parallel lm3886 with 1% resistors

[ryan750]

when using a 1% tolerance resistor, for example, let's say for a parallel lm3886 and a non inverting input the worst case voltage gains is I think 23.44 and 22.56

and for example I've paralleled this two chips driving a 4ohm load.

is there any formula on obtaining the power dissipation on each IC's???

does lowering the supply voltage a little bit would compensate for the gain mismatch and possibly lowers the power dissipation below 40w which national specifies?????

[AndrewT]

use +-1% resistor but accurately match them to better than 0.1%

[abraxalito]

Originally Posted by AndrewT

use +-1% resistor but accurately match them to better than 0.1%

Yep, that's a good idea. However one caveat - 1% resistors tend not to have such good temperature coefficients as 0.1% ones. So the match you achieve with your DMM might well degrade at the working temperature of the amplifier.