sharing transformer (T31, T32, T33, T3(n?1)) is connected between a first terminal of a secondary winding of a second power supply circuit and the rectifier and filter unit (Z31, Z32, Z33, Z3n) of the second power supply circuit. In-phase current flows through the dotted terminal of the first winding and the synonym terminal of the second winding of the current sharing transformer (T31, T32, T33, T3(n?1)).

Abstract: Provided in an embodiment of the present invention are an LED driver, and method and device for controlling the fixed value of the LED driver, the method comprising: detecting whether an existing terminal of an LED driver inputs a control signal; when the control signal is detected, determining the fixed value of the LED driver according to the control signal; when the LED driver is an LED driver having no dimming function, the fixed value is the rated current of the LED driver; when the LED driver is an LED driver having a dimming function, the fixed value includes the upper limit or lower limit of the output current value of the LED driver. The method, device and the LED driver provided in the embodiment of the present invention can save LED driver costs.

Abstract: A constant-current Light Emitting Diode (LED) driver circuit is provided, and the circuit includes: an output voltage adjustable circuit and at least one path of LED load, wherein the output voltage adjustable circuit comprises: a switch converting main circuit, an output characteristic parameter sampling circuit, and an output voltage controller.

Abstract: A power adapter, including an AC input terminal, an AC-DC power converter, a DC-DC power converter, and an output terminal, wherein the AC-DC power converter and the DC-DC power converter are separate components, and wherein the power AC input terminal, AC-DC power converter, DC-DC power converter and the output terminal are connected sequentially via a plurality of cords.

Abstract: The present invention discloses a high efficiency constant current LED driver, which comprises a rectification bridge, a PFC main circuit, an isolated DC/DC converter, a PFC controller and a PFC bus control circuit. Since the input voltage is an intermediate PFC bus voltage, which varies with the output voltage of the DC/DC converter. When the isolated DC/DC converter is an LLC resonant circuit, the operating frequency of the LLC circuit is close to the resonant frequency within a wide output voltage range. Thus, the gain range and the operating frequency is narrow, and can enable the constant current module to work with a high efficiency at a wide output voltage range. When the isolated DC/DC converter is a symmetric half bridge, or an asymmetric half bridge or a full bridge circuit, the duty cycle of DC/DC circuit is close to 50% within a wide output voltage range. Thus, the changing range of the duty cycle of the DC/DC converter will be narrow and can improve the efficiency dramatically.

Abstract: Disclosed is a constant current drive for an LED light source, including a main power supply loop and at least one backup power supply loop. The main power supply loop at least includes a power conversion circuit. The power conversion circuit outputs a constant current to an LED light source. The backup power supply loop at least includes a power conversion backup circuit. The power conversion backup circuit outputs a constant current to the LED light source. When the power conversion circuit and the power conversion backup circuit operate normally, any one thereof operates in a nominal state or a derating state, and the output ends thereof are connected in parallel and then supply power to the LED light source simultaneously. When any one of the power conversion circuit and the power conversion backup circuit is invalid, the invalid circuit will not affect the normal operation of the remaining circuit.

Abstract: A LED lamp system including an electric linker, a heat conducting liquid, a hollow cooling system with an outer surface, a hollow chamber through which a heat conducting liquid is located, and a hollow cavity separate from the hollow chamber, at least one LED, an interface connected to the hollow cooling system and to the at least one LED, and a power supply connected between the electric linker and the interface.

Abstract: A constant current control circuit with multiple outputs for a LED driver, the circuit including a single-output constant current power supply, and multiple output circuits, each output circuit comprising a current sharing circuit, a current sharing control circuit and a LED load. The LED load and the current sharing circuit are in series and form a series loop with a first terminal and a second terminal of the series loop connected to a first output terminal and a second output terminal of the constant current power supply.

Abstract: A circuit to improve the power factor of a power supply at light load, the circuit including a rectifier bridge, a filter positioned before or after the rectifier bridge, a logic control and power drive circuit, a switching transistor, a light load detecting circuit configured to output a control signal to the logic control and power drive circuit which controls the switching transistor to conduct when a heavy load is experienced and to cut off when a light load is experienced, in order to control the working status of the filter capacitor, and a power factor correction circuit.

Abstract: An auxiliary power supply circuit of a two wire dimmer, comprising: an auxiliary source capacitor (20) and a cutoff switch (30) constituting a series branch, a chopper switch (10) parallel-connected to the series branch, and a control device (40) connected to the chopper switch (10) and to the cutoff switch (30). The control device (40) measures an auxiliary source voltage and receives a chopper voltage control signal (Vg), and outputs signals (V1 and V2), on the basis of the result of a comparison between the auxiliary source voltage and a preset voltage and of the state of the chopper voltage control signal (Vg), to control the on and off of the chopper switch (10) and of the cutoff switch (30) for controlling the charging of the auxiliary source capacitor (20). The auxiliary power supply circuit has low losses, high efficiency, and is not limited by minimum chopper angle, and has low electromagnetic interference.

Abstract: A multi-path constant current drive circuit includes a DC/AC converter, a main transformer and at least two rectifying and filtering units. The main transformer includes at least one assistant side winding with a tap; together with the assistant side winding of the main transformer, each of the at least two rectifying and filtering units respectively forms a power supply loop; each power supply loop includes a first rectifying loop and a second rectifying loop, which are relatively used for the rectification of the positive and the negative half-cycle alternating voltage; a current-equalizing transformer is arranged between the adjacent first power supply loop and second power supply loop, the windings of the current-equalizing transformer are respectively in the rectifying loops contained in the first power supply loop and the second power supply loop, thus realizing the current equalization between the different rectifying loops in which the adjacent rectifying and filtering units are contained.

Abstract: The present invention discloses a high efficiency constant current LED driver, which comprises a rectification bridge, a PFC main circuit, an isolated DC/DC converter, a PFC controller and a PFC bus control circuit. Since the input voltage is an intermediate PFC bus voltage, which varies with the output voltage of the DC/DC converter. When the isolated DC/DC converter is an LLC resonant circuit, the operating frequency of the LLC circuit is close to the resonant frequency within a wide output voltage range. Thus, the gain range and the operating frequency is narrow, and can enable the constant current module to work with a high efficiency at a wide output voltage range. When the isolated DC/DC converter is a symmetric half bridge, or an asymmetric half bridge or a full bridge circuit, the duty cycle of DC/DC circuit is close to 50% within a wide output voltage range. Thus, the changing range of the duty cycle of the DC/DC converter will be narrow and can improve the efficiency dramatically.

Abstract: A load driving device and system, and a limiting point control method and device. The load driving device comprising: a voltage/current regulative main circuit placed under the control of an output current controller, for use in conducting a voltage conversion on an input voltage, and in supplying electric power to a subsequent load unit; a sampling unit connected to an output terminal of the main circuit, for use in sampling an output feature parameter of the main circuit; the output current controller, for use in controlling a limiting point of the main circuit, and on the basis of the adjustment direction of the limiting point and on changes of the output feature parameters of the main circuit before and after an adjustment, determining a steady working point for the main circuit, and controlling the main circuit to work at the steady working point. The load driving device and system enable an increase in driver reliability and a reduction in circuit complexity.

Abstract: A device and system for load driving. The device includes: an electric energy supplying unit including at least two units with output voltage adjustable; a sampling unit, with the input thereof connected to either end of a load unit for sampling the current of that end and sending the sampled current to an output voltage controller; the output voltage controller, with the input thereof connected to the output of the sampling unit for outputting voltage control signal to each unit with output voltage adjustable, according to the sampled current, so as to control the difference between the output voltage of each unit with output voltage adjustable and the maximum load voltage in a load branch to be not greater than a preset difference threshold, with the difference threshold being greater than or equal to zero. The device and system for load driving can improve the reliability of the driving device and can reduce the complexity of the circuit.

Abstract: A LED drive circuit for SCR dimming including an external controller configured to receive AC voltage from a power network to convert the AC voltage to an AC voltage with a lacked phase by phase controlling the voltage through a thyristor, and a LED driver that includes a bridge rectifier configured to shape the AC voltage with the lacked phase output into a unidirectional pulse DC voltage, and a phase angle detecting circuit configured to shape the AC voltage signal output with lacked phase from the external controller into a saw-tooth wave pulse signal.

Abstract: Provided are a method, apparatus and system for controlling a light source. The method comprises: acquiring an adjustment signal and determining a dimming item according to the adjustment signal; the dimming item being composed of the value and/or value range of at least one characteristics parameter of a pulse drive signal; converting the adjustment signal into the pulse drive signal indicated by the dimming item; controlling an adjustment switch by means of the pulse drive signal, so as to output a voltage including a chopped wave voltage corresponding to the dimming item, thereby transmitting adjustment information about the colour and/or brightness of the light source by means of the voltage including the chopped wave voltage. The method, apparatus and system can achieve the function of adjusting the colour and/or brightness of the light source.