Arduino uno power output

Hi all.

I need to power 2 encoders and 1 Adafruit neotrellis board. All 5v

Questions

When powering the Uno board via usb, can i use the vin pin as out put?

Can less voltage than requiered damage an encoder? rather than 5v use the 3.5v

Thanks

You won't damage the encoder by applying less voltage.

Arduino reads 3.3V as HIGH so there wont be any problems I guess. You can test it on your own.

When powering the Uno board via usb, can i use the vin pin as out put?

No, it's a power input connector, not an output.

If you want 5V derived from the USB connection use the pin marked 5V on the connectors.

PerryBebbington:
If you want 5V derived from the USB connection use the pin marked 5V on the connectors.

Im already using the 5v output.

Moris526:
Im already using the 5v output.

Err, OK, why is that a problem? What is stopping you connecting 2 things to it? Or 3? As long as you only draw, not sure, maybe less that ~300mA (someone will suggest a more accurate figure) I don't see how that is a problem. Please clarify.

Moris526:
Can less voltage than requiered damage an encoder? rather than 5v use the 3.5v

Definitely no damage.

If it's a simple mechanical contact based encoder it'll work just fine. If it's based on electronic sensing, it may simply not work.

When powering over USB you should be able to get ~500 mA out of the pin, depending largely on what the USB source can deliver. Mind: when powering off USB the 5V pin will be at about 4.5V.

PerryBebbington:
Err, OK, why is that a problem? What is stopping you connecting 2 things to it? Or 3? As long as you only draw, not sure, maybe less that ~300mA (someone will suggest a more accurate figure) I don't see how that is a problem. Please clarify.

Oh. I dont have the board to make multiple conections to one output.....maybe thats why i didnt thought that.....but.....a friend lended me a soldering pen.......maybe......

Thanks

Hi,
You can power the encoder from the UNO 5v, but I think the Neo Trellis with 32 neopixels will need a separate supply.

3963_top_lit_ORIG_2018_10.jpg

Tom... :slight_smile:

3963_top_lit_ORIG_2018_10.jpg