Can anyone identify this 16 pin IC?

[bigal_scorpio]

Hi to all,

I just came across some ICs in my box that I can't figure out at all.

There are sometimes no numbers on ICs but these have the opposite problem.

However I type in the numbers on the net I cannot get a definitive answer. Can anyone out there give me a certain identity on these ICs?

Al

 

[DerStrom8]

Don't you already have a thread here about this question?

https://www.electro-tech-online.com/threads/can-anyone-identify-a-54-series-ic.42596/

 

[bigal_scorpio]

Wow mate, you know my posts better than I do!

Seriously I had forgot about posting that, but after all its 4 years ago so you can forgive me a bit.

Al

 

[DerStrom8]

Oops, I'm sorry about that! I didn't even realize that thread was from 4 (not 6) years ago! I thought it was just from last month

I had run across it at one point. Can't remember when or why, but I got a sense of déjà vu, so I looked it up

Hahaha, I apologize if that post came across as rude. And yes, I can forgive you for forgetting

Best wishes,
Matt

 

[crutschow]

Don't recognize those numbers. They may be a custom number from the user of the device to hide it's function.

 

[audioguru]

The IC might be an ordinary one that has a "special" number so that replacements can only be bought from the company making the product they are used in. Then they can charge a very high price for the replacement part.

Maybe the IC is a custom one that nobody else uses. Then again they can charge a very high price for a replacement.

 

[ronv]

If your looking for a guess mine would be a 54174.

 

[bigal_scorpio]

If your looking for a guess mine would be a 54174.

Hi Ron, Can you think of a simple way to test if it is that part?

Al

 

[ericgibbs]

hi Al,
It could be one of these, ref pdf.

Where did you find them.?

E.

 

[bigal_scorpio]

Hi Eric,

Yes it could be that. I only rediscovered them when sorting my box but I have had them since they were given to me in a job lot from a friends dad.

If they are any use to anyone on the site then I will happily send them for free.

I just like to know what things are, I must be a little OCD I guess.


Al

 

[ericgibbs]

hi Al

connect a 2mhz xtal across pins 1 and 2 , use a scope to check that the osc runs OK

E

 

[bigal_scorpio]

Hi Eric,

No scope at the moment mate. My mate in Bridlington still has it.

Saying that I have been tempted lately to get one of the new tiny hand held ones. Are they any good, the cheaper end ones that is?

Al

 

[throbscottle]

You could test the 42c40 hypothesis by connecting a resonator to the xin/xout pins and see if there are resonations. 1897 looks like a date code.

(edit: whoops, didn't read to end of thread before posting - someone beat me to it)

 

[4pyros]

My guess is some old RAM.

 

[Mr RB]

Yeah, like some old video RAM from a early 80's video card with 4Mb RAM etc? In late 80's they went to those long DIL chips with 22 pins or something.

If there's a matching set of 8 or 12 ICs in your junkbox they could be old RAM chips that you pulled from the sockets (in the good old days they put chips in sockets in PCs, before everything became "throw away").

 

[atferrari]

My guess

Just guessing

It is a 42C40P - batch from year 1989 14th week.

HB could be the code for the country where the foundry was.

In 1897 this chip was not in production.