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David Farber David Farber is offline
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Default LM7815A and LM7915A metal tab or no metal tab?

I'm servicing a Behringer EUROPOWER PMH2000. The + and - 15 volt regulators
need replacing because the leads have failed. The transistor is mounted to
the chassis at a 90 degree angle and then soldered to the pc board. The
problem is that pc board fits very tightly into the chassis. The leads on
the regulators keep getting flexed with each pc board removal. Anyway, I
want to replace them because a couple of the leads have broken off. They are
packaged in a TO-220 case. The center tab is nonmetallic so it is insulated
from the chassis. Though the schematic says terminal 2 is grounded in the
7815A anyway, I was wondering if it made any difference whether or not I
purchased ones with metallic backing or ones with a plastic backing.

I just looked at the LM7915 spec sheet and it says that terminal 1 is ground
and terminal 2 is the input which is reversed from the positive regulator.
It also doesn't mention whether or not it has a metal tab, which if it did,
would have to be insulated from the chassis. Do any of you have any
experience replacing these regulators in a chassis mount situation?

Thanks for your reply.
--
David Farber
Los Osos, CA