From: William Couture <bcouture@gmail.com>
To: Microcontroller discussion list - Public. <piclist@mit.edu>
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Date: Sun, 12 Sep 2021 07:33:27 -0700
Subject: [EE] LM1084 regulator question
Thread-Topic: [EE] LM1084 regulator question
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Hi!

I need about 3A of 5V, with a 24V supply.  I'm trying to use a LM1084 in a
TO-220, which is
rated at 5A output.

However, when I try to pull more than about 250mA, the regulator becomes
very hot and I
start getting dropouts.  A heatsink does not help.

I have an electrolytic capacitor on the output, not a tantalum like in the
datasheet, could that
be the problem?

I tried putting a 7805 in the circuit (with appropriate pinout changes) and
it's fine up to 1A,
so the problem is the LM1084 itself.

If the LM1084 will not work, can anyone suggest a low-cost circuit to get
3A or so of 5V
from 24V?

Thanks,
   Bill

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