A switched-mode power supply and an associated television are disclosed. The switched-mode power supply includes a rectifier circuit, a transformer, a constant voltage control circuit, a power management circuit, and a constant current control circuit. An output terminal of the rectifier circuit is coupled both to a power detection terminal of the power management circuit and to a power input terminal of the transformer. A controlled terminal of the transformer is coupled to a control terminal of the power management circuit. A constant voltage output winding of the transformer is coupled through the constant voltage control circuit to a feedback input terminal of the power management circuit. A constant current output winding of the transformer is coupled to the constant current control circuit via an LED load. The solution of the present disclosure has the advantage of low cost.

An LED lamp tube and driver circuit that is direct replacement for fluorescent tubes with or without ballasts, that works with standard AC high voltage current input, with high frequency pulse current input, or with lower voltage input. The tube is wired to receive the current that is input from any two electrode pins from among the pairs of pins at the ends of the tube, which house the driver circuitry. The input current is converted to DC through a rectifier circuit, is filtered of unwanted frequencies and voltage through a filter circuit, and is controlled with a step-down constant current circuit to drive an LED array within the tube. The circuits comprise current loops having at least one current transformer, at least one transistor, capacitors, inductors, and resistors and interacting with an integrated circuit.

The present invention discloses a television backlight driving device and the driving method thereof, the said television backlight driving device comprises: an AC-DC module and an LED driving module; when a power is on, the said AC-DC module transforms an input supplied AC power into a DC power before supplying to the backlight LED lightstrip; comparing to the existing backlight driving methods, there is no second process of DC-DC needed, saving a system cost of the power, and improving an efficiency of the system; when the LED driving module determines the detection current larger than the preset current but smaller than the first threshold, a constant-current output for LED current is controlled by adjusting the duty ratio; when the detection current is larger than the first threshold or smaller than the preset current, the LED driving module feeds back the detection current to the AC-DC module; the AC-DC module then controls the DC voltage according to the detection current; different methods for adjustment may save a power consumption, as well as achieving an effect of stabling the current output; it owns a simple circuit structure, and a high system reliability.

A device, system, process, and method of manufacturing provides use of at least two LED lighting sources to provide auxiliary component modules. Embodiments can be used in a variety of industries, including city street lamps, indoor lighting systems, lighting systems in automobiles, train lighting systems, tunnel lighting systems, building lighting systems, networked lighting systems, and other systems that could benefit from flexibility and ease in changing circuit components for time-based, usage-based, or fault-based detected situations.

A light-emitting diode (LED) driving device comprising: a rectifier configured to convert alternating current (AC) power to direct current (DC) power; a convertor including: a transformer including a primary-side winding connected to the rectifier; and a main switch connected to the primary-side winding of the transformer; a controller configured to output a control signal to the main switch in response to a feedback signal; and an output modifier configured to modify the feedback signal.

An integrated circuit device is configured to drive multiple LED strings. The device includes a switch mode power supply control circuit configured to generate primary and secondary power transistor control signals and receive at least one current sense signal and an output voltage sense signal. The device also includes an output compare circuit configured to generate a plurality of pulse width modulated signals and a logic circuit configured to generate signals for selecting a reference voltage and for activating an absorber mode. The signal for activating an absorber mode is to be shared with the secondary power transistor control signal. The logic circuit is to be synchronized with the output compare module.

A light-emitting-diode-driving device includes a control circuit that is configured to perform constant current control with a DC-DC converter so that a value of a current detected by a current detection unit agrees with a prescribed reference current value to be supplied to a light source. The control circuit includes a reference-current-instruction unit, a threshold-voltage-setting unit, and a comparator circuit. The reference-current-instruction unit is configured to set the prescribed reference current value. The threshold-voltage-setting unit is configured to set a threshold voltage for determining a short circuit failure in the light source. The comparator circuit is configured to compare, with the threshold voltage, a value of a voltage that is detected by a voltage detection unit. The control circuit is configured to make the threshold-voltage-setting unit reduce the threshold voltage, when the reference-current-instruction unit reduces the prescribed reference current value.

An electronic lighting system with a driver for providing light from visible light bulbs and non-visible light bulbs, including from infrared, ultraviolet, LED and fluorescent lamps of multiple sizes and wattages, having power factor correction, surge protection, current sensing, current adjustment feedback, and dimming system. There are transformers dedicated to particular lamp receptacles that include interloper diodes and resistor sets that fine tune the functioning of the driver sensing loads. Comparator circuitry receives an external control signal and compares it to feedback from the output side of the circuitry, and thereby controls the Pulse Width Modulation circuitry, which cooperates with feedback-based transistors and a MOSFET gate driver circuit for current limiting to the loads being applied.

An electronic lighting system with a driver includes transformers that are dedicated to particular lamp receptacles that include interloper diode and resistor sets that fine tune the functioning of the driver. A buck converter and power factor correction, and a zeta scan are included. A comparator circuitry receives an external control signal and compares it to feedback from the output side of the circuitry, and thereby controls a Pulse Width Modulation (PWM) circuitry, which cooperates with feedback-based MOSFETs and a MOSFET gate driver circuit. This aids in dimming capabilities, recognizes and corrects for outages and recognizes and corrects for changes in the different size lamps that a user may install.

A DC-to-AC inverter provides power to a DC-to-AC converter via an isolation transformer. The DC-to-AC converter drives a DC load. A sensing circuit on the primary side of the isolation transformer senses the current flowing through the primary winding of the transformer. A capacitor is connected across the primary winding in parallel with the magnetizing inductance of the primary winding to form a parallel L-C combination. The capacitance of the capacitor is selected with respect to the magnetizing inductance such that the parallel L-C combination resonates at a nominal steady-state operating frequency of the DC-to-AC inverter, which causes the current through the primary winding to be proportional to a current through the DC load. The current through the primary winding is sensed and provided as a feedback signal to the DC-to-AC inverter to cause the DC-to-AC inverter to adjust the operating frequency to maintain the current at a desired magnitude.