Arduino Compatible TFT LCD module (HCMODU0043)

[enrfbezo]

Hi Andrew
This is working great thank you very much all the colours are normal now .

Regarding the backlight. It still looks like it needs a big "boost" of some sort. Do you have any tips?

[andrew]

Thanks for confirming, I'll get this added to the first post for anyone else who has this problem.

With regards to the backlight, the only thing I can suggest is a small modification to the module. On the back of the module there is a small black surface mount resistor marked 331. If you where to change this to something slightly lower such as a 220 ohm resistor, this will improve the backlight. I've check this by simply adding the resistor across the 330R and it made an improvement in brightness. Backlight current consumption increased from 4mA to 8mA. I'm going to contact the factory and speak to them about this. I do however have to make the disclaimer that any modification like this to the board will invalidate its warranty so if you do choose to modify it you do so at your own risk.

[enrfbezo]

Hi Andrew,
I've tried as you suggested but i thought it was still very dimmed so instead i put 110ohm resistors between the 5V and the pin of the BL resistor and it's working great so far. Your support was great however I must say when i buy a shield like this i expect to use it on a plug and play basis. Anyway I've got 4 more of those screens to modify now arrrg
Thank you again,
Frederic.

[andrew]

Keep in mind that if you do connect a resistor in the way you suggested, instead of across the 330R resistor, you will lose the functionality of the BL control pin. If you don't care about backlight control another option is to simply bypass the transistor that controls the backlight. This will gain you the extra volts lost across the collector-emitter junction of the transistor and should make a noticeable difference. Please also be careful not to increase the current to the backlight by much more than its default current as too much current can shorten it's life. I should also point out that my suggestions are simply in answer to your question of how to improve contrast, and that you do have the option of returning any item your not happy with (assuming of course that it was purchased from us) so long as it's not been modified. As mentioned before, I am however going to try and contact the factory that manufactures these modules to see if it safe to boost the brightness of the backlight beyond what the factory has fixed it to.