help with micro switch

blackcar · 05-20-2006, 08:49 PM

I have a IBM latop in a mini dock, docking station.
I though I could just wire up an extension into the on/Off switch on the docking station.
But when I opened it up the on/off button push against a rod that extend down to the main circuit board where there is a tiny switch.

anyways, I can solder, no problem, BUT the little switch has 5 leads coming out off it!?!?!

one side has 3 and the other side has 2.

anyone know why the switch would need 5 leads??
and switch 2 do I need to solder to turn it on??

thanks

blackcar · 05-20-2006, 09:17 PM

The top right pin has the word "SW1" near it, so I'm guessing that's one of them, still need to find the matching pin for that

turbocad6 · 05-20-2006, 09:19 PM

more than likely there is still only 2 that need momentary contact with each other
to start it..... picture?

turbocad6 · 05-20-2006, 09:21 PM

ahh, pictures...

just test the 4 corner ones.... pick one, then touch it with a jumper to one of the others..... continue until it starts..... those are them....

Rickertsen2 · 05-20-2006, 10:03 PM

Often times there are redundant leads on surface mount tact switches like the one in the picture. Looks at the traces on the PCB and see where they go. You will see that that there are only two different traces leading away from the switch. They usually have 4 leads. I have never seen one with 5. Maybie there are two common pins, a normally open and a normally closed.

BassBinDevil · 05-20-2006, 10:18 PM

Try measuring between the different leads with a voltmeter. If you find a voltage, keep the leads connected and push the button, and see if the voltage goes to zero when the button is pressed.

blackcar · 05-21-2006, 01:20 AM

Quote: Originally Posted by BassBinDevil

Try measuring between the different leads with a voltmeter. If you find a voltage, keep the leads connected and push the button, and see if the voltage goes to zero when the button is pressed.

Shouldn't voltage only go throught when the button is pressed??

finally found my volt meter
OK, I've found that when I have connectors on
the top left and bottom right pins AND the button is pushed I get connectivity.
(when the button is released, connectivity is broken)

On the other hand, without holding down the button
I only get connevtivity on the Top left and Top right pins
BUT there is NO change if the button is pushed......

Right now I'm guessing I should use the first scenerio, right?

turbocad6 · 05-21-2006, 01:59 AM

dude, it really is as simple as test jumping one by one to see which one fires it

blackcar · 05-21-2006, 02:02 AM

Quote: Originally Posted by turbocad6

dude, it really is as simple as test jumping one by one to see which one fires it

yeah, I just don't wanna fry the board (it's happened before in the past

)

I'll give that a try tomorrow, time for some sleep

W3bMa5t3r · 05-21-2006, 11:50 AM

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