Lm4780 SS PCB

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So, at the risk of asking a question that been asked tons of times and on an old thread to boot: what can I do with the Eagle files? Does the free version of Eagle allow you to import them and modify? Does it allow you make the Gerber files with it? Can you import Eagle into some of the other free PCB software?
 
If you are interested in the "ready to etch" pdf's I can upload those for you. It is a basic application of the LM4780 but it seems to work well. Pinkmouse, what is your exoerience with the zobel resistor and cap? I have not used it since I did not have the parts. If you can convince me to use them, I will purchase the parts :)
 
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I used to live next door to the Crystal Palace TV transmitter, and had a few problems with noise getting back up the speaker lines with the NS chips, the Zobel sorted it, and I've since been putting it in by habit. You might not need it, but it doesn't hurt. Your call. ;)
 
My LM4780

I tried pinkmouse pcb and it works . The Amp is super silent and yes , i used the component values from audiosector .Thanks to pinkmouse and Peter .
 

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Hello from Serbia :)

I want to build this revision of chip amp. Special tnx to pinkmouse for nice revision of PCB. I want to build Stereo Amp so here I am :)

I mark all components to the sch file so if someone who build can tell me are this is ok?

An externally hosted image should be here but it was not working when we last tested it.


One more question, why are PGND1, PGND2 separated from GND, SG1, SG2, CHGND, OG1 and OG2 ?

Thanks for all.
 
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One more question, why are PGND1, PGND2 separated from GND, SG1, SG2, CHGND, OG1 and OG2 ?.

Hi Tesla. That's just a workaround to aid laying out a star ground, if you look at the pcb you can see what I mean. As for component values, they are all on the datasheet, the standard stereo layout. You may have to recalculate the soft start values for your voltage rails, but that data is given in the datasheet as well.
 
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Oops, it looks like the datasheet has been revised since I did this layout. I'll try and find an old copy that I worked from, that should clarify matters.

edit: Right, I can't find an old copy of the datasheet, but as my work was based on that of Brian and Peter, you can use the schematic from the Audiosector website for component values.
 
blueskynis tnx for fast replay ;)

All this values of components I take from here:

http://www.unisonus.com/pl/p/file/c6f87e7d34faa18ced6d26ca51eefc12/LM4780_PCB_sch.pdf

I download data sheet, witch schematic i shoud watch...All schematic are difrent than pinkmouse version. I see that mute function is using like soft start the values are 8K2 and 15K resistors and 10uF. What else is wrong?

Hi,

  • Rz1 and Rz2 should be 2R7 ohms, not 22k
  • R1 and R2 should be 22k, not 2R7 ohms.

@pinkmouse

I was commeting on his schematic not yours. Your schematic is in accordance with the datasheet.
 
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