Barrel Jack to 2-pin JST

Two pin JST connector to a 2.1x 5.5mm barrel jack, 6.25 inch long jumper cable. We use this cable to adapt from a wall power supply to a relatively small, SMD JST connector. We found that many of the SMD connectors used for battery charging were too large or were not capable of through-putting the current we wanted for faster charging. This setup, with a SMD JST connector and wall power supply, can handle up to 2A!

Barrel Jack to 2-pin JST Product Help and Resources

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Looking for answers to technical questions?

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  • -------------------- Tech Support Tips/Troubleshooting/Common Issues --------------------

    JST Series?

    The two pin connector on this product is compatible with polarized JST PH Series connector.

  • Which is positive(Power) and negitive(Gnd).

  • J.R. / about 10 years ago / 1

    Hi Sparkfun, both connectors are polarized but I don't see which pin connects to which. Cool cable, but please let us which pin on the JST corresponds to the pin on the barrel jack. Perhaps a diagram would be useful?

    • MikeGrusin / about 10 years ago / 1

      Hi J.R., this adapter has the same polarity as all of our batteries and pigtails that use a two-pin JST connector. This battery has a good picture of the polarity at the JST connector, and the barrel jack is center-positive. You can use it to adapt any of our barrel-jack wall warts to anything that has a JST power input. Sorry for the confusion, hope this helps!

  • I was thinking about adapting my EL wire so it would have a different connector. The JST are always so hard to unplug (especially when I had to replace the connector on the wire) and I'm afraid I'm gonna rip out the connector on my inverter. Have some questions that anyone could help me with... Do you think I should use barrel jacks, or something else? (I want it to be easy to unplug and not take up a lot of space. I'm using it on clothing) Should I snip off the JST on the EL wire and completely reterminate it, or just use adapters like this?

    • MikeGrusin / about 11 years ago / 1

      We feel your pain. You could reterminate everything, but before you do check out this tutorial which has tips on how to deal with stubborn JST connectors. I'll add my own tip that there are small nubs on the connector that you can take off with a hobby knife, that make them much easier to unplug.

  • Member #241366 / about 12 years ago / 1

    Seconding any confusion on polarity here – make sure you check which pole is which! I just fried one of my Electric Imp breakout boards.

    With, the red lead is + on this adapter, so if Vin is to the left of Gnd on the top side of the board (as it is on the Electric Imp board), you're gonna have to install the 2-pin plug-in JST socket on the underside of the board.

  • NicholasCLewis / about 13 years ago / 1

    To clarify does the Barrel jack center-pin connect to the same pin as the blue wire of this part:

  • ag3c / about 13 years ago / 1

    Which JST connector series is this? Looks like PH, but can someone from SparkFun confirm?

  • mli / about 14 years ago / 1

    which is pin#1 of the JST connector, center-pin of the barrel jack?
    Barrel jack center-pin = pin#1 of JST?

Customer Reviews

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0 of 1 found this helpful:

It's a cable, it's working out

I don't have much to say about this. It'd be hard to do too much wrong here. If you need to thread it through a small hole, the JST header can be removed by folding back the springs on the individual pins.