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IC placement on PCB design

IC placement on PCB design

IC placement on PCB design

(OP)
I am designing a PCB, and I have to find a decent placement for one of the ICs, unfortunately I am running out of space, and it cannot be made any larger.

I can however mount the IC on the bottom copper layer. I use this layer as a ground layer currently. I just wanted to know if this is acceptable to do, and if it's acceptable to be soldering the pads on the top copper layer.

I don't see any reason why not...but I design these as a hobby, and have no formal education. and would like some advice before I send this off to be printed. Thank you all in advance ^_^.

RE: IC placement on PCB design

Hobbyist stuff is not allowed here so expect this to disappear soon.

If you are talking thru-hole parts you can not have the boards assembled in the normal manner if you put parts on the bottom.
But Yes you can do it if You solder it.


If you use surface mount parts, they can be done on both sides and are regularly.  It does increase assembly costs about 60% over all the parts on one side.

Keith Cress
kcress - http://www.flaminsystems.com

RE: IC placement on PCB design

(OP)
I apologize then for posting, most forums aren't restricted in such a manner. thank you for your fast response, you answered my question, and you deserve karma for doing it when technically you aren't supposed to be helping me. Thanks

RE: IC placement on PCB design

Quote:

It does increase assembly costs about 60% over all the parts on one side.

This really seems like an exorbitant increase, but it does.  
itsmoked, I ran into this with the board vendors that I got quotes from on the project you and I worked on.  This was after they even admitted that the only impact on them as a manufacturer is that that they need to have someone get the bin of boards from one end of the line and re-insert it in the machine again and that it amounts to about 3 minutes of labor.

Of course there is the setup charge to program the machine for the extra process.  That is why I always want that quoted as a one time NRE, not amortized into an order.

Another rule of thumb I have found to be true regarding board quotes: figure out how much you figure the board should cost for parts and raw board.  Then multiply by 160%.  That typically gets in right in the ball park of what you can expect.


  

RE: IC placement on PCB design

Thanks neoaikon.  Good luck with that.


Noway. Greetings.

Thanks for that number.  I've never actually thought about it - just been horrified by any number given.

You make it back home yet?

Keith Cress
kcress - http://www.flaminsystems.com

RE: IC placement on PCB design

Greetings and Salutations,

No I haven't made it home yet. I keep trying. I recently applied for yet another position and got yet another dear john response.

The 1.6x comes from a former boss who said that experience showed it to be pretty accurate.

 

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