Olimex Support Forum

OLinuXino Android / Linux boards and System On Modules => A20 => Topic started by: vnv on June 10, 2022, 01:09:21 PM

Title: Powered my Lime board with 7V :( :(
Post by: vnv on June 10, 2022, 01:09:21 PM
Hi,

I have mistakenly powered my board with 7V instead of 5V :( :( :( :( :(

Yellow light was blinking, then I have removed 7V and put 5V back.
On header GPIO1 I have 5V and 3.3V but nothing comes out on serial port or HDMI.
Also this was my first run.

Is there any protection on the board, or it's the end?

Thank everyone in advance!
Title: Re: Powered my Lime board with 7V :( :(
Post by: LubOlimex on June 10, 2022, 01:18:48 PM
It is sometimes possible to survive 7V DC but it would depend on how long was 7V DC applied. Usually LIME boards have TVS resistor protection so you can repair it with the change of one component. Look at the schematic and near the 5V power jack and you will find the TVS.

Which Lime board exactly?
Title: Re: Powered my Lime board with 7V :( :(
Post by: vnv on June 10, 2022, 03:58:14 PM
@LubOlimex Tnx for helping out!


It was long enough :) (I would say couple of minutes)

I have measured 3.3v and 5v on the header, if diode is burnt shouldn't it be shorted to ground, I shouldn't be able to read 3.3 and 5v on the header? - or I am getting something wrong here?
(I got this by looking at the schematic)


Also, is there any boot screen which should be visible without sdcard - through serial or through hdmi? Or A20 needs to boot-up to be able to see some serial or screen output?

BR!








 
Title: Re: Powered my Lime board with 7V :( :(
Post by: vnv on June 10, 2022, 04:04:47 PM
Ok ... in all this mess... I must provide feedback for some unfortunate soul who will have same problems.

1. I have used 7V instead 5V  on the barrel connector --- DON'T DO IT!!! (some yellow LED flashes)

2. Diode doesn't gets burned (my case) - 3.3V and 5V on GPIO1 showed correct voltages

3. I have used Sandisk Industrial 16GB memory card -- IT DOESN'T WORK

3.1 I have used 128GB Sandisk Extreme pro -- ALL WORKS FINE

4. I have used USB to serial to monitor bootup -- When power applied you will see Linux bootup

5. HDMI was connected -- After bootup it shows desktop


Thank you for helping out LubOlimex!!

BR everyone!