Hi,

Wondering if anybody has a lead or Digikey/Mouser/Vendor part number for a SPST tactile switch with a capacitive sensor?

ie: you can put your finger on the button and it can sense that and take one action, but when you physically PRESS the button, it will perform a different momentary switch function.

I've seen it done in the wild - but not sure where such a switch can be sourced!

 

This looks like what you want: https://connect.nissha.com/ime/en/tactile_switch/

 

That switch, the one shown in the link, may not be available in small quantities of less than a few thousand. There are touch sensor IC devices available, and it is possible that one could be combined with a regular button switch. The questions are: How much external circuitry are you willing to add, and how much are you willing to pay?
An alternative could be a metal-button switch insulated from it's mounting surface. That would take a bit of experimenting to make it work, but there are touch sensor circuits that are fairly reliable.

 

An alternative could be a metal-button switch insulated from it's mounting surface. That would take a bit of experimenting to make it work, but there are touch sensor circuits that are fairly reliable.

I seem to remember something along the same lines on a TV I had many years ago. It consisted of a metal ring and a metal dot in the middle insulated from each other. The touch of a finger, or should say the resistance of the flesh of the finger, would bridge the two conductors and with electronics determine whether a press has been indicated. You could do the same thing with the added tactile button below the metal button, so that a light touch would indicate one action and the press of the button would indicate another action. But yes, like Bill said, it may take more involved electronics for the sense feature. However, perhaps an N-Channel MOSFET would do. To keep it off you'd need a pull-down resistor and your finger would need to provide a pull-up voltage (LOW voltage) and actuate the circuit of some sort, which you didn't specify. It could be a relay, could be a solid state relay (SSR), or - again, some other circuitry like a "One-Shot" timer, whereas PUSHING the button down may cancel the timer. We could get more specific and accurate answers for you if we fully understood the intent.

 

I did come across the Nissha, and that along with the one I saw in the wild make me think such a thing exists - just not sure where it would be found as I'm not having much luck searching the Digikey/Mouser/Newark sites of the world. And yes, I'm definitely not looking for quantities in the 1000's.

Deployment would be much like I saw in the wild (it was on a broadcast console).

Once a finger touch was sensed on the button, there was a change registered to a screen next to the button that displayed what the button was currently configured to do. When the button was depressed, it performed that action. Allowed for contextual programming of the button function without requiring a specific label on or next to the button itself.

It looked like a plastic button, but perhaps its actually a glass cover to allow for that capacitive sensing. They had the same functionality with some rotary encoding knobs as well.

 

Haha! Found them!

https://www.wellbuying.com.tw/product/129

 

There are these: https://www.mouser.com/datasheet/2/295/ISC15ANP4-1663577.pdf $60 on Mouser. A different approach and maybe too costly but neat.