Shining an LED backwards through a PCB via ?

[Boo2]

Hi,

As per the title : I was considering using a PCB as the faceplate for a project and would like to mount an SMD LED on the other side from the face the user sees so that the LED shines outwards towards the user through a hole mounted directly beneath it and between its mounting pads. LED type needs to be high efficiency indication type, not massively powerful Cree etc.

Anyone done this ? Is this a standard thing that is done and there exists a whole variety of parts designed specifically for this application </hopeful>, if so what do I search for ?

This is my first post here, so hello to all from Brighton, England.

Boo

 

[ronsimpson]

Surface mount or through hole?
I think there are many like this that could be mounted through the PCB. The clear part will inter the PCB and the legs will hang up on the board and be soldered down.

 

[gophert]

Hi,

As per the title : I was considering using a PCB as the faceplate for a project and would like to mount an SMD LED on the other side from the face the user sees so that the LED shines outwards towards the user through a hole mounted directly beneath it and between its mounting pads. LED type needs to be high efficiency indication type, not massively powerful Cree etc.

Anyone done this ? Is this a standard thing that is done and there exists a whole variety of parts designed specifically for this application </hopeful>, if so what do I search for ?

This is my first post here, so hello to all from Brighton, England.

Boo

It is not commonly done. You probably want a route red hole or drilled hole in the PCB, not a tiny via hole. Usually you can simply add additional board outlines within the main outline of your board to subtract areas (route red or drilled voids).

usually SMD parts as ronsimpson showed fire light straight up, there are less common but widely available "side fire" LEDs that emit light at 90-degrees (along the plane of the board). There are some that fire down - called surface mount, bottom entry. Ron's is one example, there are others that don't need the depth of the board but are simple bricks with the anode and cathode covering the entire end, they can be mounted to fire up, side or down but will not have to be in the plane of the board.

 

[ronsimpson]

Some of the surface mount LEDs are so small they might mount on the PCB like they should but bottom side. I am looking at one that has a height of 1.1mm. Found another one 0.8mm.

Bottom entry: Now that I see how to look for them Digikey.com has 200 different types. This is what I used years ago.

CSM28R2CZ

 

[Visitor]

They are also called reverse mount.

 

[ronsimpson]

They are also called reverse mount.

That is the problem, each vendor has a different set of words and we don't know what they are.