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Bottom-firing surface mount LED?

Big question mark -- is this even a sensible thing to ask for? I'm designing a board at the moment, and the _only_ components that would need to go on the back side are a pair of LEDs (the board is mounted with it's back to the instrument's front panel).

If someone made something like a surface-mount LED that shined on it's bottom, then I could make a hole and put the LED over it, and only have to do fabrication from the top.

I think I've answered my own question. This is absurd. I'm going to post this for your amusement, and for the off chance that this is really made. Otherwise, I'll just have a board with two (and only two) components on the backside.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

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Reply to
Tim Wescott
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Lumex

Cheers

Reply to
Martin Riddle

Yeah, they make trimpots like that.

You can get LEDs that are lensed bumps with flat leads sticking out the sides. Maybe mount them upside down?

John

Reply to
John Larkin

AFAIK these are pretty standard. If you browse through your favourite parts supplier catalogue you should find some. I've also seen these in desktop telephone sets.

--
Failure does not prove something is impossible, failure simply
indicates you are not using the right tools...
nico@nctdevpuntnl (punt=.)
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Reply to
Nico Coesel

I know of LEDs made for rear-surface-mounting, with firing forwards through PCB holes roughly 10 mm in diameter.

These LEDs that I have in mind, would be Cecol / Citizen ones of CL-654 series. These are 16-lead SMT packages with 8 LED "chips" / "dice" that are individually accessible, as in able to connect in series or in parallel (rated for usual P-noted CL-65* devices). If parallel of the 8 chips is noted as OK, then 2*4 or 4*2 series-parallel shouild also be OK.

Without overt statement such as from LED datasheet that paralleling LEDs or individual chips of multuichip LEDs is OK, don't bet your house that paralleling LEDs is O)K.

--
 - Don Klipstein (don@misty.com)
Reply to
Don Klipstein

Nothing wrong with making the hole just big enough for the body, so that the LED drops into the hole...

Reply to
Robert Baer

to

y
o

until you need to assemble it with a machine, if you look at this datasheet:

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you can see the type that it meant to go through the pcb and be soldered on top is also bottom up on the tape, if it wasn't the pick-n-place machine would have to flip it

-Lasse

Reply to
langwadt

Check out Avago HSME-C265 and the whole HSM*-C265 series.

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Mikko OH2HVJ
Reply to
Mikko OH2HVJ

Sure. We use them where there is a carbon-pill switch contact on the opposite side. No one figured out that LEDs are small enough to fit under the keypad, so mounted the LEDs on the opposite side, blocking wiring channels on both sides. I'm in the process of doing it right (gotta fit ten more pounds on the card). ;-)

Sure.

No, it's a normal thing. On DigiKey's product search, look for "Mounting Type" of "Surface Mount, Bottom Entry" or "Surface Mount, Lens Through Board".

Reply to
krw

OSRAM TopLED RG style. I just bought a bunch of these.

Example DigiKey part #: 475-2777-1

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_____________________
Mr.CRC
crobcBOGUS@REMOVETHISsbcglobal.net
SuSE 10.3 Linux 2.6.22.17
Reply to
Mr.CRC

A bit late, but you may try:

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Should be available on DigiKey

Reply to
Sam

http://www.electr> > tim wrote:

Those Kingbright LEDs with Z-bend leads are of such dimensions that they project down into the hole of the PC board. If typical 62.5 mil thick boards are used these LEDs are just shy of coming through the board. That makes them perfect for applications where the back side of the board wants to be covered with etched push button switch contact fingers and then overlaid with a laminated plastic over click dome switches or silicon molded keypad. A window under the LED opening makes a very nice indicator positioned near the push switches.

Nice Indeed.

--

Michael Karas 
Carousel Design Solutions 
http://www.carousel-design.com
Reply to
Michael Karas

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