I had a DMD in my TSPP have a SOT23 zener diode go short. It was pretty obvious the part was bad as I think it was visually blown on the DMD board. I used a traditional glass axial zener and tacked it down to the pads. Powered up and then a capacitor and fuse exploded. There was more stuff wrong with the HV regulation.

I said fudge it and bought a used DMD for really cheap on ebay. I made sure to get one that was not doing voltage regulation with SMT parts on the DMD board as the the voltage supply they where making on the DMD board was available from the HV power supply in the head of the game. Ended up having to fix the HV power supply too in the head too.

its a little chippy to go logic level to high voltage for driving columns or row whatever it does.

https://www.mouser.com/datasheet/2/268/HV9308%20B072213-968130.pdf

So this happened today. Turned on world challenge soccer, pop noise and that smell. Don't think that i am not going to try and fix it.

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the display board blew the fuse violently. I don't want to hook it back up in case it damages to HV regulators. I think I am going to buy a color DMD for TSPP and move that display into world challlenge soccer. I will see if I can decode any component marking on mine later.

if you are buying used DMDs on ebay or whatever. I would avoid this one with SMT voltage regulation. Some are lot easier to work on. When the electro caps puke the solder leads are under the soldered in place glass which makes replacement a chore. I know some years ago i had to replace those caps and i did hack job tacking them down to the solder side. The electrolytic juice may not have been cleaned up well enough and eventually HV drew an arc over those mess of 27k voltage dropping resistors. Kind of weird they used like eight small resistors like that. Guess they had their heart set on 0805 package.

Diagnosis on mine is...

Z1 went short and then smoked set of eight resistor until the fuse blew.

I tried to fix one these before with the same bad z1. I replaced it with the leaded diode and it still didn't work. I gave up at that point.

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Check some of the sega or de game manuals. I seam to remember at least some had multiple manufacturers display board schematic included.

I will say it again. Fudge these babcock ones...

even tho the schematic does not match exactly the power input area looks to be the same. Babcock had a few board revisions but I think power input stays the same. So I would ~ think ~ those zener diode values are correct. I think they make sense as to what they are trying to do on board.

The blown Z1 on my babcock board has markings I was not able to decode to any zener diode manufacturer to get a specific value, but I think the schematic is right.

In my board the bank of eight 27K resistor burnt when the z1 diode shorted. Might want to check those resistors in your game. (R1 * R2 * .... ) / (R1 + R2 + ...) = paralel resistor value. 3.38K if i punched it in my calc right.

*** EDIT ***

Tommy was the manual i was thinking of that has the different display driver schematic. They list a BABCOCK version but quick glance does not look right.