A noise reduction circuit for a matrix LED driver includes a pseudo random number generator, an up counter, a clock module, and a plurality of matrix switch controllers. The matrix switch controllers and the up counter randomly change a power-on sequence applied across matrix switches in the matrix LED driver according to working random numbers generated by the pseudo random number generator. The circuit prevents jitter-induced noise from periodically reoccurring at the power source of the matrix LED driver, thereby reducing noise energy.

A noise reduction circuit for a matrix LED driver includes a pseudo random number generator, an up counter, a clock module, and a plurality of matrix switch controllers. The matrix switch controllers and the up counter randomly change a power-on sequence applied across matrix switches in the matrix LED driver according to working random numbers generated by the pseudo random number generator. The circuit prevents jitter-induced noise from periodically reoccurring at the power source of the matrix LED driver, thereby reducing noise energy.

A light-emitting diode (LED) driver configured to generate an LED driving current based on an input signal may include a terminal exposed to outside, a controller configured to identify a first identifier and data from the input signal, identify a second identifier based on a signal applied to the terminal, and when the first identifier and the second identifier are identical to each other, generate a control signal based on the data. The LED driver further may further include a current source configured to generate the LED driving current based on the control signal.

A light-emitting diode (LED) driver configured to generate an LED driving current based on an input signal may include a terminal exposed to outside, a controller configured to identify a first identifier and data from the input signal, identify a second identifier based on a signal applied to the terminal, and when the first identifier and the second identifier are identical to each other, generate a control signal based on the data. The LED driver further may further include a current source configured to generate the LED driving current based on the control signal.

A method of controlling a pattern skin lighting device for a vehicle is provided. The method includes generating a plurality of random numbers and accumulating the number of continuous turn-on times for each lightening cell in an arrangement of the lightening cells configuring a pattern skin lighting device. Additionally, the method includes selecting a turn-on target lightening cell, lightening cells having an accumulative value of the number of continuous turn-on times that is a predetermined reference value or less, among the lightening cells corresponding to the generated random number, and turning on a light emitting element of the selected turn-on target lightening cell.

A method of controlling a pattern skin lighting device for a vehicle is provided. The method includes generating a plurality of random numbers and accumulating the number of continuous turn-on times for each lightening cell in an arrangement of the lightening cells configuring a pattern skin lighting device. Additionally, the method includes selecting a turn-on target lightening cell, lightening cells having an accumulative value of the number of continuous turn-on times that is a predetermined reference value or less, among the lightening cells corresponding to the generated random number, and turning on a light emitting element of the selected turn-on target lightening cell.

A serial LED driver with a built-in calibratable parameter transmits a grayscale vector, a calibration parameter matrix or an appropriate current value vector and includes: a nonvolatile memory receiving and storing the calibratable parameter; a calibration matrix processing unit reads elements corresponding to the LED lamp bead and being pre-stored in the calibration parameter matrix of the nonvolatile memory, receives the grayscale vector, and performs matrix computation according to the grayscale vector and the calibration parameter matrix to generate a new grayscale vector; and a pulse width modulation circuit, which outputs a constant current to the LED lamp bead according to the first new grayscale vector to adjust the LED lamp bead; or outputs another corresponding constant current to adjust the LED lamp bead according to the new grayscale vector and the appropriate current value vector corresponding to the LED lamp bead and being pre-stored in the nonvolatile memory.

A load regulation device, such as an LED driver, may be configured to control the intensity of a light source based on an analog control signal and a preconfigured dimming curve. The LED driver may sense a magnitude of the analog control signal and determine a new low-end and/or high-end control signal magnitude that falls outside of the input signal range of the dimming curve. The LED driver may rescale the preconfigured dimming curve according to new low-end and/or high-end control signal magnitudes and dim the light source based on the rescaled dimming curve. Multiple LED drivers controlled by the same analog control signal may communicate with each other regarding the magnitude of the analog control signal sensed by each LED driver, and match their target intensity levels despite sensing different analog control signal. A controller may be provided to coordinate the operation of the multiple LED drivers.

A load regulation device, such as an LED driver, may be configured to control the intensity of a light source based on an analog control signal and a preconfigured dimming curve. The LED driver may sense a magnitude of the analog control signal and determine a new low-end and/or high-end control signal magnitude that falls outside of the input signal range of the dimming curve. The LED driver may rescale the preconfigured dimming curve according to new low-end and/or high-end control signal magnitudes and dim the light source based on the rescaled dimming curve. Multiple LED drivers controlled by the same analog control signal may communicate with each other regarding the magnitude of the analog control signal sensed by each LED driver, and match their target intensity levels despite sensing different analog control signal. A controller may be provided to coordinate the operation of the multiple LED drivers.

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.