Can't find 7-8.4V DC 1Amp on/off switch

Using Arduino General Electronics
#1

I'm using a 2S Li-ion battery to power three motors. The battery has about 8.4V fully charged and the motors and electronics draw about 1A of power. I already spent hours looking for a small switch that can be used as the main switch for this set-up. Space is very scares so the more compact the switch is the better (best would be 15mmx8mmx10mm or smaller). I already spent hours looking for such a switch with no success. Am I just looking in the wrong places or does it not exist? (the ones that I found are rated for much higher amperage and therefore are pretty big).
Any help is appreciated.

Looking for:

  • 7-8.4V DC 1Amp on/off switch
  • rocker, slide or similar type
  • the smaller the better
#2

You don’t need to look for a switch rated at such a low voltage, they don’t exist. That is the guaranteed cut-off voltage at the switch’s rated current, so as long as the switch is rated for at least 2 to 3x the maximum circuit voltage, you are good. It doesn’t take much distance to cut off 50V, so I think you’ll have a hard time finding a switch rated for much lower voltage than that.

And for a 1A draw, you want a switch rated at least 3x that, but - motors draw a lot more current on startup and stall, the switch should be rated for 2 to 3 times that amperage.

Define small.

#3

Thanks for the reply.
15mm x 8mm x 10mm or similar would be ideal. Most switches that I could find that where rated for 12VDC to 125VDC had very low amp ratings.

#4

That is tiny. Perhaps a lower rated switch that starts the Arduino, then a separate MOSFET that turns on power to the motors independent of the switch?

#5

Search for "ultra small microswitch" or "tiny microswitch" and you may be surprised by what you find.
These seem to fit your size and current specs: http://pewa.panasonic.com/components/switches/micro-switches/ah1/

#6

If not for the space constraints, i'd use a circuit to do the power switching and let low current pass through the button.

#7

Thanks for all your replies. The Panasonic on/off switches (rocker switches) are a little to big (25mm long), so I’m still looking for a switch.
Using a circuit to do power switching might actually work because the form factor will be very different from a traditional switch.

Are there any off the shelf circuits for power switching? What would such a circuit be called?

#8