SparkFun Forums

[jamesmccain]

Does anyone have any suggestions (or products) that has a barrel power jack (female) to JST connector (female) for a uno?

I just bought a 3.7V 6aH battery that has a female JST connector and a have an Arduino UNO (SMD) that only has usb and barrel jack. Being the idiot I am, I didn't realize the uno didn't have a JST connector.

[jamesmccain]

no ideas/suggestions?
It appears I'll have to makeshift a connector myself?!

[jyoung]

You say you've got a 3.7v battery for a Uno? That's not high enough. Minimum input voltage for a Uno is 6v. You'll need two of those batteries in series.

But yes, unless you can find an adapter cable somewhere (I doubt it), you'll need to make one. The Uno's power connector is a 2.1mm center positive barrel jack.

[Longhorn Engineer]

Take the board to Radioshack or Fry's. They should have some jacks. Just test fit a couple then solder up a cable. I think they also sell wall adapters if you don't have any spare ones.

The UNO board is going to need at least 7V to operate. No more then 9V. 7-9V. Make sure it can supply at minimum 500mA.

[WizenedEE]

No more then 9V.

Incorrect. It can do up to 20V, but they recommend not much more than 12V.

As for OP, solder is cheaper than custom cables and shipping. Just use heatshrink so it'll stay together and not short things out.

[jamesmccain]

You say you've got a 3.7v battery for a Uno? That's not high enough. Minimum input voltage for a Uno is 6v. You'll need two of those batteries in series.

But yes, unless you can find an adapter cable somewhere (I doubt it), you'll need to make one. The Uno's power connector is a 2.1mm center positive barrel jack.

yet again, another flaw I overlooked and in the mist of correcting. ::sigh:: thanks again...


however, I did find this (http://www.sparkfun.com/products/10287), which I then can make a connector to the battery JST connection (of the new battery).

[trialex]

If and when you move forward to making your project permanent, and start using just the bare mega chip as opposed to the whole arduino board, you can power it off just the 3.7V battery. There are a few complicting factors, such as being outside the technical limit for running at 16MHz (although many have "overclocked" it like this and run it OK for non life threatening applications) , and interfacing with sensors or other equipment that is designed to run at 5V only.

If you are just doing simple stuff with LEDs, or using 3.3V devices (which are becoming more and more the norm), running everything at the lower voltage definitely has advantages in terms of efficiency.