Why no more schematics in IC datasheets anymore?

[icko]

Yes my question are as the topic.. In old datasheets of opamp and other IC's often (simplified) schematics of the device. I have, and I guess many of you learned alot looking at these schematics.

When did the companies stop printing schematics? Maybe it's always been like this, and for example 79xx, 78xx, 5534, 741, ad797 are special cases. Anyone with a little insight in IC history who wants to share?

[Trevor White]

Originally Posted by icko

Yes my question are as the topic.. In old datasheets of opamp and other IC's often (simplified) schematics of the device. I have, and I guess many of you learned alot looking at these schematics.

When did the companies stop printing schematics? Maybe it's always been like this, and for example 79xx, 78xx, 5534, 741, ad797 are special cases. Anyone with a little insight in IC history who wants to share?

maybe they are protecting their IP from competitors or maybe they don't want diyers to copy and imitate their designs using discrete circuitry

[icko]

Trevor, that is of course my guess to. But what have changed since the old devices? Corporate secrets would been an issue when for example in old days too. I have not seen old datasheets for these devices, maybe the schematics weren't in them from the beginning.

[jaycee]

protecting against chinese IP theft most likely

[indianajo]

Datasheets still contain internal IC schematics. I have recently downloaded 33078, 4560, 4562, all have an internal schematic.
In the print age, there were 5 big US IC houses (TI, Fairchild, Motorola,Signetics, National) competing for every sale. The salesmen got paid for calls, which counted as much on a small internal shop that might buy 4 or something, as on a manufacturer that might make 1000 of something. The datasheet was always about the part, but in the back of the catalog were applications notes, where sample schematics and application tips were popularized. Newer ideas were in separate application notes, 8 1/2 x 11 one color brochures which tended to get filed in chronological order (in piles) and lost. Most of the best of these application notes ideas have made it into textbooks these days, so salesmen can assume the knowledgable corporate consumer already knows the basics.
In the internet age, marketing is much more targeted. I've started getting a brochure from farnell that has a lot of new ideas and sample parts kits, mostly for cell phones. Cell phones are one of the few markets where western engineers are actually affecting product. Entertainment engineering has moved to the far East, and the sketchy datasheets I've seen for such oriental only products as 5.1 (I don't even know the proper name) indicate a lot is going on that I don't have the language to read. Furthermore, since I might buy two of something, manufacturers have decided to limit their education effort to factories that actually might buy a thousand or two. Until this stuff shows up in textbooks, it is going to continue to be a mystery.

[Bigun]

The parts have got a lot more complex perhaps - many data sheets now only show 'simplified' schematics.

[smartx21]

Do you mean SCHEMATIC DIAGRAM or TYPICAL APPLICATIONS AND HINTS?

[smartx21]

Here is an example of an antique & complete datasheet:http://www.national.com/ds/LM/LM146.pdf.
The "Voice Activated Switch and Amplifier" suggested application is an old - and quite good - example of what can be done with the proposed device and its technology.
From all the information supplied I could resemble this circuit using a more simple - and available - quad device.

[icko]

Originally Posted by indianajo

Datasheets still contain internal IC schematics. I have recently downloaded 33078, 4560, 4562, all have an internal schematic.
In the print age, there were 5 big US IC houses (TI, Fairchild, Motorola,Signetics, National) competing for every sale. The salesmen got paid for calls, which counted as much on a small internal shop that might buy 4 or something, as on a manufacturer that might make 1000 of something. The datasheet was always about the part, but in the back of the catalog were applications notes, where sample schematics and application tips were popularized. Newer ideas were in separate application notes, 8 1/2 x 11 one color brochures which tended to get filed in chronological order (in piles) and lost. Most of the best of these application notes ideas have made it into textbooks these days, so salesmen can assume the knowledgable corporate consumer already knows the basics.
In the internet age, marketing is much more targeted. I've started getting a brochure from farnell that has a lot of new ideas and sample parts kits, mostly for cell phones. Cell phones are one of the few markets where western engineers are actually affecting product. Entertainment engineering has moved to the far East, and the sketchy datasheets I've seen for such oriental only products as 5.1 (I don't even know the proper name) indicate a lot is going on that I don't have the language to read. Furthermore, since I might buy two of something, manufacturers have decided to limit their education effort to factories that actually might buy a thousand or two. Until this stuff shows up in textbooks, it is going to continue to be a mystery.

yes i've noticed that they have different targets. As more IC's available the marketing needs to be mroe focused.


Anyway I think it's too bad that that this type of information is not available anymore. There´s lots of IC's I would like to see internal schematics, simplified or not.