A lighting apparatus includes a bridge circuit, a current source, a first LED module, a second LED module and a switch. The bridge circuit is used for rectifying an input AC power to generate a DC power. The current source receives the DC power to generate a driving current. The first LED module emits a first light of a first color temperature. The second LED module emits a second light of a second color temperature. The switch is coupled to the current source to change at least a resistance parameter corresponding to a current ratio between the first LED module and the second LED module to generate a mixed light of a mixed color temperature.

The present disclosure relates to an LED driving technology. According to the present disclosure, it is possible to increase the fineness of the gray scale without increasing a frequency of a clock by combining a plurality of driving current sources to generate a driving current supplied to one driving line.

The present disclosure relates to an LED driving technology. According to the present disclosure, it is possible to increase the fineness of the gray scale without increasing a frequency of a clock by combining a plurality of driving current sources to generate a driving current supplied to one driving line.

Disclosed herein is a method of optical pulse emission including three phases. During a first phase, a capacitor is charged from a supply voltage node. During a second phase, a voltage stored on the capacitor is boosted, and then the capacitor is at least partially discharged through a light emitting device. During a third phase, the capacitor is further discharged by bypassing the light emitting device. The third phase may begin prior to an end of the second phase.

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.

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.

A current driving circuit configured to drive a light-emitting device is provided. The current driving circuit includes a first current generating circuit, a second current generating circuit and a driver circuit. The first current generating circuit is configured to generate a reference current. The second current generating circuit includes at least one variable resistor, and may generate a compensation current according to the at least one variable resistor. The at least one variable resistor is selected from at least one of a positive TCR resistor and a negative TCR resistor. The driver circuit is coupled to the first current generating circuit and the second current generating circuit, and configured to receive the reference current and the compensation current to serve as a driving current. The driver circuit outputs the driving current to drive the light-emitting device.

An embodiment LED driver system comprises a power transistor configured to be selectively activated for generating a driving current for an array of LEDs, the power transistor having a first conduction terminal coupled to the array of LEDs and a second conduction terminal coupled to a reference resistor; an operational amplifier having a non-inverting input for receiving a reference voltage, an inverting input coupled to the second conduction terminal of the power transistor, and an output terminal coupled to a first conduction terminal of a transmission gate having a second conduction terminal coupled to a control terminal of the power transistor and a control terminal for receiving an enable signal; and a slew rate control unit configured to control the slew rate of the driving current.

An embodiment LED driver system comprises a power transistor configured to be selectively activated for generating a driving current for an array of LEDs, the power transistor having a first conduction terminal coupled to the array of LEDs and a second conduction terminal coupled to a reference resistor; an operational amplifier having a non-inverting input for receiving a reference voltage, an inverting input coupled to the second conduction terminal of the power transistor, and an output terminal coupled to a first conduction terminal of a transmission gate having a second conduction terminal coupled to a control terminal of the power transistor and a control terminal for receiving an enable signal; and a slew rate control unit configured to control the slew rate of the driving current.

A light emitting diode (LED) circuit is disclosed having an LED having a plurality of current paths. A controller may be included for controlling the LEDs. The LED is connected to a first transistor and a first current sink to drive a constant current through the LED through a first current path. At least one cloning transistor can establish a parallel current path through the LED and parallel to the first current path and is connected such that the constant current in the first current sink is duplicated in the parallel current path.