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 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 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.

An illumination device having a light-emitting diode field and an adjustable current source for each LED. The current source delivers a pulse width modulated current having a pulse height. An open-loop/closed-loop controller is provided for the open-loop/closed-loop control of the brightness of the LEDs. A setpoint value for the pulse height can be produced for the current source. A brightness value can be specified for each LED in accordance with the setpoint value, encoded in a video signal, and provided at a video signal output. The light-emitting diode field has a decoder, which is connected to the video signal input and via which the brightness value can be decoded from the video signal and converted into a duty cycle with which the pulse height can be produced;

An illumination device having a light-emitting diode field and an adjustable current source for each LED. The current source delivers a pulse width modulated current having a pulse height. An open-loop/closed-loop controller is provided for the open-loop/closed-loop control of the brightness of the LEDs. A setpoint value for the pulse height can be produced for the current source. A brightness value can be specified for each LED in accordance with the setpoint value, encoded in a video signal, and provided at a video signal output. The light-emitting diode field has a decoder, which is connected to the video signal input and via which the brightness value can be decoded from the video signal and converted into a duty cycle with which the pulse height can be produced;

A display module is provided. In the display module, a liquid crystal display panel has a plurality of display subareas. A color backlight module has a plurality of backlight subareas in a one-to-one correspondence to the plurality of display subareas. A driving apparatus may sequentially drive liquid crystal molecules in the display subareas to turn over, and after driving the liquid crystal molecules in each display subarea to turn over, drive a light-emitting element of one color included in each backlight source in one corresponding backlight subarea to emit light.

A controller pulse width modulation (PWM) controls multiple light-emitting pixels arranged in an array that form a variable light distribution lamp. A common counter is provided in common for the multiple light-emitting pixels, and generates a common count value having a ramp waveform. A signal processing unit generates multiple duty cycle instruction values for specifying the duty cycles of the multiple light-emitting pixels according to a light distribution instruction. Furthermore, the signal processing unit stores multiple offset values that correspond to the multiple light-emitting pixels, generates an individual count value for each light-emitting pixel by adding the corresponding offset value to the common count value, and generates individual PWM signals pwml through pwmn that correspond to results of comparison between the individual count values and the corresponding duty cycle instruction values.

A controller pulse width modulation (PWM) controls multiple light-emitting pixels arranged in an array that form a variable light distribution lamp. A common counter is provided in common for the multiple light-emitting pixels, and generates a common count value having a ramp waveform. A signal processing unit generates multiple duty cycle instruction values for specifying the duty cycles of the multiple light-emitting pixels according to a light distribution instruction. Furthermore, the signal processing unit stores multiple offset values that correspond to the multiple light-emitting pixels, generates an individual count value for each light-emitting pixel by adding the corresponding offset value to the common count value, and generates individual PWM signals pwml through pwmn that correspond to results of comparison between the individual count values and the corresponding duty cycle instruction values.

A dual-line cascade application system for simultaneously supplying electrical power and transmitting data, including a controller, cascade chips connected to the controller, and LED lights connected to the cascade chips. Each cascade chip is provided with a voltage clamp module, an electrical power supply module, a data storage module, a PWM constant current output driving circuit, an R end (Red LED output end), a G end (Green LED output end), a B end (Blue LED output end), a W end (White LED output end), a VCC/DATA end and a GND/DATA end, as well as a data sampling and calibration module, a power line data sampling and transmission module, a chip initial address setting by command module, a module which determines if E-fuse address of the chip is identical to an address of received data, and an E-fuse module which are sequentially connected. A method using the system is also provided.