A tube lamp including a light source including at least one string of light emitting diodes within a tube body; end caps having pin contacts on each end of the tube body; and driver electronics including a filament detector portion provided by a passive resistance capacitor (RC) circuit that simulates the filament load of a fluorescent lamp when installed into a ballast containing fixture. The tube lamp may also include a switch for selecting light characteristics for light emitted by the light source.

A light emitting device includes: a base member having a first surface including a first region; a first electric terminal including a first pin hole, the first pin hole penetrating the base member along a thickness direction of the base member; a second electric terminal including a second pin hole, the second pin hole penetrating the base member along the thickness direction; a first frame provided on the base member and surrounding the first region; a plurality of light emitting elements provided on the base member in the first region; a light-transmissive first member provided inward of the first frame, and covering the plurality of light emitting elements; and a protective element positioned between the base member and the first frame in the thickness direction. When viewed in a direction from the first pin hole toward the second pin hole, the protective element is positioned between the plurality of light emitting elements and the first pin hole and between the plurality of light emitting elements and the second pin hole.

Examples are disclosed that relate to monitoring an emission state of light sources. One example provides a light emitting circuit comprising a power source, one or more light sources connected to an output of the power source, and a control circuit comprising a pulsed voltage source and a control transistor configured to regulate a current through the light sources based upon an output of the pulsed voltage source. The light emitting circuit further comprises a monitor transistor comprising a gate connected to an output of the light sources such that a voltage at the output of the light sources controls an output of the monitor transistor, and a monitor transistor detector connected to the output of the monitor transistor. The monitor transistor detector is configured to monitor a state of the one or more light sources based upon a state of the output of the monitor transistor.

System and method for controlling one or more light emitting diodes. For example, the system includes: a power supply controller configured to receive a cathode voltage from a cathode of a diode, the diode including an anode configured to receive a rectified voltage generated by a rectifying bridge, the power supply controller being further configured to generate a first signal based at least in part on the cathode voltage; and a driver configured to receive the first signal and generate a second signal based at least in part on the first signal, the driver being further configured to output the second signal to a gate terminal of a transistor, the transistor including a source terminal coupled to the driver and a first resistor, the transistor further including a drain terminal coupled to the one or more light emitting diodes and an output capacitor connected to the cathode of the diode.

A driving circuit includes a first transistor, a capacitor, a second transistor, and a driving transistor. The first transistor is configured to provide a data signal according to a first scan signal. The capacitor is coupled to the first transistor, and the capacitor includes a first terminal and a second terminal. The second transistor is coupled to the first transistor, and the second transistor is configured to provide a start signal according to the data signal. The driving transistor is coupled to the second transistor, and the driving transistor is configured to output a driving signal according to the start signal.

A display device and a driving method thereof are provided. The display device includes a display panel, a controller, and a driver. The display panel includes a plurality of light-emitting elements. The controller receives characteristic information of the light-emitting elements, and obtains a first relationship curve between current density information and luminous efficiency information according to the characteristic information. The controller obtains a second relationship curve between duty cycle information and accumulated current consumption information or accumulated power consumption information according to the first relationship curve. The controller finds a selected duty cycle corresponding to a maximum luminous efficiency according to the second relationship curve. The driver activates the light-emitting elements according to the selected duty cycle.

An LED tube lamp comprises: a glass lamp tube; a light diffusion layer disposed on a surface of the glass lamp tube; an LED light strip, which comprises a fixing portion and an extending portion disposed in the glass lamp tube; a plurality of LED light sources mounted on the fixing portion of the LED light strip; a fixing structure disposed between the fixing portion and the inner circumferential surface the glass lamp tube; a power supply module disposed on the fixing structure and electrically connecting to the LED light strip and two end caps attached to two ends of the glass lamp tube respectively. The fixing structure comprises a first end fixedly connected to the inner circumferential surface of the glass lamp tube and a second end fixedly connected to the fixing portion of the LED light strip and not connected to the extending portion of the LED light strip.

Micro light-emitting diode display driver architectures and pixel structures are described. In an example, a driver circuit for a micro light emitting diode device includes a current mirror. A linearized transconductance amplifier is coupled to the current mirror. The linearized transconductance amplifier is to generate a pulse amplitude modulated current that is provided to a set of micro LEDs connected in parallel to provide fault tolerance architecture.

An electronic module comprising an input capacitor connected between a first and second node; a first and second switch connected in series between the first and second node and the second node, in parallel with the input capacitor, and defining an intermediate node at their interconnection; a voltage regulator configured for receiving power from the input capacitor and for providing output power at a configurable voltage (out) between an output node and the second node. A multi-output power supply system comprising three such modules. A LED-driver comprising such module. A multi-color LED driver comprising three modules. A solid state lighting device comprising three modules and three LEDs.

An electrical circuit for providing led light bulb drivers with the necessary electrical load for most triac and digital dimmer switches and provide dimming control to mimic incandescent light bulbs is described herein. The electrical circuit includes a non-linear electrical load circuit that is electrically coupled to a rectified alternating current (AC) input power source and providing the necessary load current to initiate and maintain activation of triac and digital dimmer switches. A phase sense and amplifier circuit is also coupled to the rectified AC input power source and it senses the AC input voltage phase, then transmits a control signal to the light emitting diode (LED) driver to adjust the current level of the power being delivered to the LEDs in a manner to mimic the dimming of incandescent light bulbs.