T&L Publications

well good news everybody ( Futurama )
i got the chip in yesterday and installed it.. it works now.
i let run for about 30 min,, works great.. i kinda doubted that the diodes were bad.
also i had ordered 2 of them chips, they only sent 1, i called them and they double checked, and only 1 was went, so they will send me the second one soon..
otherwise all is working..

Now you can question why it failed and if another component allowed an overstress or if the chip failed on its own. When you get the spare chip, you can use diode check on each pin WRT power and ground to look for an open or shorted pin (by comparing results between the good and bad part), that will give you some idea what may have induced the failure. If you have a curve tracer then you can get even more info.

no curve tracer..
and the power supply is over 15 yrs old..