How does the Controller Board for 7.0 TFT screen utilize the PWM Backlight Control

------Question for NHD-7.0-800480EF-20 Please Put your question below------

I am utilizing the NHD-7.0-800480EF-20 to prototype a board that includes the SSD1963QL9 to drive a 7.0" LCD screen. In the datasheet for the SSD1963QL9, it mentions the use of the PWM output pin to have variable control over the LCD backlight. According to the datasheet for the NHD-7.0-800480EF-20, the PWM output pin of the SSD1963QL9 does not appear to be connected to any output pins of the NHD-7.0-800480EF-20, nor is there any mention of variable backlight control.

My question is: Are there internal connections to the PWM pin that control the output of the backlight anode and cathode? If so, are there specifications regarding how the PWM output affects the backlight?

Welcome to the forum.

AFAICT, that controller board does not support the driver IC’s PWM variable brightness function for the backlight.


Agreed with Paul that the board does not appear to support the IC’s brightness control function, but instead seems to expose the control line for the backlight drive apparatus on the input connector J2.

A few minutes with some magnification and a continuity checker should be enough to validate that idea for oneself, and figure out how the boost converter/backlight drive is set up. Most likely the user input is a plain old enable function, making backlight brightness proportional to PWM duty cycle.

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Ok, thanks for the opinion. I will move forward with that.