7 segment display problem


I have a 7 segment display: http://www.gotronic.fr/pj-322.pdf and when I send a value to the arduino to show on the display they all lit up when at the right time but one of them is not as bright as all the other ones, any idea how I can fix this if I connect it to 5v directly it does it right so it must be the board, I have an Adruino Mega 2560 and I use pins 52 tp 45 (for the DP aswell.


At the very end of the link you provided, there is a brief sketch showing a "recommended" and an "invalid" set-up. They are showing that you should use a separate resistor for each segment rather than use one resistor for all the segments.

The forward voltage is listed as 2.5 volts. If you connect 5 volts across a segment without a resistor to limit the current, you're risking permanent damage to the display.


But I have a resistor for every segment.. And some of them are working like they should. So I still don't have the solution for it.

Thank you for the reply btw

Are all the pins set to OUTPUT?

I am doing it from a library, so I think it is.

Maybe you can isolate the problem a little.

If you’ve got an additional LED, you could replace the first one and see if the problem is duplicated.

Check that all the resistors have the same value.

In your original post, you mentioned applying 5 volts directly. I cautioned you about doing this without a resistor but you’ve clarified that you had resistors in the proper locations. If it’s possible to remove the leads from the Arduino to the resistors, is it then possible to apply the 5 volts to each segment in turn to see if the brightness is constant for all segments. If it is not, I don’t think the Arduino is the problem. On the other hand, if the contrast is similar for all segments then we’ll address that next.