From: Dwayne Reid <dwayner@planet.eon.net>
To: pic microcontroller discussion list <piclist@mit.edu>
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Date: Mon, 18 Oct 2021 13:26:02 -0700
Subject: [EE] Looking for low-temp version of LM317 or LM317HV
Thread-Topic: [EE] Looking for low-temp version of LM317 or LM317HV
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Good day to all.

I'm working on a project that has to operate at automotive=20
temperature range.  That is: -40C through 85C.  The original design=20
called for a LM317 but the datasheet says that is good only down to=20
0C.  I do have ancient experience where a LM317 went intermittent at=20
low temperatures.

There is the LM217 which is good down to -25C and the mil-spec=20
version (LM117) good down to -55C.  But the LM117 is way too=20
expensive for this project.

Total current is quite low - less than 75 mA.  Maximum in-out=20
differential is less than 30 Vdc.  I would prefer the TO-220 package=20
if possible.

This is being used in an isolated 4-20 mA transmitter as originally=20
published by Stephen Woodward.  The internal reference voltage of=20
1.25V is important in this design.

Can anyone suggest a suitable alternative?

Many thanks!

dwayne

--=20
Dwayne Reid   <dwayner@planet.eon.net>
Trinity Electronics Systems Ltd    Edmonton, AB, CANADA
780-489-3199 voice   780-487-6397 fax   888-489-3199 Toll Free
www.trinity-electronics.com
Custom Electronics Design and Manufacturing

--=20
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