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SE / SE30 PSU voltages okay?
Posted by: feltel on 2023-06-02 06:44:14
I'm in the process of re-assembling my new SE30. I recapped the analog board an and did an initial smoke test. An old HDD did spin up, so I think I didn´t screw up the analog board while recapping. I did not touch anything inside the PSU at the moment. I checked the voltages with nothing attached, i.e. the analog board and the Sony PSU connected. Nothing else. The screen wasn't driven due to not connected main board. On the HDD power cable I measured 5,56V on the 5V line and 12,09V on the 12V line. Is this "in spec" when nothing is connected? I know the 5V line is adjustable somewhere on the analog board but I would get advice before adjusting anything in this regard.
Posted by: Nixontheknight on 2023-06-02 09:20:29
I'm in the process of re-assembling my new SE30. I recapped the analog board an and did an initial smoke test. An old HDD did spin up, so I think I didn´t screw up the analog board while recapping. I did not touch anything inside the PSU at the moment. I checked the voltages with nothing attached, i.e. the analog board and the Sony PSU connected. Nothing else. The screen wasn't driven due to not connected main board. On the HDD power cable I measured 5,56V on the 5V line and 12,09V on the 12V line. Is this "in spec" when nothing is connected? I know the 5V line is adjustable somewhere on the analog board but I would get advice before adjusting anything in this regard.
the 5V seems a little high, but you said it's without load, attach an SE or SE/30 analog board then measure from the Molex connector to see if you still have 5V and 12V
Posted by: feltel on 2023-06-02 09:41:25
That is what I did and the voltages I took from there.
Posted by: zigzagjoe on 2023-06-02 09:45:19
I'd advise not checking voltages without some dummy loads or a logic board connected. There's more or less nothing on your 5V line right now so I would expect it to float high as it seems to be doing.

A simple test would be to jumper in an automotive bulb turn signal or brake bulb to the 5V line. It won't draw as much as the logic board will, but it will put enough of a load on the line.
Posted by: feltel on 2023-06-02 09:48:16
Thanks. I'll have a look if I can hack something together. I dont want to connect the precious SE30 motherboard till the voltage situation is okay. Maybe it is already ok, but I want to be sure not to fry the board.
Posted by: feltel on 2023-06-02 10:28:38
I connected an Molex Y-cable to the HDD power cable. From there I connected an Molex to 2*SATA power adapter and connected two old SATA notebook drives. Both do spin up and I measure 5.10V on the 5V line now. The voltage is stable for ten minutes now. I think it is safe to connect the motherboard. So around 5.5V with nothing connected other than an bare analog board is a safe bet.
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