Miniature 4PST toggle switch

Thread Starter

Novus

Joined Jul 1, 2021
11
Hi, I'm working on a product design which includes a toggle switch to trigger (latching) 4 different circuits simultaneously e.g. 4PST, however the design is constrained size wise to ideally 10 x 10 mm outer diameter (max 12 x 12 mm). So far I've only found significantly larger models.
Any suggestions/assistance would be most appreciated.
 

Irving

Joined Jan 30, 2016
2,322
Smallest I have is 23 X 13mm and Tbh I don't see you finding one smaller. Maybe a longer push on/push off?

What is it you are switching (current/voltage, ac/dc)? Do you have room for a subminiature 4p relay somewhere else?
 

Thread Starter

Novus

Joined Jul 1, 2021
11
The toggle switch controls on/off for 4 small video screens so low current/low voltage dc. There is plenty of room behind the front panel so a 4p relay could be a solution. Thanks.
 

Thread Starter

Novus

Joined Jul 1, 2021
11
Can you use a SPST switch and isolate the four inputs using diodes?
Diodes as far as I know will ensure current flows in one direction only. Not sure how this can work to keep the 4 circuits seperate with a SPST switch but definitly interested to understand if this could be a simple solution.
 

crutschow

Joined Mar 14, 2008
28,227
If you tell us the exact characteristics of the signal the switch controls, we could give more specific help.

Why do the signals need to be isolated?
 

Irving

Joined Jan 30, 2016
2,322
The toggle switch controls on/off for 4 small video screens so low current/low voltage dc. There is plenty of room behind the front panel so a 4p relay could be a solution. Thanks.
Is it the power or signal to the video screens that you're switching? If power, why can't they have a common switch supply?
 

Thread Starter

Novus

Joined Jul 1, 2021
11
If you tell us the exact characteristics of the signal the switch controls, we could give more specific help.

Why do the signals need to be isolated?

If you tell us the exact characteristics of the signal the switch controls, we could give more specific help.

Why do the signals need to be isolated?
For the design I purchased 4 x 4.3 inch video brochure modules with tactile buttons for volume up/down, on/off, start/stop fastforward and rewind. I initially tested combining on/off signal for 2 of the screens with one tactile button which seemed to work fine.
Next step I created a crude prototype combining the signals of the 4 displays.
Although initially the 4 screens turn on simultaneously and the videos start to play, sooner or later 1 or more of the screens either starts to ffw, rewind or volume goes up/down of its own.
 

Thread Starter

Novus

Joined Jul 1, 2021
11
i agree! Why do the signals need to be isolated? Could you describe what each signal is?
Since I'm in Europe I'm only reading yesterdays responses today.
See my answer to Crutschow were I try to explain the setup and result as best as I can.
The conclusion I reached is that the signals need to be isolated to avoid the undesirable random behaviour of the screens?
 

Thread Starter

Novus

Joined Jul 1, 2021
11
Is it the power or signal to the video screens that you're switching? If power, why can't they have a common switch supply?
As per above I believe these are signal switches? Since common switches do not seem to work I was thinking about 3 x 4PST Alps Alpine push button switches for pause/play, ffw and rewind and a miniature 4PST toggle switch for on/off.
PS the volume up/down buttons will be seperate for each screen.
 

Irving

Joined Jan 30, 2016
2,322
As per above I believe these are signal switches? Since common switches do not seem to work I was thinking about 3 x 4PST Alps Alpine push button switches for pause/play, ffw and rewind and a miniature 4PST toggle switch for on/off.
PS the volume up/down buttons will be seperate for each screen.
Ah, I get you... do you have a datasheet or link to the 'video brochure'?

The individual controls may need to be isolated, but this is could be better done electronically rather than using a multi-pole switch. The long wires to/from the video module could introduce noise and random actions. Can you be clearer about the setup in terms of relative locations of modules and panel, power wiring, etc.
 

Thread Starter

Novus

Joined Jul 1, 2021
11
Ah, I get you... do you have a datasheet or link to the 'video brochure'?

The individual controls may need to be isolated, but this is could be better done electronically rather than using a multi-pole switch. The long wires to/from the video module could introduce noise and random actions. Can you be clearer about the setup in terms of relative locations of modules and panel, power wiring, etc.
Ah, I get you... do you have a datasheet or link to the 'video brochure'?

The individual controls may need to be isolated, but this is could be better done electronically rather than using a multi-pole switch. The long wires to/from the video module could introduce noise and random actions. Can you be clearer about the setup in terms of relative locations of modules and panel, power wiring, etc.
I have added a picture of the video brochure module (these are pretty standard, I don't have a datasheet for the actual screens - and in fact received different displays than I ordered from the CN supplier)
I've also included a picture of the crude 'prototype' - the utmost right button would be the position for the 'on/off' toggle switch and the 3 buttons between the 3rd and 4th screen control rewind, pause/play and ffw (on top of the screens are the volume up and down buttons)
Each indivual video module on its own works perfectly with videos loaded via the micro USB ports.
So far I have not changed anything on the power supply, e.g. each display is powered individually by the battery that came with the screen/circuit board)
The longest wires (from the left side screen) does not exceed 25 cm - not sure if this could cause noise/random actions.
If you believe that in principle a multi-pole switch is not needed I could start with further testing combinations of 2 and 3 displays to see if I can get it to stabilize.
 

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Thread Starter

Novus

Joined Jul 1, 2021
11
Ah, I get you... do you have a datasheet or link to the 'video brochure'?

The individual controls may need to be isolated, but this is could be better done electronically rather than using a multi-pole switch. The long wires to/from the video module could introduce noise and random actions. Can you be clearer about the setup in terms of relative locations of modules and panel, power wiring, etc.
Not really sure what you mean with electronically isolating the individual controls? Can you maybe expand on how this can be achieved. Currently the (4) different wires are simply connected together to one of the pins of the buttons...
 

Irving

Joined Jan 30, 2016
2,322
So you connected the 4 red wires and 4 black wires of one function together onto one button?

In theory that should work... but theory & practice are odd bedfellows...

If the buttons are individual inputs to the on-board controller it'll work. But if they are scanned as a matrix, it won't...
 

Thread Starter

Novus

Joined Jul 1, 2021
11
So you connected the 4 red wires and 4 black wires of one function together onto one button?

In theory that should work... but theory & practice are odd bedfellows...

If the buttons are individual inputs to the on-board controller it'll work. But if they are scanned as a matrix, it won't...
Exactly - 4 red wires and 4 black wires per button.
Best results on uninterupted playing the 4 screens has so far been to switch the 'on/off' button followed by a prolonged push to the 'pauze/play button'
What made me wondering if this will ever work without seperating the circuits is that also the volume up and down controls start at random - which I guess are individual inputs on the controller board...
Since there may still be a chance for this to work without multi-pole switches (or maybe at least for some of the buttons) I'll start with further experimenting with combinations of 4PST and SPST with 2/3/4 screens.
Thanks again for your time and input so far.
I'll post back with the results.
 

Irving

Joined Jan 30, 2016
2,322
If you have a multimeter check resistances (power off) between black wires of different functions and between red wires of different functions on one board, also black to black of battery and to outer case of USB socket. I'm guessing/hoping all blacks are common while reds will have a resistance >10k to each other...

Also try, with power on, multimeter on voltage range, black probe on black wire, red on red - voltage around 3v, goes to zero when button pressed? Repeat with black probe on black of battery, red on red of switch - same result?
 
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Thread Starter

Novus

Joined Jul 1, 2021
11
If you have a multimeter check resistances (power off) between black wires of different functions and between red wires of different functions on one board, also black to black of battery and to outer case of USB socket. I'm guessing/hoping all blacks are common while reds will have a resistance >10k to each other...

Also try, with power on, multimeter on voltage range, black probe on black wire, red on red - voltage around 3v, goes to zero when button pressed? Repeat with black probe on black of battery, red on red of switch - same result?
I have a multimeter. Makes sense to check if all wires have the same consistency and are all acting as signal wires. Thanks for the detailed instructions. Great forum. Hoping to be of help to someone else sometime.
 

sagor

Joined Mar 10, 2019
512
I've seen small rotary 4pdt switches on devices like the old analog modems. All pins come out the back, and switch was only 10 to 12mm in diameter. Maybe look for those if still insisting on a physical switch.
 

Thread Starter

Novus

Joined Jul 1, 2021
11
Ideally - for esthetics - I would like to use a toggle switch for on/off.
If nothing else works and circuits need to be kept seperately - I 'll probably look for a relay solution as suggested.
If I decide not to use a toggle switch I could use the miniature Alps Alpine 4PST push button.
Thanks though for the suggestion.
Appreciated.
 

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