Although there is a bit inconsistency in the pdf, it is
shown in the summary page that LM3886 features a wide
operating voltage up to 94V, which is +/-47V with split
power supply. Although there is no condition specified
I think good manufacturers should employ a safety factor
in the specs.
I'm not anywhere near afraid to feed mine with 45V, and
I don't think it will be blown up. The conditions are:
1) I employ a good practice in sinking the chip to the
heatsink. If the heatsink is hot, then make it biger.
2) My speakers are 2-way and cannot withstand too much
power anyway (about 50W average). Never measured the
speaker but I guess it won't go below 3 Ohm.
About heatsinking, it is very crucial. A trapped air due
to uneven surface may lead to the chip withstanding heat
it doesn't supposed to. IMHO, the chip failure must be
started with (slow) overheating, except when oscillate.
shown in the summary page that LM3886 features a wide
operating voltage up to 94V, which is +/-47V with split
power supply. Although there is no condition specified
I think good manufacturers should employ a safety factor
in the specs.
I'm not anywhere near afraid to feed mine with 45V, and
I don't think it will be blown up. The conditions are:
1) I employ a good practice in sinking the chip to the
heatsink. If the heatsink is hot, then make it biger.
2) My speakers are 2-way and cannot withstand too much
power anyway (about 50W average). Never measured the
speaker but I guess it won't go below 3 Ohm.
About heatsinking, it is very crucial. A trapped air due
to uneven surface may lead to the chip withstanding heat
it doesn't supposed to. IMHO, the chip failure must be
started with (slow) overheating, except when oscillate.
So if I keep the chips cool, it will be good?
I once ran the chip on +/- 50v rails, and it worked. Then, for some reason I don't remember, I disconnected the signal while the amp was on. When I went to connect the signal again, I don't remember exacly, but I got a spark from the signal plug to the jack. That went to the chip and fried it.
I once ran the chip on +/- 50v rails, and it worked. Then, for some reason I don't remember, I disconnected the signal while the amp was on. When I went to connect the signal again, I don't remember exacly, but I got a spark from the signal plug to the jack. That went to the chip and fried it.
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