STM32F746G-DISCO Display brightness

[giorgio23]

Posted on November 01, 2016 at 09:41

Hello,

Is it possible to control the brightness of the display?

Thanks again

Giorgio

#stm32f746g-disco

[Tesla DeLorean]

Posted on November 02, 2016 at 21:44

The schematic in the

http://www.st.com/content/ccc/resource/technical/document/user_manual/f0/14/c1/b9/95/6d/40/4d/DM00190424.pdf/files/DM00190424.pdf/jcr:content/translations/en.DM00190424.pdf

has LCD_BL_CTRL connected to PK3, perhaps you can modulate that?

[Walid FTITI_O]

Posted on November 03, 2016 at 11:35

Hi guglielmino.giorgio, 

After checking both STM32F746G-DISCO

http://www.st.com/content/ccc/resource/technical/document/user_manual/f0/14/c1/b9/95/6d/40/4d/DM00190424.pdf/files/DM00190424.pdf/jcr:content/translations/en.DM00190424.pdf

and the

http://www.st.com/content/ccc/resource/technical/document/datasheet/5b/92/e8/f8/41/e5/43/59/CD00098098.pdf/files/CD00098098.pdf/jcr:content/translations/en.CD00098098.pdf

 :

The ''Iled'' which monitors the Leds current (brightness) is set to 20 mA as maximum value through setting the Rled= 8 ohm as typical value (R75 on disco) and Rset= 100Kohm as maximum value ( R82 on disco).

The device can be turned ON/OFF through the logic enable signal pin EN which is connected to LCD_BL_CTRL ( PK3 On MCU)

You can either control this ''Iled'' By applying a low frequency PWM signal to LCD_BL_CTRL to decrease the Led current. I propose that you put the input signal through the 0ohm resistor R81. The PWM signal can be brought from another pin out by external connection.

-Hannibal-