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Old 5th January 2014, 03:48 AM   #21
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Quote:
Originally Posted by Trileru View Post
If I route it it is ok, but I wanted it to go on the ground plane, and not clear the ground plane around it. That way it was easier and I had a hefty ground plane in that area. Even so I might route it to the nearest ground connection, and use that vertical area to separate the ground plane from the input side from the ground plane of the output side, and just use the lower connection to complete the circuit between both ground planes. As I read that is good practice as it keeps the noise out from the output area ground.
You mean like this?
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Old 5th January 2014, 03:53 AM   #22
Trileru is offline Trileru  Romania
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Yes, that's an older version and I had the ground plane on the bottom.
I attached a picture, I guess it will work like this? What you did is what I wanted, but with the ground plane on the top side. That heatsink that I used previously didn't have electrical connection. And had no problem with having the power plane on the bottom side. But this heatsink has also solder pads and it seems it clears the copper on it's footprint.
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Old 5th January 2014, 04:00 AM   #23
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If i may suggest something...rotate the rectifier diode so that their metal tabs are pointing outward in case they get hot under load and you decide to attach a heatsink (or a spacer) later.
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Old 5th January 2014, 04:03 AM   #24
Trileru is offline Trileru  Romania
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I will never draw more than 3A, and usually below 2A for sure. At 0.7V per diode at 2A that's 1.4W. I guess they are able to give off that heat with no heatsink attached? I'd rather not disturb the feng shui of the arrangement
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Old 5th January 2014, 04:08 AM   #25
Trileru is offline Trileru  Romania
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I don't get something. Before I've used SK129 and now I'm using SK129-PAD. Are they both heatsinks? Or is one a heatsink and the other is the pads for the first heatsink? In which case do I need to put them one on top of the other? Or do I install the pad on the back of the board? But how do I do that?
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Old 5th January 2014, 04:09 AM   #26
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Quote:
Originally Posted by Trileru View Post
I will never draw more than 3A, and usually below 2A for sure. At 0.7V per diode at 2A that's 1.4W. I guess they are able to give off that heat with no heatsink attached? I'd rather not disturb the feng shui of the arrangement
Good luck then and looking forward to see the finished board .
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Old 5th January 2014, 04:13 AM   #27
Trileru is offline Trileru  Romania
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Originally Posted by sghr220 View Post
Good luck then and looking forward to see the finished board .
Thank you!
Hope I finish it in a way that I'm satisfied. Also I want to have some options on it like snubber etc so I make some measurements of my own.
I attached a picture. With the pads installed, if I connect them to ground I can see that the trace is not removed from it's center, like it does not have holes there.

edit:
nah, ignore this message, all of the holes are like that. I wasn't sure that pads have holes actually but I guess they must have.
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Last edited by Trileru; 5th January 2014 at 04:15 AM.
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Old 5th January 2014, 04:21 AM   #28
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Quote:
Originally Posted by Trileru View Post
I don't get something. Before I've used SK129 and now I'm using SK129-PAD. Are they both heatsinks? Or is one a heatsink and the other is the pads for the first heatsink? In which case do I need to put them one on top of the other? Or do I install the pad on the back of the board? But how do I do that?
Both are heatsinks the first one without the soldering pads and the other with the pads. Your top layer where the regulator and its heatsink resides is the layer with the ground plane am i right?

If i am right how are u gonna solder the heatsink legs (through hole) to the top layer with no clearance between its body and the board?

I don't know about u but i am sleep deprived at the moment so may be i am not seeing things right.
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Old 5th January 2014, 04:25 AM   #29
Trileru is offline Trileru  Romania
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The top red layer is the ground plane yes.
Well, the heatsink has two pins, and I guess the solder pads are on both sides right? I'm thinking of soldering them on the bottom side, I can't solder them on top as the heatsink would cover those. I really don't know how to make sure that the pads are on the bottom or/and on the bottom. The holes of the heatsink has pads, that are electrically connected on both sides so why would that be a problem?

edit:

I will have to isolate the regulator from the heatsink, that's for sure.
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Old 5th January 2014, 04:31 AM   #30
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Originally Posted by Trileru View Post
The top red layer is the ground plane yes.
Well, the heatsink has two pins, and I guess the solder pads are on both sides right?
Nope...the solder pads are on one side only...that's the side opposite to which the actual component are...unless you installed the heatsink on both layers.
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