/diy/ - Do It Yourself

I want to share a lesson I learned today: Be careful when ordering certain chips from Ebay. This was supposed to be the speech synth chip used in a speak-and-spell and other 80s toys, but it's garbage with a fake label etched into it.

I built the test circuit and noticed there was a problem right away because the chip was getting hot. I went over my circuit 20 times looking for a problem then started disconnecting Vcc and Gnd wires looking for the problem. I eventually found a two pins that are supposed to be high impedance input but on my chip output Vcc.

I did some googling and found other people had been ripped off with fake SP0256. Some signs that should have been obvious: Microchip never manufactured an SP0256. The label is laser etched which wasn't done in the early 80s. The pins show signs of desoldering even though it's supposed to be new.