Arduino Forum

Using Arduino => Installation & Troubleshooting => Topic started by: seirsan on Nov 10, 2018, 01:02 am

Title: 5v pin on Arduino mega 2560 is outputting 9v
Post by: seirsan on Nov 10, 2018, 01:02 am
Hello,

I just hooked my mega board using a 9v power supply connected to the vIn and ground.  In the course of troubleshooting something in the circuit I noticed that instead of the expected 5v the mega's 5v pin is outputting 9v.  After some testing it seems the 5v pin is just passing through whatever voltage is being supplied to the vIn.  The 3.3v pin is still outputting the proper voltage.  The digital io pins also seems to be putting out 9v as well.

Any suggestions?
Title: Re: 5v pin on Arduino mega 2560 is outputting 9v
Post by: DrAzzy on Nov 10, 2018, 02:00 am
Stop powering it through vin immediately. Regulator has failed, and as you sispected is just passing the input voltage through to the output. You have probably damaged the chip running it like that.
Title: Re: 5v pin on Arduino mega 2560 is outputting 9v
Post by: seirsan on Nov 10, 2018, 03:47 am
Thanks that was my diagnosis as well.  Thanks for confirming my suspicions.

-Seirsan