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Is this just a matter of having the wrong search terms, or is there a reason why there are no SMD AC connectors. They all seem to be thru-hole, like this:

not what I'm looking for

I can imagine several benefits to an all SMD power supply board, such as eliminating spacers and mounting directly to a metal back plate (if one uses tented vias and perhaps a layer of kapton-like film between the board and plate), potentially leading to improved ruggedness, thermal performance (chassis as heatsink, backplate allowing for greater heatsink mounting forces), and compactness.

The only reason I can think of is mechanical strength, but that seems like a non-issue for most applications where the connector is firmly mounted to the chassis and there are no plugging forces transferred to the PCB.

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    \$\begingroup\$ I think I've seen pigtails from a panel mounted connector to a smd board connector. No directly board mounted smd connectors though. \$\endgroup\$
    – Passerby
    Commented Feb 11, 2016 at 21:31
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    \$\begingroup\$ If the connector's firmly mounted to the chassis and not firmly mounted to the PCB, then there's a risk of ripping the connections off the PCB with the slightest movement. \$\endgroup\$
    – Simon B
    Commented Feb 11, 2016 at 22:31
  • \$\begingroup\$ @SimonB I think the point is that the PCB is also firmly mounted to the chassis. \$\endgroup\$ Commented Feb 12, 2016 at 1:39
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    \$\begingroup\$ @immibis I'm not sure that would help. Any flexing of the chassis or inaccuracies in the mounting holes would rip the connector off the PCB. \$\endgroup\$
    – Simon B
    Commented Feb 12, 2016 at 19:50

2 Answers 2

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Most applications where an 'IEC' power connector like that is involved also use a whole bunch of through-hole components such as fuses, large capacitors, MOVs, large film capacitors, spark gaps, heat sinks, bridge rectifiers, large diodes, common mode chokes, surge reduction thermistors, large transformers, and so on, so an SMT version would not be of much benefit, and I think you've pointed out yourself the weakness of SMT parts, especially those with a load path to the outside world.

In fact I would say the through hole parts are relatively rare compared to wired chassis-mount parts. Below is one from this page, an X-box supply, and I think you can see what I mean:

enter image description here

There may be a few SMT parts on the bottom of that single-sided PCB, and there are certainly some on the small vertical green control board at the back, but there are an awful lot of bulky heavy parts that don't lend themselves to SMT.

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"Power" connectors do exist, but the IEC type seems to lend itself to through-hole applications. There are things that exist in other form factors though, such as this Wago terminal block part that is rated for 630V and 9A:

enter image description here

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    \$\begingroup\$ Why would you downvote this? It's just a different angle on the answer that hopefully brings a little more clarity. \$\endgroup\$
    – Daniel
    Commented Feb 12, 2016 at 17:20

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