SSD1306 brightness is low even at max value

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Yakeru
 
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Joined: Wed Feb 25, 2015 2:45 pm

SSD1306 brightness is low even at max value

Post by Yakeru »

Hello,

I am currently working with the adafruit 128x32 SSD1306 display plugged to an Atmega328p (no arduino bootloader, dev. in C with atmel studio, making my own lib) and I have an issue with the contrast/brightness of the display.

I managed to send various commands to the SSD1306 via SPI and to change the contrast, turn all pixels on or send data to display things etc.. but even with a 0xFF value for the contrast it's really not that bright, I don't see a big difference with a contrast a 50% or 100%.

At the beginning I thought that the power supply was too weak, since I am powering the SSD1306 directly with outputs from the Atmega, but according to the datasheet, even with all pixel on it draws less than a mA, and the Atmega can provide way more than that. Plus I tried turning on just a few pixels and it doesn't change anything.

Then I tested u8glib to control the screen, and it's way brighter with the same power source.

So I was wondering if I was missing something in the config or various commands to send to the SSD1306 to get the full brightness. I don't see what I missed when reading the datasheet.

Can anybody help me on that ?

Thanks,

Yakeru

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adafruit_support_rick
 
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Re: SSD1306 brightness is low even at max value

Post by adafruit_support_rick »

I recommend looking at the adafruit SSD1306 library to see what commands are sent to initialize the display.

Also, I think you must have read the OLED panel datasheet wrong - it will draw a max of 8.5mA with all pixels lit. The display datasheet also shows the startup and shutdown sequences you must follow.

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Yakeru
 
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Re: SSD1306 brightness is low even at max value

Post by Yakeru »

Hello Rick,

You're right, I ended up reading adafruit's lib and found what I forgot to do :-)
And for the current draw I will check again for the 8,5 mA, it was probably the current draw from the controller that I found and not from the screen itself.
Anyways, it stays way under what the Atmega can provide so it should be ok.

Thank you,

Yakeru

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