I have been pulling my hair out trying to find a datasheet for National Semi part LM1850N. I can find LM1851N which is an 8 pin ground Fault IC and I would venture to guess that my 1850 chip is just another version of that with 14 pins. Can anyone help me on this one? I sell electronic components and would be more than happy to send someone some free NOS or just new stock if they can help me find a datasheet on this one.

Regards,

George

 

Where did you find the part number LM1850N?

 

It is in the chip and the tube they came in. I bought a very large inventory for my store and I can't find this one anywhere.

 

 

Here are pictures of the tube label.

 

OK send me the bonus: http://www.idea2ic.com/GFI/GFICs.html

 

I am impressed, takao. Those chips were becoming available just when I was studying National Semiconductor. I remember them so well that I thought the photo in post #4 was a counterfeit chip.

 

OK send me the bonus: http://www.idea2ic.com/GFI/GFICs.html

As promised I will! Go to my eBay store and pick something out, or a few things within reason and I will send them to you. Message me from eBay and I will give you an email to send your info to. I have a ton of SMD components that are not listed as well as a few thousand more through hole chips and connectors that have not been listed yet so if you don't see what you want let me know.
http://stores.ebay.com/gafelectronics

Can you send me a schematic that would allow me to test one of these GFI chips to be sure they are not fake? I check all the chips I get and never had a problem in the past but poster #12 seemed to think maybe these were and I don't want to sell anything fake!

Thank You very much!

George

 

Takao beat me to it.
LM1850 is a Ground Fault Interrupter. Page 9-61 of the National Linear Data Book 1976.
I can scan the pages and send them to you. That article that takao linked to has the same drawings in the data sheet.

 

Hmm, I am mostly into microcontrollers now. The components I need are highly specialized.

Would it take a hudge effort to take a few pictures the SMD and through hole chips, with some info what kind of chips? you could put the pics on skydrive maybe.

I found the URL within minutes by the way.

I have some ICs I want to sell off myself:

64kx4bit STATIC RAM SOIC28 (a small number of tubes)
32kx8bit STATIC RAM SOIC28 (roll of tape)
LCX244 (same as 74hc244) SMD, loose
5749 same as MC1489 serial receiver level shifter, DIL

It's not urgent but they are just sitting around.
I could take a photo soon if you are interested and even put on my eBay for transaction.

 

Most of my stuff is NOS because I got a great deal on over 700 pounds of components i just could not pass up. The only items you can see a single picture of are the ones I have posted on eBay HERE

This is a group of pictures showing all the items I need to sort through and get put away in storage bins. The only stuff I have on eBay is what is in the closet picture, that should give you an idea of how much work I have ahead of me. All of the SMD are on the dining room table pictures. Your best bet is to see what I have listed on eBay. If you need any SMD just give me a list and I will see if I have any.

 

 

Takao beat me to it.
LM1850 is a Ground Fault Interrupter. Page 9-61 of the National Linear Data Book 1976.
I can scan the pages and send them to you. That article that takao linked to has the same drawings in the data sheet.

Do you have the full Datasheet for the chip? I only have around 100 of these so I don't want to put too much trouble into them. If you have a clearer picture of the schematic that would be great. If you know of a way I could hook it up quick on a breadboard to test one that would be even better!

 

Guess these chips are only used professionally.

Awesome assortment.

 

It is a very large assortment to say the least. I have every component I could ever need except the one I am looking for LOL. I will tell you what I will do for the great job you did finding the info. email me your address and I will send you a nice little assortment of chips, SMD and through hole. I can't make it too big due to shipping cost to the UK but you will have enough to have some fun.

I have another item I can't find info on that I bought 6 months ago. They are LCD displays from what appears to be a radio maybe, that based on just lighting them up so I could see what was on them. If I post it here later would you guys mind taking a look and seeing if you might be able to help? I can't offer free stuff every time so this one is just if you wouldn't mind using your awesome search skills to help. I have a part number and picture I will post after I take the wife out for valentines dinner.

Regards,

George

 

Thanks. I appreciate that. I can contact you via ebay w/ address.

Actually, 6 months ago I brought most my equipment to a local club- just a few weeks i have taken back controllers + displays + soldering station.

A few days I ordered for instance a fresh resistors assortment + some bags with LEDs.

I dont use so much DIL stuff now, as I say, what I need is highly specialized components.

 

The photos from post #6 show that a test fixture is not a trivial matter.
I must plead incompetence.

 

what about using an existing circuit breaker built with same IC- simply remove it and replace w/ IC socket.

chances are these circuits are never built discretely, only some Companies make these circuit breakers.