logic to intentionally short

I want an arduino to operate as a trigger for my smartphone camera. Wired selfie-sticks exist, and my research indicates that they are just TRRS connectors, and when you push the button it shorts the ring to ground. I want to get the button out of the equation, and do it via the arduino - but I need to do it at ms timing, so I don't think some sort of physical switch will likely work.

Is there a simple logic gate or chip that would achieve this, that I'm simply not thinking of?


A transistor as a switch perhaps? Have you measured the voltages on the relevant connections
of the TRRS ?

Depending on which standard the sleeve or one of the rings may be ground, more modern phone
are the latter I think (well for audio at least).

You won't necessarily get accurate timing if the camera does auto focus.

Transistor crossed my mind, but wasn't sure. And yes, it'll be a static camera so I'll manually set iso/focus etc.

It's a passive device w/ no battery, so it's whatever voltage is inherent to the output on the headphone jack of the phone.

BEAUTY. Your google-fu is better than mine. I specifically searched, and all I found was bluetooth options.