Operational Temperature Ranges

IC Temperature Range

There are four classes of devices to choose from, as it applies to operational temperature range.
The Military family of parts offer the widest range possible for temperature extremes.
The Extended range family is not available for most devices.

IC Temperature Ranges
Class Lower
: Upper
Military -55oC -65oF : +125oC +257oF
Extended -40oC -38oF : +125oC +257oF
Industrial -40oC -38oF : +85oC +183oF
Commercial 0oC +32oF : +70oC +158oF

The Temperature Range table above list particular temperature ranges per class of IC devices, by device [part number] prefix.
So, if you need to operate within a particular temperature range, a different class of devices [ICs] need to be selected.
The important point to note here is that some components may not produced in each of the temperature ranges.

Integrated Circuit Series
Logic Family Commercial Industrial Extended Military
TTL 74xx --- --- 54xx
Interface 75xx 65xxx --- 55xxx
Linear LM3xxx LM2xx --- LM1xx
ECL 10Hxxx
--- 10Xxx

The tables above list, in general, the logic family types offered in the particular temperature ranges.
There are a number of "sub" TTL Glue Logic families which offer either Industrial or Extended temperature range parts.
How ever, as a rule it's defined on a per part or function basis.
There is no generic part number to call out which defines either of those type of parts.
Once a particular family is chosen than it becomes fairly easily to determine if parts are produced to a certain temperature range.

The graph shows how propagation delay changes with increasing ambient temperature, for three different TTL families.
The graph cover both Low-to-High and High-to-Low propagation delay for the military temperature range.
FAST: 54Fxx, or 54ASxx [The FAST series is considered the same as the AS series].
Schottky: 54Sxx [example 54S00].
LP Schottky: 54LSxx [example 54LS00]. Also see List of TTL Families.
The graph shows how an IC's output could shift in time based on temperature.

Propagation delay changes for military ICs over temperature

The 74xx digital logic families [or just 74 prefix] refer to a commercial operating temperature range. The 54xx part number [or just 54 prefix] refers to a military operating temperature range. Some 74xx device families may also work at the Industrial temperature range [but you have to check, there is no hard and fast rule]. So a 74xx244 works at a commercial operating temperature, while a 54xx244 which is the same logic device [maybe the same pinout, and package] will continue to operate to the military operating temperature range [which is wider]. The same is true for analog devices; an LM3 [commercial device] is the same as a LM1 device [but works to a military operating temperature range]. There are other designators which indicate the package type, but it does not have anything to do with operating temperature range. OpAmp Derating.

So, with out a lot of words ~ pick a device with a prefix to match the operational temperature range.

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Modified 1/16/12
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