Unknown IC found in LG telephone set

gl6804

I had a couple of old telephone set, I decided to break them up and to see the vital components in it. In most of the set I found few ICs and upon searching for them, I come to know it's manufacture and it's complete datasheet.



This is the circuit, that I found on a red LG telephone set, it has 2 IC with no company logo, and upon searching them I found nothing about them, the third big IC appears to have a logo on it "N" shaped, but I couldn't find about it's manufacturing company.




Two small IC:
a) GL6840B
Y16

b) IL34119N
0524

One big IC:
IL34118N
0525

Does companies like LG, Sony, Bell, Panasonic,etc use IC in products that are not available in market?

If yes, then I think there are two reasons for this.

a) They do so, because the type and kind of IC they want is not in manufacturing, so they give orders to some VLSI IC manufacturing company to make for them some ICs, so that's why they are not available in market. They were produce for a specific consumer company and not for everbody else.
b) They do so, because of market strategy, they know, they have a good reputation in international and local market. People prefer to buy their product. So they include semiconductor components that are not available, so if their product goes faulty, people can't repair them, because all product components are not available. This makes their product more irrepairable and thus companies earns more profit.

Please share your view....

Almost all ICs that I have seen in the market, has some logo and their datasheets can be found.

Some parts may be proprietary, but often they are just regular parts, relabeled.
Many could be obsolete, which is why you cannot faind the datasheets.

But in this case, I think they are all off-the-shelf.
It seems the GL6804 would be a micro.
Here is something on the other two: https://www.datasheet4u.com/share_search.php?sWord=IL34118
**broken link removed**

In addition GL6840 is apparently a ringer-circuit http://www.datasheetcatalog.com/datasheets_pdf/G/L/6/8/GL6840.shtml
Generally, if there are any doubts, the circuit should be checked in detail, but I think you have identified all three components with a high likelihood.