LM399H and LM399AH difference

[AlfBaz]

I remember reading in one of the many ref posts here, somebody suggesting the LM399AH was preferable to LM399H. I don't remember the details, possibly something to do with being able to supply less current to the heater... despite looking around (including data sheets) I cant seem to find the original post or any data on the topic. Anybody shed some light on the subject?

[Andreas]

possibly something to do with being able to supply less current to the heater...

I guess you mix it up with the LTZ1000A which has a different isolation against the LTZ1000 (non A).

With best regards

Andreas

[AlfBaz]

I guess you mix it up with the LTZ1000A which has a different isolation against the LTZ1000 (non A).

Ahh yes. That explains why I couldn't find it again. Thanks Andreas

[AlfBaz]

The LM399AH is simply tested more, and is guaranteed to meet better specs.  The LM399 could also-- but those are not tested for that-- and you have to do this testing yourself.

Thanks for that info.
Looking at the datasheets there seems to be only columns for 399H/399AH and 199/299
Is it that the specs are the same but the AH has more guaranteed specs than the H?
In other words is it "guaranteed to meet better specs" or "guaranteed to better meet specs"?

[wraper]

The LM399AH is simply tested more, and is guaranteed to meet better specs.  The LM399 could also-- but those are not tested for that-- and you have to do this testing yourself.

Thanks for that info.
Looking at the datasheets there seems to be only columns for 399H/399AH and 199/299

You didn't read the datasheet carefully. In the ELECTRICAL Characteristics table (page 2, tempco).
http://cds.linear.com/docs/en/datasheet/199399fc.pdf

[AlfBaz]

You didn't read the datasheet carefully. In the ELECTRICAL Characteristics table (page 2, tempco).

Thanks wraper, to busy looking at the outskirts of the data tables looking for differentiation and not within them