Hey all, my name is Brandon and I'm new to the forums as well as designing circuitry. I have a specific circuit board that Im trying to find more of but there is only on number on it M 458 A and my research as come up with zilch. Anyone know any sources that I may be able to find some at? I attached a pic of both sides for reference. Dont mind the 4 metal wires on the bottom they were attached to LEDs. Any help would be GREATLY appreciated! Thank you in advance for your time and efforts.




Sincerely,

Brandon M. Smith

 

That PCB has a COB (chip on board) on it. That is, the real function of that PCB is determined by the program in that COB. You will not find duplicates without paying the price of the originals, nor will you be able to duplicate it.

Do you know what it does? If so, maybe you should investigate writing your own program to do the same thing.

John

 

Hate to say this, but I would just move on to the next project. This is a chip which was designed to do whatever it does and it is pretty much 99% certain you will find no information on it whatsoever.

Just to give you an example, lets assume this circuit is one of those greeting cards which plays a song whenever you hit it (this is what looks to me by looking at the pictures). That little black blob is basically a drop of epoxy placed to protect a semiconductor device which is in charge of doing everything this contraption does. If so, this hypothetical IC would have an audio amplifier, a sensor input, power regulation, most likely an extremely cheesy microcontroller, some memory, and whatever else I may be missing. This IC is what is considered to be a Mixed Signal semiconductor because it employs both analog and digital circuitry.

This IC was designed by some semiconductor designer and was eventually released to manufacturing. The cost to generate this device is in the hundreds of thousands of dollars but because millions and millions of cards and balloons will be sold, the product eventually generates a profit. And at $5 a pop, it doesn't take long.

Anyway, the point is that the design for that chip is in somebody's hard disk and rest assured they will not do squat to release any information on it. It will be a trade secret for decades to come.

If you want to know what is inside you would need to reverse engineer it and IMHO it is WAY easier to learn how to design it yourself than it is to reverse engineer it and get back the real deal.

But just for informational purposes, to reverse engineer it you would need to decap the part (remove the epoxy which is truly the easy step) and then peel the semiconductor layers one by one while deciphering the transistor structure and topology. You would need to know about semiconductor processed so you could detect what is a transistor, a resistor, a cap, and so on. Plus you would need equipment which is probably worth a couple million dollars... Like I said, it would be easier to learn how to design the circuit than to actually reverse engineer it!

But if you know what this circuit does, chances are there is a gazillion ways to reproduce it with some other semiconductor devices. And that would be quite the learning experience!

 

http://www.ebay.co.uk/itm/Greetings...015112?hash=item461f404008:g:BY0AAOxyeglTY6rX

 

That PCB has a COB (circuit on board) on it.

That was Chip On Board, Chip bonding on board.

 

I am sure that detail matters to the TS and to the outcome. Post has been edited.

 

The Chip Bonding on Board that we call "black bean" in Taiwan, because when the Chip bonding on board and it also cover with black epoxy, when we meet this kind of chip, that is no way to know what's inside the chip, unless you using the illegal method, but that is out of our discussion.

 

It was inside a old 1:64 scale beach patrol car where you would push the front tires down and the siren went and then little LEDs up top went off. As I said Inan fairly new to all this. In can design full custom car stereo setups but have never worked with circuit boards. How would one start writing your own program? Thank you for the quick reply John!