LED display driving chip and application

Abstract

The invention discloses an LED display driving chip and application, and belongs to the technical field of integrated circuits and LED display crossing. In order to solve the problems that in the prior art, ultra-high-density LEDs such as Mini-LEDs need to balance the distribution relation of the display effect and the bit width, and the bit width is greatly limited under the display condition that the refresh rate is high, on the basis of an existing double-latch PWM chip architecture, the PAM and PWM hybrid modulation method is applied to a driving chip architecture, an existing PWM control mode is replaced, and better image gray scale uniformity in a small current mode is obtained; a DAC low-current accurate control circuit is adopted to obtain more accurate current output so as to meet the application performance requirements of ultra-high density LED display. Data can be processed to achieve a better driving effect, and the application performance requirement of ultra-high-density LED display is met.

Description

technical field [0001] The invention relates to the technical field of integrated circuits and LED displays, and more specifically, to an LED display driver chip and its application. Background technique [0002] With the development of the times, the requirements of electronic products for human-computer interaction are gradually increasing. Through the display screen, users can obtain information more intuitively and conveniently. Therefore, LED display screens are widely used in more and more usage scenarios. At present, LED display technology has gradually developed, and has transitioned from traditional display to Mini LED and even Micro LED display. Specifically, the density of sub-pixels per unit surface is getting higher and higher, so new requirements are put forward for display drivers. [0003] In the actual use of the LED driver chip, the LED unit at the corresponding position is often controlled by the column driver chip. Considering the size of the LED display...

AI Technical Summary

Problems solved by technology

When the bit width is larger, the display frequency is higher, and better display effect can be obtained, but when the bit width is too large, the clock pulse width will be narrower, so that it cannot be recognized in the circuit, resulting in the lack of chip integrity Or gray scale uniformity problem in low current mode

Therefore, in the scheme of modulating the image data signal by using the PWM method, it is necessary to balance the distribution relationship between the display effect and the bit width. Considering the performance of refresh rate and bit width

[0006] After retrieval, a Chinese patent application with a publication date of July 31, 2020, for a drive circuit for a display, application number CN202010402876.4, discloses a drive circuit for a display, wherein the control unit includes mutually independent PWM control unit and a PAM control unit, the PWM control unit is used to control the light-emitting time of the light-emitting unit, and the PAM control unit is used to control the size of the driving current in the light-emitting unit; the scheme controls the gate G of the MOS transistor through PAM Voltage, so as to realize pulse width adjustment, which will cause the MOS tube to fail to work normally when the voltage value is small, resulting in failure of setting, and the same point of PAM and PWM signal control will cause interference when the signal is inverted, which has a great impact on the actual effect

Another example is the Chinese patent application display panel and display panel driving method with the publication date of September 14, 2021, application number CN202080012789.6, which discloses a display panel comprising a plurality of pixels, including pulse width modulation (PWM ) to drive a first pixel circuit of a first light-emitting element in a plurality of light-emitting elements and a second pixel circuit for driving a second light-emitting element in a plurality of light-emitting elements through pulse amplitude modulation (PAM), which discloses a combination of PAM and PWM The method of controlling the LED display, but this scheme needs to be carried out in the order of PWM setting, PAM setting, PWM plus PAM modulation. The PAM and PWM control the same port and cannot be configured at the same time. It can only be configured in order according to the scanning results.

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