What does the "H" mean in Part Number UPC78M15H?

On Fri, 06 Apr 2007 20:40:51 GMT, "Michael A. Terrell" put finger to keyboard and composed:

metal

Why didn't you say that before? :-)

My paper NTE catalogue lists the following:

uPC78M05 -> NTE960 uPC78M08H -> NTE964 uPC78M12 -> NTE966 uPC78M18H -> NTE958

The package style for all the NTE parts is "11f" which is TO220.

- Franc Zabkar

On Fri, 06 Apr 2007 19:44:20 GMT, "Michael A. Terrell" put finger to keyboard and composed:

FWIW, the 1990-91 NTE catalogue lists the NTE1916 (1.5A, 15V, TO-3) and the NTE1918 (3A, 15V, TO-3) devices. Both are still available at ...

Datasheets:

- Franc Zabkar

Yes, that is correct.

National Semiconductor did use the H suffix to denote the metal can. As you know, prefixes and suffixes are not standardized throughout the industry.

Here is what a Google search turned up:

UPC78M15H NEC, VoltageRegulator,

Jeff

I guess everyone posting kinda missed the original question.

To sum up;

I know what the part is. I know who makes it. I know what the subs are for it. I know what is available for info on the net.

I need to know why NEC put the H at the end for this part to denote it was different than a UPC78M15.

Someone who has NEC reference info from the 90's would probably have this info.

Thanks for everyones input, but I still do not have an answer to the original question.

- Tim -

The simple fact is, they did it because it suited THEIR needs at the time. Different OEMs use different conventions to identify their parts. Generic numbers get crap added on to mold it to fit their normal scheme. You can dig, beg and conjure all you like, but that is what it all boils down to. They need a number that fits their system, that can still be identified as a generic part.

the guy

the

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can. As you

industry.

it

Here is the listing of NEC linear reg device types.

Generally, for single output NEC 3 terminal thru-hole fixed regulators; character A following type number = output max current up to 2A. eg uPC24Axx character L following type number = output max current up 100mA eg uPC78Lxx character N following type number = output max current up to 300mA eg uPC78Nxx character M following type number = output max current up to 500mA eg uPC78Mxx no intermediate character means output max current of 1A eg uPC78xxA

The characters following the xx part are not explained anywhere but it can be deduced from the datasheet that the 'A' (as in uPC78MxxA) refers to a better line/load regulation than a standard reg. (as in uPC78Mxx which are no longer manufactured I think).

The appended 'H' (when following the 'A') does not appear to mean very much other than a package type either TO126 or MP-45G. There is sometimes an 'F' after the 'H' but there does not seem to be any real significance for the end user in this character.

All in all, the appended characters don't mean anything you should concern yourself with. The real characters which mean something to the user are the intermediate ones.

Hope this explains everything. If not, then you should get further explanation from NEC.

Natsemi

both

was

regulator.

series

sure

According to the June 1972 Natsemi data catalog (their very first I think) the LM309 was released in a solid kovar TO5 header and a TO3 package. The LM340 data shows a TO220 and a TO3 package. The LM320 is only mentioned briefly in the New Products section at the end and shows only a TO5 and TO3 package.

Looking at the Logo/part number section of a 1990 IC Master for NEC, it says that H is the Package code for TO-220.

But that book does not have any NEC voltage regulators. Neither does a 1991 NEC product selector guide. Looks like they got out of that line, or (perhaps) quit marketing them through distribution.

Mark Zenier snipped-for-privacy@eskimo.com Googleproofaddress(account:mzenier provider:eskimo domain:com)

OK, that really does help me a lot. I suspect the replaced part is not performing it's job properly. It supplies the front panel control electronics power in this receiver. If the "H" does have to do with load regulation, it may be giving unstable power to the panel.

I think I should try to find a proper part and sub it in.

Thanks for your post.

- Tim -