is the SPD3303X designed specially poor ? when it comes to ESD or other unwanted unlucky hight voltage events
between the DC - AC - Chassis ??
yesterday i killed BOTH my SPD3303X due to an arc over event in the lab to mains.
and i mean it took me 9hrs tracking and replacing parts in them, that much was found dead so far,
List : TL072 shorted, 7815 shorted, Ethernet ic shorted, IRFP150 shorted, IC inside fan shorted,
4k7 in gate drive, and a 100nF cap in gatedrive shorted,
small signal pnp for gatedrive shorted, 6.3A fuses blown,
last thing to solve : ch3 output not going on, complex logic trying to trace the idea behind all the transistors, diodes and zeners involved in this,
one reason for it to be very complex is the LED control, it is a 2 pin led, 2 color, red green,
the green do go on when i push output enable, so signal from optocoupler is there, however no gate drive, to power board,
and the power board is confirmed working (the other unit works now 100%, so i got one to compare with)
any one with a schematic snip of the ch3 logic ?
picture attached, i need to know the part types of the four SOT23 devices,
otherwise i need to remove them one by one from my working unit to prove their function,
and then add what ever i feel fit the feature