Solid State Guitar Amp Forum | DIY Guitar Amplifiers
Solid State Amplifiers => Amplifier Discussion => Topic started by: exztinct01 on September 27, 2016, 03:47:09 AM
I found a spreadsheet containing some values for LM3886 design. Can anyone of you please confirm it?
It already contains data that can be used to determine proper VA for traffo and proper heatsink, and independent variables like VCC, speaker impedance and crest factor can be changed values.
Here's the site http://www.neurochrome.com/taming-the-lm3886-chip-amplifier/thermal-design/ (http://www.neurochrome.com/taming-the-lm3886-chip-amplifier/thermal-design/)
and the spreadsheet http://www.neurochrome.com/wp-content/uploads/2014/10/ClassAB_Calculator.xlsx (http://www.neurochrome.com/wp-content/uploads/2014/10/ClassAB_Calculator.xlsx)
Looks like he has done all the hard maths for you so go for it. :tu:
Unless you are going to flog the amp with extreme levels continuously there is no need to get it exact.
Even with the best heat sink I think the limiting factor would be the surface area of the Tab on the chip.
The laws of physics will dictate the thermal transfer through that tab would be limited.
Phil.