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Can you help me identify the 5 pins on this 2.5mm stereo jack connector? Answered

I've looked at a few data sheets for different stereo jack connectors, but none of them appear to identify what these five pins would do in a common application. I'm building an audio amplifier, and this is the connector (de-soldered off another circuit board), and I have no part number. Please see the attached picture. Thanks for any help you can offer.


You usually get tip,ring and collar for the stereo jack, and at least one other connection which is switched. By far the easiest way to find out what you have is to measure continuity to the pins.

So it looks like the middle is the ground, and the two outside pins are for the channels (as best I can tell). The far right according to the picture is about 0.47mA when plugged into my computer headphone jack and the far left is 0.07mA. The only problem is that my amp is only going to be one channel. Hooking up either pin to the Vs from the amp, as well as the ground, is giving me no sound. Any thoughts? Thanks!

Yes, don't connect anything in the input to the supply ! Connect the collar to ground, but the tip and ring go to the input. Add a 2K resistor in series with tip and ring to the input and make a very crude mixer.


If you're going to provide mono output, signal should go to the tip connection and signal ground should go to the sleeve connection; that's standard usage for this sort of connector.

If you're getting "no sound", trace the connections all the way through. The output may not be strong enough to drive whatever you're plugging into this, or you may have a wiring problem.

If you haven't solved your issue yet, try this. To identify which pins have audio connect an IPOD or MP3 player to the connector with a stereo cable, then find cheap computer speakers with a built in amplifier, cut the end connector from speakers and expose the copper wire. while your IPOD or MP3 is plugged in and playing, start touching the pins with exposed wires to find out which pins have audio, don't worry if you cross connect the wires they won't short out the speakers, the voltage and amps are minimal to blow anything up......good luck trying it....

Usually, that would be tip, ring, sleeve, tip bypass (connected to the tip wire only when a plug is not inserted) and ring bypass (ditto). Those bypass connections let you have the signal normally go to internal speakers but have those cut out automatically when the headphones are plugged in.

As far as which connection is which: As Steve said, experiment.