How to decide the Temperature range of an IC??

Hi Rishi,

This chip should have no problem operating where the ambient temperature is 35 degrees C or even in the full sun light though it isn't a good idea to leave it exposed to the direct sun or the rain. If it is protected and the case is in the sun light I would expect ambient temps in the enclosure to rise to as much as 50 degrees C. This should still be acceptable for the operation of the chip but be sure to factor this temperature into your design as other components may drift from nominal values at this temperature. If self heating of the IC is an issue it will likely be covered in the data sheet with specific directions for heat sinking the component. I could find nothing about heat sinking on this IC.

John

will this ic work for an ambient temperature of 45 degrees??

All IC's operating temperatures are documented in their data sheets however there are three general temperature specifications that almost all ICs use:

Commercial  0 deg. C to 70 deg. C

Industrial  -40 deg. C to 85 deg. C

Military to -55 deg. C to 125 deg. C

There is no substitute for actual testing. A device left out in full sunlight can get extremely hot (>60C) the link discusses temperatures inside a car:

HEAT EXPOSURE IN AN ENCLOSED AUTOMOBILE

Your device may be better or worse - and then you must add the temperature rise caused by the operation of the electronics (which you can easily measure.).

You should aim never to get closer than 10C away from the maximum junction temperature for the chip you are using (to give yourself a margin for error).

You would be unwise to use a 0-70C rated part in this application and you need some testing to be sure that -40 - +85 is OK.

MK

If you have power freely available, you could maybe use a TEC.

Hi Don,

I have over 500 entries in my list of electronic acronyms and initialisms list but I do not know what TEC stands for.

John

Hi, John, I trust that you are well.

Thermo-electric cooler, also called a Peltier cooler.  Very useful in chilling detectors in telescopes, for example

Someone with all the answers

But I think he means Thermo Electric Cooler -

@ Don, kind of overkill for an RS232 driver  - TI (and others) offer 125C parts.

MK

Hey, I definitely said 'maybe.'  All semis are on their way south.  The endpoint is when the dopants get all mixed up due to entropy.  Every ten degrees warmer halves the lifetime of your solid-state device.  Funny, I've got some thermionic devices from the '30s that still work fine.  TECs are like three bux nowadays on AMAZON, though you would need to power the cooler and find a way to drain the heat away from the hot side.  Just trying to be comprehensive.  If I were all that practical-minded, I doubt I'd be bothering with this whatsoever.  If you have a natural temperature differential available you could use other TECs to power it. . .

John, you are not the only person I PO with my reliance on TLAs and FLEAs, etc.  Down here in the big city I am not the only one with this OTT trope.  It excludes the hoi polloi, and speeds communication, I suppose.  Why is being annoying so much fun?

I suggest putting this in a fair sized box with cotton balls as insulation like http://www.homeadvisor.com/article.show.Cotton-Insulation-is-Safe-Green-and-Effective.15108.html . This will mitigate the temps if you are concerned.

Clem