A minimum voltage detector circuit is disclosed. The circuit includes a plurality of LED strings each having a plurality of series-coupled LEDs. The minimum voltage detector circuit is configured to detect a minimum voltage from among the plurality of LED strings, and also to perform open/short detection among the plurality of LED strings. The minimum voltage detector circuit includes a plurality of voltage comparators and correspondingly coupled replica circuits. Each of the voltage comparators includes an amplifier having a first input coupled to a cathode of a last LED of one of the plurality of LED strings, an output, and a second input coupled to the output. Each voltage comparator further includes a replica circuit coupled to the amplifier. The replica circuit is configured to maintain an output transistor of the amplifier in an active state when the amplifier is in an unbalanced state.

A circuit arrangement for the electrical wiring of a light unit of a headlight for a vehicle, having a control unit which is connected to a power supply, the light unit having at least one semiconductor light source and a temperature measurer, wherein the semiconductor light source has a cathode and wherein the temperature measurer has a cathode, and wherein the light unit has an equipotential bonding contact. In the light unit, the cathodes are electrically connected to one another and/or at least one of the cathodes is electrically connected to the equipotential bonding contact in the light unit.

A circuit arrangement for the electrical wiring of a light unit of a headlight for a vehicle, having a control unit which is connected to a power supply, the light unit having at least one semiconductor light source and a temperature measurer, wherein the semiconductor light source has a cathode and wherein the temperature measurer has a cathode, and wherein the light unit has an equipotential bonding contact. In the light unit, the cathodes are electrically connected to one another and/or at least one of the cathodes is electrically connected to the equipotential bonding contact in the light unit.

An LED tube lamp comprises: a glass lamp tube; an LED light strip disposed inside the glass lamp tube and comprised a mounting region and a connecting region; an LED module comprised a plurality of LED light sources mounted on the mounting region; two first connecting pads arranged on the connecting region, each of the first connecting pads comprising a through hole therein; a fixing structure disposed inside the glass lamp tube and extending along the longitudinal direction of the glass lamp tube, the fixing structure comprising a first end fixedly connected to the inner circumferential surface of the glass lamp tube and a second end fixedly connected to the LED light strip; a circuit board separate from the light strip and soldered to the LED light strip via the two first connecting pads, and a solder be disposed on each of the first connecting pads and in the through hole of each first connecting pad and a power supply module. The power supply module comprises a first rectifying circuit; a filtering circuit coupled to the first rectifying circuit and a driving circuit coupled to the filtering circuit.

A 2-Wire LED dimming system and method re-purposes existing 120V AC architecture and hardware to carry low voltage PWM gradient DC power to the LED lamps provides a consistent gradation over a 0-100% dimming range. An LED Driver is electrically connected to an AC power source and connect to at least one LED lamp. The AC power source is electrically connected to an AC to DC converter where the AC power is converted to filtered and regulated DC power for the control unit and the power switch. The power switch is electrically connected to the AC to DC converter DC power output. The control unit is electrically connected to the power switch which is turned ON or OFF according to the pulse width modulation PWM signal from the control unit in order to connect or disconnect the DC power from the AC to DC converter.

A 2-Wire LED dimming system and method re-purposes existing 120V AC architecture and hardware to carry low voltage PWM gradient DC power to the LED lamps provides a consistent gradation over a 0-100% dimming range. An LED Driver is electrically connected to an AC power source and connect to at least one LED lamp. The AC power source is electrically connected to an AC to DC converter where the AC power is converted to filtered and regulated DC power for the control unit and the power switch. The power switch is electrically connected to the AC to DC converter DC power output. The control unit is electrically connected to the power switch which is turned ON or OFF according to the pulse width modulation PWM signal from the control unit in order to connect or disconnect the DC power from the AC to DC converter.

System and method for regulating one or more currents. The system includes a system controller, an inductor, a first resistor, a switch and a first diode. The system controller includes a first controller terminal and a ground terminal, the system controller being configured to output a drive signal at the first controller terminal. The inductor includes a first inductor terminal and a second inductor terminal, the first inductor terminal being coupled to the ground terminal, the second inductor terminal being coupled to one or more light emitting diodes. The first resistor includes a first resistor terminal and a second resistor terminal, the first resistor terminal being coupled to the ground terminal. The switch is configured to receive the drive signal and coupled to the second resistor terminal. The first diode includes a first diode terminal and a second diode terminal and coupled to the first resistor.

A light source driving device performs a switching control on a third switch of a second control unit by using a control signal of a fourth control unit (overvoltage protection circuit), so as to allow the third switch to be turned on by the control signal of the fourth control unit only in a partial section in which an overvoltage occurs, and then turns off the third switch, thereby quickly releasing the blocking of light emission from the light source so as to be capable of returning to a light emitting state.

A light source driving device performs a switching control on a third switch of a second control unit by using a control signal of a fourth control unit (overvoltage protection circuit), so as to allow the third switch to be turned on by the control signal of the fourth control unit only in a partial section in which an overvoltage occurs, and then turns off the third switch, thereby quickly releasing the blocking of light emission from the light source so as to be capable of returning to a light emitting state.

A method for droop control in a DC system comprising a DC source, a DC bus and at least two DC application devices. Each application device having a droop curve and the DC source providing a DC voltage over the DC bus to each application device. Each application device performs a first voltage measurement during a first load condition and performs a second voltage measurement during a second load condition. Each application device adjusts its respective settings of the droop curve in accordance with the first and second voltage measurements.