Need help identifying this part. may be transistor. PHOTO

Thread Starter


Joined Mar 22, 2016
upload_2016-5-15_17-17-49.jpeg Can someone help me identify the part on this board that is in the lower right hand corner? This board is from a 4 pin HEI ignition module. In the original circuit gm used a mj10012 npn darlington. I have looked all over the internet to find this(pictured) part but to no luck. what type of package is this? and can someone point me to a site on the internet that has or makes these, as Id like to find out more info on them.

Thanks again to everyone for your help.




Joined Nov 29, 2011
Looks like we're missing some wirebonds, too. It is a Chip On Board device. Forget about trying to find one. Even if you could buy just one, you still need wirebonding capabilities to connect it. Your only solutions are to purchase another board, or to backwards engineer the board and produce it yourself, with discrete components.

Who took the epoxy dome off the board?


Joined Apr 24, 2011
You are looking at a traditional hybrid circuit, meaning the base is a ceramic substrate with silver conductors silk screened down and fired in. The dark rectangles are resistors, and the green is a glass covering/insulator, both of these also silk screened and fired.

You can see where a laser cut the resistors to bring them up to value. There is a spot for an SOIC package chip with the chip missing. The metallic rectangles are transistors, that is how they look when fresh cut from the wafer they were made on.

I've spend decades working on things like this. While the schematic could very possibly be pulled from this piece no one could guess what the part values or numbers are.