A LED driver chip open circuit detection circuit

Abstract

The invention discloses an open-circuit detection circuit for an LED driving chip, which belongs to the technical field of circuits. The open circuit detection circuit of the LED driver chip includes an open circuit detection digital circuit and an open circuit detection analog circuit. The open-circuit detection digital circuit records the position information of the open-circuit LED light on the rising edge of the clock GCLK according to the input enable signal EN, reset signal RST, and open-circuit signal OPEN, processes the output PWM, and shields the output display of the open-circuit LED in the next sub-cycle. The open circuit detection analog circuit judges whether its working state is open circuit according to the OUT signal of the LED light, and generates an open circuit signal OPEN and transmits it to the open circuit detection digital circuit, and at the same time resets the OPEN signal that has been judged to be in an open circuit state. The invention solves the problem of the open cross on the small-pitch LED display screen, reduces the detection complexity, improves the detection accuracy, reduces the power consumption of the circuit, and reduces the area of ​​the circuit, and has been 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.

Images