Mega's AMS 1117 5V Getting Hot with RAMPS 1.6 + 128*64 LCD

I have placed RAMPS 1.6 on my Arduino Mega Clone. When I feed RAMPS 1.6 with 12V 2A, the AMS 1117 component on Mega is getting hot. I might have attached fans to D9 and D10 in the wrong direction and gave it a try for a second. For testing, I have placed Adafruit Motor Shield on my Arduino Mega Clone and fed it with 12V 2A, the AMS 1117 component did not get hot.

Does this show that something is wrong with my RAMPS 1.6?
What do you think can be the problem?
I have a multimeter, which components should I test for discovering the damaged component?

Thank you.
bkarpuz

Note: The title changed after the discovery in the following post.

Edited 3 time(s). Last edit at 06/14/2023 12:06PM by bkarpuz.

Quote
bkarpuz
I have placed RAMPS 1.6 on my Arduino Mega Clone. When I feed RAMPS 1.6 with 12V 2A, the AMS 1117 component on Mega is getting hot. I might have attached fans to D9 and D10 in the wrong direction and gave it a try for a second. For testing, I have placed Adafruit Motor Shield on my Arduino Mega Clone and fed it with 12V 2A, the AMS 1117 component did not get hot.

Does this show that something is wrong with my RAMPS 1.6?
What do you think can be the problem?
I have a multimeter, which components should I test for discovering the damaged component?

Thank you.
bkarpuz

The problem occures when RepRapDiscount FULL GRAPHIC Smart Controller is attached to the board.

Edited 1 time(s). Last edit at 06/14/2023 11:53AM by bkarpuz.

I have made a detailled test and figured out that when I connect EXP2 on 128*64 LCD to CN2 on RAMPS 1.6, I get light on the LCD and the AMS1117 component of Mega starts heating up very fast.
What should I do in this case?

??
The display get power form exp1 and should light up when plugged into exp1

you don't even need exp2 for the lcd display itself to work. (you can leave exp2 unplugged and the display will light up and display things, but the encoder will not work)

Exp2 is used for the encoder left and right, the kill pin and IO required for the sdcard.

Edited 2 time(s). Last edit at 06/14/2023 09:00PM by Dust.

Quote
Dust
??
The display get power form exp1 and should light up when plugged into exp1

you don't even need exp2 for the lcd display itself to work. (you can leave exp2 unplugged and the display will light up and display things, but the encoder will not work)

Exp2 is used for the encoder left and right, the kill pin and IO required for the sdcard.

You are right, with only EXP1, I could get animations on the screen. It also works from the USB (without 12V 2A additional power supply).
With EXP2 connected and when only powered from the USB, I dont get any over heat on Mega's 5V regulator.
But when I attach 12V 2A additional power supply, Mega's 5V regulator gets hot immediately.

Under normal circumstances this should not happen, right?

... could be a "semi-short" somewhere or something is oszillating wildly.

Check for shorts or low resistance especially at the endstops.

Best methode for checking external loads is with unplugging them and mesuring the drawn current ... caution with th estepper drivers! - they could burn when plugging/unplugging the motors when powered.

---

Viktor
--------
Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

Quote
VDX
... could be a "semi-short" somewhere or something is oszillating wildly.

Check for shorts or low resistance especially at the endstops.

Best methode for checking external loads is with unplugging them and mesuring the drawn current ... caution with th estepper drivers! - they could burn when plugging/unplugging the motors when powered.

Even when there is no stepper drivers attached and no sketch is uploaded, I get heating when EXP2 and 12V 2A are plugged.

Which components do you think I should check and how?

Here are photos of the screen from the front and the back


and here is the multimeter I have


Edited 2 time(s). Last edit at 06/15/2023 10:25AM by bkarpuz.