Multi-line scanning high-refresh-rate full-color LED driving chip and driving method

Abstract

The invention discloses a multi-line scanning high-refresh-rate full-color LED driving chip and a driving method, and belongs to the field of full-color LED driving chip design. The multi-line scanning high-refresh-rate full-color LED driving chip comprises a synchronous controller, a shift register, a state register, an SRAM buffer, a gray clock generation module, a driving module, a pre-charging circuit and an analog output module. The gray scale clock generation module is used for carrying out frequency multiplication / frequency division processing on the data clock signal DCLK according to the instruction information so as to generate a gray scale clock signal GCLK for controlling the gray scale. The driving module is used for counting the gray scale clock signal GCLK to obtain gray scale counting corresponding to each row of pixel data, and generating an output waveform of a PWM signal corresponding to each row of pixel data by using N continuous rows of pixel data and the corresponding gray scale counting in each scanning process, so that multi-row scanning is realized. The analog output module is used for receiving the PWM signal and generating constant current to drive the LED lamp bead in cooperation with the pre-charging circuit. According to the chip, the refresh rate can be improved, and more scanning lines can be supported.

Description

technical field [0001] The invention belongs to the field of full-color LED driver chip design, and more specifically relates to a full-color LED driver chip with multi-line scanning and high refresh rate and a driving method. Background technique [0002] LED (Light Emitting Diode) was born in the 1960s. After more than 50 years of development, the power consumption of LED is getting lower and lower, and the effective brightness is getting higher and higher. At the same time, it has long life, high-speed response, low Low cost, green and environmental protection, etc., are more and more widely used in the fields of traditional lighting display, aerospace and consumer products. Thanks to the advantages of LED's good spatial extension, consistency, and seamless splicing, LED screens perform well in the field of large-screen display inside and outside, and as the size of LED lamp beads continues to decrease, the pixel density of LED screens continues to increase. increase, it...

AI Technical Summary

Problems solved by technology

In order to ensure that the LED has a good row gray level, when SPWM divides the sub-cycle, the number of gray clocks (GCLK) in a single sub-cycle cannot be too small, and due to the limitation of the PCB wiring frequency of the LED screen, within one frame time The total number of GCLKs is limited, and in traditional LED driver chips, the grayscale clock signal is provided by an off-chip signal through pins, so that the visual refresh rate and line scanning capability are mutually restricted under the condition of high grayscale display. , it is impossible to achieve high visual refresh rate and multi-line scanning at the same time in practical applications

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