Dose the ARDUINO MEGA 2560 only have 1 VIN pin?

Hi, Doing a project with the ARDUINO MEGA 2560 and have screen shield blocking the VIN pin, but need to use the 12v I'm going to be powering it with to also power a stepper motor, is the VIN pin broken out to anywhere else on the board, or am I going to have to get the soldering iron out on the underside and solder a wire in?

(deleted)

spycatcher2k:
Use the barrel jack connection.

Do you mean solder to the barrel jack connection rather than the VIN pin?

(deleted)

spycatcher2k:
Thats for YOU to work out! I have no idea what you have in your workspace!

Sorry, just trying to work out what YOU mean by "Use the barrel jack connection." in the context of my OP.

but need to use the 12v I'm going to be powering it with to also power a stepper motor,

A bit of unsolicited advice. Do not power the Mega through the Vin or the power jack. Powering through Vin or the power jack means that the Mega and all peripherals that are on the 5V rail are powered by the onboard 5V regulator. The on board 5V regulator is not heat sinked so will supply limited current before it overheats and shuts down. The recommend max power dissipation for the regulator is 1 Watt. With 12V into the regulator the max current is about 140 mA (1W / (12V - 5V)). The Mega uses around 50ma of that leaving less than 90mA (max) for everything else. I would use a buck converter to drop the 12V to 5V and connect that to the 5V on the Mega, bypassing the, weak, 5V regulator.

There is no way that the Mega regulator will power a stepper motor.

Thank you, that sounds like some sage advice!

What was said above is solid advice. The onboard regulator on the arduino boards cannot supply much current even in ideal conditions, and powering from 12v (meaning it has to dissipate 1.4x as much power as your project is using at 5v as heat) is far from ideal conditions.

I'm confused by your question about the barrel jack though - you would supply the power via a connector that you plug into the barrel jack. I guess you could solder to the bottom of it if you had to, but why?

DrAzzy:
I'm confused by your question about the barrel jack though - you would supply the power via a connector that you plug into the barrel jack. I guess you could solder to the bottom of it if you had to, but why?

Oh, because I wanted to power a stepper motor with 12V to the VMOT pin, so had planned to power the MEGA with a 12V into the barrel jack and take the 12V from VIN pin to the stepper drivers VMOT pin so the Arduino would be on 5V and the motor on 12V. But the LCD shield I'm using covers the VIN pin, so I asked if it was broken out to any anywhere else on the board and got the reply

spycatcher2k:
Use the barrel jack connection.

(deleted)

Depends on how beefy those steppers are, but yeah.

You also don't want to be throwing all that noise onto the power supply for the microcontroller (I mean, it might be okay... but it might not. I wouldn't be afraid to try it on a clone, though I would on an official board, since those are more vulnerable to abuse of the power rails)

Basically, you want to use the power supply circuitry on the arduino boards as little as possible >.<