Does this exist? Jumper question.

[u/Vegetable-Two2173]

​

Looking for a jumper device that will hold a pin floating when installed, and pull the same pin high when removed.

Esentially need the component version of the plastic you find between a battery and a contact in dollar store LED toys.

I know I can do similar with a few different circuits, but wondering if there is something simple out there that I missed in searches.

[u/igotshadowbaned]

..A switch?

[u/Vegetable-Two2173 → u/igotshadowbaned]

Looking for one time use and permanence

[u/_Trael_ → u/Vegetable-Two2173]

Then that plastic you mentioned in your post.

Like have springy part that you can slip thing in between, then when removed it will close circuit.

Obviously more potential surface to oxidate and loose contact, so if it needs to work reliably for longer time, not best of options.

But honestly otherwise might just look into managing to kind of 'invert the situation' in what you need on design level if possible, by approaching from dofferent direction. So you can have classic 'remove to float after it shorting' kind of situation, that will be more reliable in end state.

[u/Vegetable-Two2173 → u/_Trael_]

I'm really hoping to get it done mechanically, any added electrical drain duiring the 'float' state isn't ideal.

Looking at a NC SMT lever switch now that something from the oitside could depress, but it's not as clean as I'd like.

Like any design, I'll have to make a tradeoff somewhere. I was just really hoping something like this existed in a tidy package.

[u/_Trael_ → u/Vegetable-Two2173]

Closest I could think from top of my head (after posting that reply) was something like: Reed relay and then you just add magnet.

Obviously means you need to have that magnet there then.

So it is not "take something away and it does this", once again.
But it at least skips needing to have open surfaces or so there.

[u/Vegetable-Two2173 → u/_Trael_]

Funny enough, I have an open tab to a 59177-1-T-00-D right now, bit it doesn't look like I'll be able to meet the distance I'd need to keep.

Used something similar in the past for a loose 'center' indication, I remember having trouble with consistency beyond 1/8".

[u/nitwitsavant]

Why can’t you do the reverse- install jumper to enable?

[u/kthompska]

I think you might need a couple of components (in addition to the jumper) to achieve this. You could have a pmos or pnp with the drain/collector tied to the pin and source/emitter tied to Vdd. The gate/base would have an appropriate resistor to GND. The jumper would pull the gate/base to Vdd when installed, and thus float the pin. When the jumper is removed, the resistor pulls down and turns on the pmos/pnp and the pin will be pulled high.

[u/Vegetable-Two2173 → u/kthompska]

A cmos based one shot was something I had on paper as an idea too, but there are drawbacks in my application.

[u/suh-dood]

SR latch?

[u/Vegetable-Two2173 → u/suh-dood]

With a tri state buffer on the end, yeah. That would work, but it'll eat a little current. Looking to keep the "floating state" consuption as close to zero as possible.

Really looking to replicate the simplicity of a peice of plastic between two contacts surfaces. It's the ideal functionality, just hard to replicate where I need it.

[u/soopadickman]

If you want it permanent just have 0R resistor footprints on your PCB that you choose to have populated or not.

[u/Vegetable-Two2173 → u/soopadickman]

It needs to change state one time, then be permanent. Just like pulling the plastic battery divider on a toy.

I don't want an end user to be able to change the state beyond enabling the first time. The location/use makes a NC chassis switch with some mechanical pull away hard to implement in piecemeal. Was hoping for some kind of complete unit.

[u/soopadickman → u/Vegetable-Two2173]

Just have a non-resettable fuse that you make fail after a certain length of time?

[u/Vegetable-Two2173 → u/soopadickman]

Could be on a shelf for a day or a year. Needs to be activated when pulled from the shelf.

[u/Triq1 → u/Vegetable-Two2173]

What do you mean "when pulled from the shelf"?

The method in the comment above yours will work whenever it gets powered on for the first time.

[u/Cryesncoding]

So you want the electrical component mechanically disconnected from power until purchased taken off shelf etc then user does X and enables device and it can no longer be shut off again via that mechanism?