Parts: Tactile switches for your next project

Electronics parts can be a pain to choose. It’s often hard to tell from manufacturers’ datasheets if a part will fit your design. We auditioned six different tactile switches to find a cheap button to use in upcoming projects. A tactile switch, also called a momentary button or push-to-make switch, is commonly used for input and microcontroller resets. This type of button creates a temporary electrical connection when pressed.

Footprints for most of these buttons are available in the Cadsoft Eagle library switch-tac, or in the Sparkfun parts library under TAC_SWITCH. Buttons in the image above are discussed from left to right.

Through hole push button switch (6mm): This switch will appeal to fans of through-hole parts, but you can see that it’s actually smaller than the 6x6mm surface mount buttons. Note that it does not have the standard 0.1″ straight mounting legs, and thus won’t fit in a breadboard. Common package name(s): DTS-3 (S1 above).

642-MJTP1250 (16 cents)

Regular SMD tactile switches (6 X 6mm): A 6 x 6mm tactile switch is probably the most common surface mount button. Even though it’s surface mount, it’s large and easy to solder.  The button has two pairs of leads (1&2, 3&4) that connect internally to the same switch — although there are four legs you only get a single switch. You only need to connect one pin from each pair to use the button, but it makes no difference if you decide to connect both. The yellow and red buttons are rated in terms of the force required for activation (gf), yellow requires the most force (520gf) and makes the loudest snap. Common package name(s): DTS-6 (S2 above).

101-0164-EV (22 cents)

101-TS5922T5202-EV 520gf YELLOW (36 cents)

101-TS6824T2604-EV 260gf RED SMT (51 cents)

Small SMD tactile switches (4.5×4.5×0.4mm): Unlike the previous buttons, these tiny switches require practice and skill to solder. While the mounting area is only 12% smaller than the previous buttons, the leads are tiny and hidden under the package. Like the 6 x 6mm tactile switches, these are rated in terms of actuation force (gf). We were unable to find a ready-made footprint for this part.

688-SKRMAA 160gf (30 cents)

688-SKRMAB 260gf (30 cents)

Comments

  1. Satiagraha says:

    That’s a pretty nice summary of SPST cheap switches, now how about Cheap Toggle Switches?

  2. Brickmodder says:

    I’ve been using C&K KMR2 tact switches on my boards that
    require tact switches for a few months now. They are approx
    4.2×2.8×1.9mm and the exposed SMT pads can be hand soldered.
    link: http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=401-1426-1-ND

  3. Ian Lesnet says:

    That’s a great tact switch, thanks for the link.

  4. Tod E. Kurt says:

    This is a great article. I love seeing these kinds
    of comparative analysis of electronic components.
    The inclusion of the Mouser/Digikey links and pricing
    estimates are very welcome. There are thousands of parts
    out there and it can be overwhelming figuring out which
    one to choose.

  5. beastmaster says:

    learn how to use that momentary switch to power on your gadgets…

    http://www.beastmasterelectronics.com/wordpress/2008/09/control-dc-power-via-a-momentary-push-button/

  6. Simon says:

    If there is not much room available try these
    (3mm x 2.5mm + exposed smd pads, also available side
    actuated):
    http://www.omron.com/ecb/products/sw/2/b3u.html

    Bye,
    Simon

  7. psurf says:

    Dealextreme has a collection of electronic switches:

    http://www.dealextreme.com/details.dx/sku.5588~r.39889807

  8. mem.namefix says:

    http://www.futurlec.com/

    cheaper than any of the other sites posted.

  9. ThankfulOne says:

    you probably just saved me quite a few ‘tries’ thanks

  10. AudioRichter says:

    Thank you!!! I am learning to hack/mod the buttons on my wii mote and this was lovely! Woot! Music controller ahead!

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