open circuit detection circuit for an LED driving chip

Abstract

The invention discloses an LED driving chip open circuit detection circuit, and belongs to the technical field of circuits. The LED driving chip open circuit detection circuit comprises an open circuit detection digital circuit and an open circuit detection analog circuit. And the open circuit detection digital circuit records the position information of the open circuit LED lamp at the rising edge of the clock GCLK according to the input enable signal EN, the input reset signal RST and the input open circuit signal OPEN, processes the output PWM, and shields the output display of the open circuit LED at the next sub-period. The open circuit detection analog circuit judges whether the working state of the open circuit detection analog circuit is open or not according to the OUT signal of the LED lamp, generates an open circuit signal OPEN and transmits the open circuit signal OPEN to the open circuit detection digital circuit, and meanwhile resets the OPEN signal judged to be in the open circuit state. According to the invention, the open circuit cross problem of the small-spacing LED display screen is solved, the detection complexity is reduced, the detection precision is improved, the circuit power consumption is reduced, the circuit area is reduced, and the detection method is successfully applied.

Description

technical field [0001] The invention relates to the technical field of circuits, in particular to an open circuit detection circuit for an LED driving chip. Background technique [0002] As a new type of semiconductor lighting material, LED is widely used in lighting equipment, display screens and other electronic equipment due to its advantages of low power consumption, long life, small size, low cost, high efficiency and safety, and green and pollution-free. [0003] Small-pitch LED displays have the advantages of seamless splicing, natural and real colors, clear pictures, modular maintenance, and good display uniformity. Research hotspots. Multi-channel constant current LED driver chips have the advantages of good matching, precise current control, high grayscale display, and excellent display effects, and are widely used in small-pitch LED driver chips. [0004] In the small-pitch LED display, the multi-channel constant-current LED driver chip can achieve different gra...

AI Technical Summary

Problems solved by technology

[0005] The cross phenomenon caused by LED dead pixels is very troublesome to the end users of the display screen, especially in the design of high line scanning. In addition to the false lighting of the light points extending in the horizontal direction, the false lighting of the vertical light points will also increase with the scanning. And to extend, small-pitch screens often adopt a design higher than 16 lines of scanning. Once there is a bad LED pixel, the cross phenomenon will be quite obvious, resulting in flaws in the display screen and poor display effect.

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