IC regulator question

[Esteban]

Well, I'm dissambling tons of old PCB from different kind of equipments. Yesterday, I show in thread "Recycling components" a Motorola MC7805CP volt. reg. dated 1977. I bought many of different brands and is very rare obtain the 5 V, ever shows 4.80, 4.90 and also tends to fluctuates on tester. This old IC is platted on gold, pins and dissipator body (back part). See the accuracy, also don't fluctuates on tester! Seems we buy garbage in comparisson with this...

[Geo]

Hi Esteban. I had the same problem with some transistors. One oscillator with BC184 with gold pins worked at 600khz. The same oscillator with simple BC184 (maybe from china or Taiwan or... ) and the same coil don't work up to the 350 Khz

[Esteban]

Hi Esteban. I had the same problem with some transistors. One oscillator with BC184 with gold pins worked at 600khz. The same oscillator with simple BC184 (maybe from china or Taiwan or... ) and the same coil don't work up to the 350 Khz

You're right. I have the luck and bought more than 100 old PCBs, and obtain good components, Dale 1% resistors, MKT capacitors, 2N2222A Motorola transistors (try in your MD oscillator and you feel the difference), seems that some transistor can't carry the job and stoops.

[Max]

You're right. I have the luck and bought more than 100 old PCBs, and obtain good components, Dale 1% resistors, MKT capacitors, 2N2222A Motorola transistors (try in your MD oscillator and you feel the difference), seems that some transistor can't carry the job and stoops.

Hi,
yes I see that too very often with some old stuff I have: old parts were made usually with much more care than in the 80's , 90's and last years.

Some 70's parts are excelent still today and very good made, first quality e.g. metals etc.

The problem is that unless you find a stock of old cards, pcbs to dismantle or some NOS stock you'll never get them in big quantity.

Today parts, but same apply to most 80's made parts also, are made with less care... companies moved to taiwan and china and other places (philippines, malaysia, korea, singapore etc etc etc) lot of production of ics and similar stuff... semiconductors.
Then I must say that old parts made e.g. in the UK , West Germany or US were MUCH better than that things, even if with same label, as Geo reported.

I saw similar also for silly things like germanium diodes! (you know about that , uh ?)

What to say... that's another gift of global economy!

Kind regards,
Max

[Carl-NC]

Having been an IC designer, I can say without a doubt that semiconductors made today are higher quality than those made in the 70's and 80's. Most semis are made in Taiwan (TSMC) or the USA, and a number of smaller fabs scattered around. But most plastic packaging is done in Philippines, Singapore, etc., which is why you see those names on the package.

Regulators (like all chips) have statistical variations, so it's not surprising to see some that are a little low, a little high, and dead on. The datasheet should have limits for these. Also loading affects it... try putting 100 ohms on the output and see if it maintains 5.00v.

- Carl

[Max]

Having been an IC designer, I can say without a doubt that semiconductors made today are higher quality than those made in the 70's and 80's. Most semis are made in Taiwan (TSMC) or the USA, and a number of smaller fabs scattered around. But most plastic packaging is done in Philippines, Singapore, etc., which is why you see those names on the package.

Regulators (like all chips) have statistical variations, so it's not surprising to see some that are a little low, a little high, and dead on. The datasheet should have limits for these. Also loading affects it... try putting 100 ohms on the output and see if it maintains 5.00v.

- Carl

Hi Carl,
I do not agree. I mean it's more complex thing, what you say is right in a big number of cases, no dubt about, expecially for digital stuff and newer parts like CPUs and MCUs.
Of course, quality checks are well more advanced than before... but the problem if quality of materials employed in some low-end productions.

I do not agree that in these cases the semiconductors are made in the west and then assembled in plastic in the east. It isn't just a packaging issue, but a whole production issue.

That thing you wrote can be true for e.g. MCU things... you made semiconductors (with proprietary technology and know-how) in the e.g. USA then send the "stuff" to taiwan just for packaging... cause the company simply don't wanna pay extra taxes for the "dirty work", I mean eco-issues on plastic molding, epoxy and a number of toxic wastes, that you can made everywhere in the world if you just make there a plant and put inside some low-skilled operators.... , pay less and have less pain... so the big player uses some plant in the east for packaging of that things.

Not true for simple stuff like transistors, regulators etc.... most of them today are really made 100% in the host country, then branded and sold by big semiconductor companies. Reason is quite simple...the reality is that the key products are always made in-house both research and production...cause there are secrets that must be protected from unwanted eyes...but obsolete and well-known things (like a 7805 regulator) you can do everywhere cause there's nothing to steal anymore, all players knows how to clone one... and most east based companies make superb clones of them with no problems at all.

In some cases there's a clear drop in performances from 70's made part to today stuff, that's my experience similar to Esteban and Geo about.
The keywords are materials and processes....
In particular, some old stuff, old transistors, old regulators and old e.g. germanium diodes an simply not comparable with today made stuff... here and there in east, simply no way for reason explained.

Anyway, just my opinion about.

Kind regards,
Max

[Esteban]

Having been an IC designer, I can say without a doubt that semiconductors made today are higher quality than those made in the 70's and 80's. Most semis are made in Taiwan (TSMC) or the USA, and a number of smaller fabs scattered around. But most plastic packaging is done in Philippines, Singapore, etc., which is why you see those names on the package.

Regulators (like all chips) have statistical variations, so it's not surprising to see some that are a little low, a little high, and dead on. The datasheet should have limits for these. Also loading affects it... try putting 100 ohms on the output and see if it maintains 5.00v.

- Carl

Starts with 5.00 V and when resistor is hotting stay in 4.99. Was in this voltage 1 minute. The battery I used is deffinitively bad and cheap, and rapidly discharge to 7.90 volts. Even with this voltage stay in 4.99 during the 1 minute test. Here now is 34.3 ºC. See the 2 pics.

[Esteban]

Hi Carl,
I do not agree. I mean it's more complex thing, what you say is right in a big number of cases, no dubt about, expecially for digital stuff and newer parts like CPUs and MCUs.
Of course, quality checks are well more advanced than before... but the problem if quality of materials employed in some low-end productions.

I do not agree that in these cases the semiconductors are made in the west and then assembled in plastic in the east. It isn't just a packaging issue, but a whole production issue.

That thing you wrote can be true for e.g. MCU things... you made semiconductors (with proprietary technology and know-how) in the e.g. USA then send the "stuff" to taiwan just for packaging... cause the company simply don't wanna pay extra taxes for the "dirty work", I mean eco-issues on plastic molding, epoxy and a number of toxic wastes, that you can made everywhere in the world if you just make there a plant and put inside some low-skilled operators.... , pay less and have less pain... so the big player uses some plant in the east for packaging of that things.

Not true for simple stuff like transistors, regulators etc.... most of them today are really made 100% in the host country, then branded and sold by big semiconductor companies. Reason is quite simple...the reality is that the key products are always made in-house both research and production...cause there are secrets that must be protected from unwanted eyes...but obsolete and well-known things (like a 7805 regulator) you can do everywhere cause there's nothing to steal anymore, all players knows how to clone one... and most east based companies make superb clones of them with no problems at all.

In some cases there's a clear drop in performances from 70's made part to today stuff, that's my experience similar to Esteban and Geo about.
The keywords are materials and processes....
In particular, some old stuff, old transistors, old regulators and old e.g. germanium diodes an simply not comparable with today made stuff... here and there in east, simply no way for reason explained.

Anyway, just my opinion about.

Kind regards,
Max

I agree. Some chips of today maybe are based on more modern assembling technic, but not very good material. For me, this MC7805 CP regulator by Motorola is exceptional, maybe was ordered under stricts procedures, body and pins platted on gold. Maybe this is not very important, but I see here more dedication... .

[Esteban]

Also, the IC maybe works for years and voltage is good today! Was "cooking" in the PCB for some years.

[Esteban]

Here photo of 2 equal equipments. One uses the Motorola MC7805CP and the other is marked as uA 7805, manufactured
on 8014, 14 week of 1980. This was made in Korea (assembled). I know that was assembled in Korea by USA
and matrix machinery. Maybe this not mean "Made in Korea".

[Esteban]

Assembled in Korea... uA7805 of 1980.

Stay quiet in 5.02 V with load 99.6 ohms without variations. Tested for 1 minute at 34 ºC.