[rescue] Pinout for Cobalt/Sun Qube 3 Power Supply?

[Alexander Jacocks]

All,

I just picked up a fairly nice Cobalt Qube 3, but it did not come with a
power supply. I beeped out the power connector (DIN-8) on the back of the
chassis, knowing that it needs +12, +5, and -12 vdc, from the labeling on
the chassis.

Checking the continuity with the mosfets on the other side of the power
connector, on the backplane, I found the following:

Facing back of chassis
power input connector (DIN8 female)

  6   7
 1  8  3
  4   5
    2

1 probably +5vdc 4430 mosfet (middle) pins 5-8 (drain)
2 “
3 “
4 gnd
5 gnd
6 -12vdc 4435 mosfet (right) pins1-3 (source)
7 gnd
8 probably +12vdc 6690 mosfet (left) pins1-3 (source)
shield gnd

I looked up those parts, and the 4435 mosfet specifies negative voltage, so
I assumed that would be -12vdc. The 3 wires is clearly +5vdc, since the
machine says that it needs +5 at 8a. -12 at 0.5a and +12 at 1.5a are the other
voltages, I believe.

Does anyone have a working PSU that they can verify this with?

I made up a power supply and cable using a Mean Well RT85B supply and some
good quality silicone jacketed wire. I verified that nothing unexpected is
shorted. The PSU powers up fine, without the machine attached, and all the
voltages are correct. However, if I plug in the DIN8 cable, the PSU shuts
down, clearly shorted.

Any help would be appreciated.

- Alex
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