How do you determine if it was overheated? Or was that in the case where you know what hte contents should be, and if what you read out doesn't match what it was programmed with, then you know it was overheated?
I have never heard of a universal Quad package programmer... And it seems the mechanical complexity would be make the design of such a beast quite daunting. A hard wired socket (to a DIP) should work if you want to build one.
I think there's a "universal" PLCC adapter for this programmer which does all the PLCC sizes up to 84 pins, but I'll need to double check. Another possibility is to wire wrap a PLCC through-hole socket to straight pin headers and tell the programmer that it's looking at the DIP equivalent to the GAL. Trade time for money...
I use the quad power Lattice GALs, and if I remember correctly the quarter power 16V8 draws 55mA or just over 1/4 watt. If you use the standard (Bipolar) device you would be at 1 Watt... And this does not include any drive current. This may not seem like much power, but that power in a plastic device which is less than 1/4 sq. in. it will cause it to get quite warm.
So it is normal for them to be warm bordering on hot in operation? The chip in question was a Lattice GAL16V8.
This sounds like a recipe for disaster to me... At least for non-destructive removal. The spec is probably (I am not at work with my data books) something like 3-5 seconds at temperature, and I suspect you are keeping the device at temperature for much longer.
I use Chip Quik. It is an alloy one melts into the existing solder which lowers the melting point. If one forms a bead on each edge of the chip which has pins, one can heat all the pins on that edge. Then by moving the soldering pencil back and forth between the beads (four sides on a PLCC) eventually you get all four sides hot enough to come loose at the same time. With the melting point lowered by the Chip Quik, I've found this safe (for the chip) and effective, until my experience with the GALs. But I don't really know for certain that they were heat damaged.
Honestly, I would have to give this some thought... a 16V8 can have up to (I believe) 17 total inputs... but then it would have no outputs. The biggest problem is if the device program reads the outputs back in as inputs. This allows internal latching which would be frustrating to figure out. The first step would be to figure out which pins are being used as outputs and which are being used as inputs... Then slowly go through the combinations keeping note of any odd behavior (such as latching). A good piece of information to have before you begin is what the GAL pins are wired to and the function of those signals (address, data, chip enable, etc.).
How would you do this? I was thinking, set up on a Proto-board with a 5V supply, momentary contact switch for the clock, switches to the inputs and LEDs on the outputs. Then run through combinations (256 for an 8 input GAL) and do some repeats of the same inputs to see if the output changes to test for whether there's a state machine implemented. Then (if it's just combinational) derive the logic using a Karnaugh map or software that solves a Karnaugh map, though I haven't any such software.
Derek
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