Author Topic: What is purpose of V-shaped cutout in LED's pad?  (Read 1089 times)

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Offline ocset

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What is purpose of V-shaped cutout in LED's pad?
« on: November 08, 2017, 06:19:18 am »
Hello,
What's the purpose of the V-shaped cut-out in this LED's pad? (Z8Y19 LED) Is it to help it sit centrally on the pads when its being reflow soldered?

The footprint is seen on page 21 of the datasheet

Seoul Semi Wicop Z8 Y19 LED:
http://acrich.tw/_upload/Goods_Spec/Specification_Z8Y19_Rev5.2.pdf


We have 200 PCBs where we forgot to put the V-shape in...must we throw them in the bin?
The ones we tested work well and the LEDs look perfectly central, even though we forgot the V-shape.
 

Offline trophosphere

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Re: What is purpose of V-shaped cutout in LED's pad?
« Reply #1 on: November 08, 2017, 06:35:21 am »
I would think it is more to help denote which pad is the cathode.
 
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Offline T3sl4co1l

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Re: What is purpose of V-shaped cutout in LED's pad?
« Reply #2 on: November 08, 2017, 06:35:29 am »
Probably just for polarity (assuming you don't have space to do so on silk).  Outside chance it reflects the part metallization, but yeah, it isn't going to matter, not at this scale anyway.

Also if it were intended, there would be dimensions.

Tim
Seven Transistor Labs, LLC
Electronic design, from concept to prototype.
Bringing a project to life?  Send me a message!
 
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Offline maukka

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Re: What is purpose of V-shaped cutout in LED's pad?
« Reply #3 on: November 08, 2017, 07:54:11 am »
No need to include the cathode indicator on the board.
 
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