Linkwitz LM4780 PCB Proposal: Comments Wanted!

Well, I guess the proof is if it sounds good! I actually am having that one made in an olimex prototype board. I had some other stuff to made and needed to fill up a eurocard, and this one was the one I picked to throw in.

I guess we will see in a couple of weeks! 😀
 
This has some resistors and connections to be used as half an X-GC (SuperSymmetry) if any of it seems confusing. The halves og the chip are paralleled here, but splitting it to be discrete channels would be simple.

C
 

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digi01 said:
1,trying to isolated signal tracks and power supply tracks at different side,it can make all tracks short and clean.
Absolutely! The problems I was running into was one of getting thick enough power traces without overlapping signal lines. I'll have to play with that a little and see if I can get everything in from the same side!

[edit] Oh, and the dead copper was supposed to act as shielding. I read somewhere (and I have no idea if it was credible) that as much copper coating the board as possible added to signal rejection. That may only have been if it was grounded, so I will try and find out if I am mis-remembering![/edit]


Upupa Epops said:
David, isn't good to let all heavy devices ( PCB + elyts ) fit only by soldered pins of LM's... Remember also, that to PCB will be lead also heavy wires... Make there some fiting holes...
I completely agree about the devices being too heavy for just the chip pins. I can't believe I forgot to make mounting holes! As for the power, I was planning on using pinheaders and soldering power leads to those, but I think the direct wire method seems to have more suport, so from now on that will be what I will use for power.

Thanks for the suggestions!
 

njhifi

take a look at the National lm4780 stereo amplifier artwork .
Some pins are are NC(not connected ) but they are not connected internally and they are soldered on the board.
Do you have the boards to build the lm4780 pa03 amp?
 

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No doubt the data sheet is exactly as per what you have highlighted. Please check out the attached audiophile implementation of LM4780 and here the NC pins are connected. I wanted some info if there are any advantages in connecting these pins. As for the boards I have picked up a circuit from the net that supports 3 mode Stereo, Bridged and Parallel via few jumper settings using a 12 pin header. I am attaching the same. Have not ordered the PCB yet. For anyone interested in working on this design kindly note, I am not a professional PCB designer and hence mistakes are bound to be there and hence please do not use this design to build or order unless you are sure.
 

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