Ard. Uno R3 wrong output value to 5V pin(Uno Board malfunctioning?)

I am trying to use my Arduino Uno R3 with a 12VDC 2A main power adapter feed to the board. The VIN connector is outputting 11.46VDC, the 2 GND are fine and the 5V is outputting 7.14VDC, and the 3.3V connector is outputting 3.29V.

Is my board done?

The reason I was testing this is because it has fried 2 of my DS3231 boards not realizing that it is feeding too much power.

I tested this on my Arduino Leonardo and the voltages output are proper.

I would say you have fried a voltage regulator.

What were you using for the power supply ?
Also is it a real or clone Arduino as it matters for the voltage regulator.

It is a real Arduino Uno R3.

I am using the 12vdc to power A4988(stepper driver) and the 5vdc to power the VCC side of the stepper driver and to power a DS3231(Real time clock module).

  • by using the Vin pin I am able to avoid using additional wiring and connectors.

┬┐Can I replace the voltage regulator?

If you have both the equipment and expertise the YES you can replace it.

However if you look at the posts of people wo have done this then you will see the milage varies as there is a chance other components were taken out too.

Note for REAL Arduinos...There are a lot of posts that mention the VR blowing at around the 12 volt mark.
Clones seem more tolerant but it is preferable to run Real ones at 7 to 10 volts to prolong the VR circuitry.

Upon closer inspection I can see there is some distortion on the top of the VR chip. I have ordered a replacement. Since it seems like it was still functioning otherwise I will replace the chip. They should arrive by the weekend. I will update with the outcome after replacement.