here is a good layout for the lm3886 pa 100 watt ref schematic an-1192. has the following features. mute/ snubber network on output/ signal ground to power ground resistor. the 68 uf caps can be 22 uf to 68 depending on the high freq. rolloff you want.
for my application i am usig 22 uf. also the 1 uf on the input can be 1uf to 10 uf as this is used for decoupling the input as well as dc blocking. larger values will allow more bass to the input smaller more treble. amp is dead quiet, no noise a v +- 40 volts using my pwr supply listed elsewhere. the output resistors are .1 ohm 5 watt 1% silicon coated pwr resistors mouser# 588-45fr10e and they stand upright on the board. all others are 1/2 watt 1%metal film. the 20 k feedback resistors were matched with a meter so buy 20 pieces unless you go to .1 % for equill gain per chip.
for my application i am usig 22 uf. also the 1 uf on the input can be 1uf to 10 uf as this is used for decoupling the input as well as dc blocking. larger values will allow more bass to the input smaller more treble. amp is dead quiet, no noise a v +- 40 volts using my pwr supply listed elsewhere. the output resistors are .1 ohm 5 watt 1% silicon coated pwr resistors mouser# 588-45fr10e and they stand upright on the board. all others are 1/2 watt 1%metal film. the 20 k feedback resistors were matched with a meter so buy 20 pieces unless you go to .1 % for equill gain per chip.
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Humm... I think the circuits are too tiny, don't forget that is a high power device. These tracks will not suport deliver 100W RMS of continuous power.
Common Ground is good to do, you can avoid some problems with this!
Check out my BPA200 Design. Not finishied yet, but you can follow the idea !
http://www.diyaudio.com/forums/showthread.php?s=&threadid=79990
Common Ground is good to do, you can avoid some problems with this!
Check out my BPA200 Design. Not finishied yet, but you can follow the idea !
http://www.diyaudio.com/forums/showthread.php?s=&threadid=79990
TRACE SIZE
I ALSO LAY A BIG BUILD UP OF SOLDER ON THE LOAD CARRYING TRACES TO HANDLE THE CURRENT WORKS FINE THIS IS DONE ALOT IN MACHINERY PCB'S I WORK ON AT WORK. THE WIRES ON THE BOTTOM SIDE IS FOR THE MUTE FUNCTION FORGOT TO INCLUDE IT SO I POINT TO POINT WIRED IT. THE PCB ABOVE IS CORRECT
I ALSO LAY A BIG BUILD UP OF SOLDER ON THE LOAD CARRYING TRACES TO HANDLE THE CURRENT WORKS FINE THIS IS DONE ALOT IN MACHINERY PCB'S I WORK ON AT WORK. THE WIRES ON THE BOTTOM SIDE IS FOR THE MUTE FUNCTION FORGOT TO INCLUDE IT SO I POINT TO POINT WIRED IT. THE PCB ABOVE IS CORRECT
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