DT3T (On-On-On) Switch - Looking for Symbol and Footprints

I am looking for a 3 position switch x2 symbol and footprint for Kicad. I know someone has made this before and I am hoping to reuse that work.

Can anyone point me to a library that has this symbol?

Thanks

We need to know the switch. Can you provide a link to the data sheet?

I am open to other components, as long as they fulfil the 3 position (On-Off-On) Double Pole requirement.

Here is the type of switch I had in mind: https://www.amazon.nl/gp/product/B08KZW2L9S/ref=ox_sc_act_title_1?smid=A327GUZ5FBQX9V&psc=1

switch

The ā€˜3 positionā€™ is not really too relevant. The only difference would be the symbol could possible be drawn in an off position. There is not enough information on the part there for a footprint but it should be easy enough to make your own. It is an essential skill so check the FAQ. Iā€™m pretty sure there is a tutorial in there for this. Without an actual datasheet you may have to buy the part and measure it. No pin width is given and the distance between pins looks like it is ā€˜outside to outsideā€™ which is probably wrong. Chances are that is a ā€˜centerā€™. Still, pin width is missing.

Note ā€œUnit Aā€. There is also a ā€œUnit Bā€. I know from experience that you can end up spending more time looking for a symbol/footprint than it would take to learn to do it. :wink:

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Fully agree with:

(and some *&^%$#@! to get over this 20 character *&^%$#@!)

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The 3 positions actually all need to provide a signal path. Here is the schematic I am working off of. Notice that is is a dual-gang (two pole) 3 position switch.

I found the symbol in the KiCad library. Now I am looking for an actual component and footprint.

I canā€™t find any of these types of switches so far looking at DIgikey. Anyone have any component suggestions?

Once I have a component picked out, I can then proceed with creating the footprint. But just finding the component is proving difficult.

dual-switch

This description is not of an ā€œOn-Off-Onā€ switch which would be a nPDT switch with a center off position. This description would be a nP3T switch and could be described as an ā€œOn-On-Onā€ switch. The DP3T switch in the schematic has 8 pins (they are numbered), and the picture of the switch that you provided above only has 6 pins making it a DPDT switch.

So, what exactly are you looking for? DPDT with a center off position, or DP3T?

Usually best to check what designs are available (and, actually in stock) before basing a design around something that isnā€™t actually made or wonā€™t be available for n months.
Both Mouser and Digikey offer parametric searching - would suggest that you trawl through their offerings to see if anything matches.
The image that you link would normally be chassis mounted and connected by flying leads or an on board connector, so you can represent it in the schematic as a switch and on the board by a connector or series of solder pads.

DPDT/On-Off-On is the switch photo you posted.

I use SPDT/On-Off-On and your Schematic looks like this is what you want (looks like youā€™re not using the other two On posts (but difficult to see clearily). If SPDT will work for you, a Step model and .MOD file are attachedā€¦

SW_Toggle_Blue_wSlots.kicad_mod (2.9 KB)
Toggle_SW_Blue_R0.step (260.7 KB)


Screen Shot 2020-11-02 at 7.57.25 AM

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My mistake with the above component. I have now found the actual component I want.

I need a DP3T On-On-On switch.

Component: https://www.digikey.com/en/products/detail/nkk-switches/M2044SS1W03/1027467
Datasheet: https://www.nkkswitches.com/pdf/MtogglesBushing.pdf

The symbol is already available in KiCad. It is just the footprint I need. I understand it is possible to create it, but I figure somebody has used this component before.

This is a strange one because the schematic symbol has 8 pins but the footprint has 12 pins. Is that possible to accommodate using the existing symbol?

Their 3D models are available - click the link to them (on the page you posted). Select your preferred ā€˜typeā€™ (suggest the STEP model). I looked at it and it should be ok for you to make a footprint with.

Basically, start a new Footrprint, add Pads (or use the S-DIP pad and select quantity/pitchā€¦). Then, add the STEP fileā€¦ some homework on How to do this is your taskā€¦

I think the switches youā€™re looking for are best covered by the APEM 5000 series toggle switches, which is one of the widest offerings I know of:


As youā€™ve noticed yourself, the ON-ON-ON function needs more pins, and the layout is not trivial.

No affiliation, but Iā€™ve used them myself.

EDIT: Huh? a simple URL converts to a blurb? Never seen that before. I learn something every day.

Yeah, their nP3T switches are odd. There are 12 pins and you will need to provide traces on the board connecting two pairs of pins. See this screenshot from the datasheet that Iā€™ve annotated for you:

As shown, you will want to connect pin 3 to pin 5 and pin 9 to pin 11 external to the switch with traces on the board. In use it will be:

           |      switch A       |      switch B        |
-----------+---------------------+----------------------+
(3) Up     | 2(pole) to 1(throw) | 8(pole) to 7(throw)  |
(2) Center | 2(pole) to 4(throw) | 8(pole) to 10(throw) |
(1) Down   | 2(pole) to 6(throw) | 8(pole) to 12(throw) |
-----------+---------------------+----------------------+

I would probably draw this symbol as a 3 or 4 unit symbol. Units A and B will be the actual functioning switch based on the above table, and Unit C (and Unit D if going for a 4 Unit symbol) will be the pins that need to be shorted together for proper operation. Then I can stick Unit C (and D if used) in a corner of the schematic with wires connecting the proper pins and a text note explaining what it is and keep that functionally necessary clutter out of my schematic logic.

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