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edit approved Apr 30, 2015 at 9:45
Peter Mortensen
edit approved Apr 30, 2015 at 9:45
Peter Mortensen
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What are the 'knuckles' on thruthrough-hole LEDs and Photodiodesphotodiodes for?

I am using an IR LED and a photo diode, and I have designed the PCB according to the specsspecifications that I found on the datasheet - i.e. hole sizes for the pins being 0.6mm6 mm. However, on these components there are 'knuckles' (see below image) and these are wider than the hole size they quote for the pins.

enter image description hereEnter image description here

So the issue is the component doesn't go low enough into the board because of these knuckles.
  Why are they there? How can I know how wide they are in order to make my holes account for this?

What are the 'knuckles' on thru-hole LEDs and Photodiodes for?

I am using an IR LED and a photo diode, I have designed the PCB according to the specs that I found on the datasheet - i.e. hole sizes for the pins being 0.6mm. However, on these components there are 'knuckles' (see below image) and these are wider than the hole size they quote for the pins.

enter image description here

So the issue is the component doesn't go low enough into the board because of these knuckles.
  Why are they there? How can I know how wide they are in order to make my holes account for this?

What are the 'knuckles' on through-hole LEDs and photodiodes for?

I am using an IR LED and a photo diode, and I have designed the PCB according to the specifications that I found on the datasheet - i.e. hole sizes for the pins being 0.6 mm. However, on these components there are 'knuckles' (see below image) and these are wider than the hole size they quote for the pins.

Enter image description here

So the issue is the component doesn't go low enough into the board because of these knuckles. Why are they there? How can I know how wide they are in order to make my holes account for this?

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MrPhooky
MrPhooky
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What are the 'knuckles' on thru-hole LEDs and Photodiodes for?

I am using an IR LED and a photo diode, I have designed the PCB according to the specs that I found on the datasheet - i.e. hole sizes for the pins being 0.6mm. However, on these components there are 'knuckles' (see below image) and these are wider than the hole size they quote for the pins.

enter image description here

So the issue is the component doesn't go low enough into the board because of these knuckles.
Why are they there? How can I know how wide they are in order to make my holes account for this?