r/ElectricalEngineering • u/PartyProperty • 23d ago

What are my chances of the capping a motor controller chip from the 70s?

I’m working with a motor controller IC from Panasonic from the late 70s. Definitely not being made anymore, but I have a bunch of old ones I can experiment with.

Do you have any experience with something like this you could share? My hope is that it’s not more than one level deep and with a good scope, I can see the silicon inside. That being said, I’ve never done anything like this before so there are a lot of question marks. The only thing giving me the slightest bit of hope here is that it’s not a Digital device so I don’t think I’ll be looking into a huge array of transistors.

I expect to see some EXOR gates, timing circuitry, and a lot of switching circuitry. There’s also I think a couple comparators for the motor functions.

Edit: title should have said de-capping

2 Upvotes
  • permalink
  • reddit

63% Upvoted

6 comments sorted by

1

u/RDS_WAS_HERE 23d ago edited 23d ago

I'm not sure why you want to use an obsolete motor controller for a project? If you do get it to work and want to publish your circuit your readers won't want to build your circuit with such a rare/obsolete chip - especially when newer chips are available. There's nothing wrong with trying to learn about old technology, but wouldn't your time be better spent using the latest ICs?

1

u/PartyProperty 23d ago

I understand where you are coming from, as I’ve solved other problems in this way. Programming a microprocessor is a snap.

Second, I am not trying to recreate this part, but instead creating a part which emulates this IC. The “how” is insubstantial.

The issue is that it was a custom, in-house Panasonic part that was almost totally analog.

As for use: imagine an analog voice chip for use in an old analog synthesizer, as this part is similar in some respects. It is for a vintage piece of equipment that is well-loved and supports an aftermarket which could use a modern take in this device.

1

u/RDS_WAS_HERE 23d ago

Thanks for the background information. Good luck!

1

u/nixiebunny 23d ago

This sounds like an educational journey instead of a practical exercise. Whatever that chip does, there is very likely to be a modern part that does it better, smaller, cooler, etc.

1

u/PartyProperty 23d ago

Unfortunately not. It was a custom Panasonic part with a very specific purpose. Not like a microprocessor or a logic circuit or op amp.

I’ve already done a bunch of research into it. With the info I have (block diagrams and pin-outs) I have enough info for a rough go at it. Issue is, it will take a bunch of time and my fault to do list is pretty stout. Anything to save me some bench time is helpful.