Repair & Schematics
Panasonic Q

Power Circuit (Panasonic Q)

12min

Still very much under reverse engineering still, below are my rough notes on the general power circuit of the Panasonic Q. Things may be wrong until I have worked on more units to confirm.

AC Power Board

The AC power into the console comes in at the AC connector on the bottom right. It accepts 100V (so 110V mains like Japan and US) so if using it in the UK or similar you will need a transformer.

Power Entry (Panasonic Q)
Power Entry (Panasonic Q)
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The mains AC travels through a 2A rated fuse, through some basic filters and capacitors off to the rest of the board.

Top Lid Power (Connector P)

The left of the board has a power connector P that goes to the top lid board.

Connector P (AC Board)
Connector P (AC Board)
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Document image
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Side Board +8V / -8V (Connector K)

There is another 3 pin connector K with a ferrite bead on the cable, that sends 8V and -8V to the side board.

8V / -8V Power
8V / -8V Power
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8V / -8V Power (Side Board)
8V / -8V Power (Side Board)
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DC Board Power Connectors

The thick black and red wires on the AC power board sends AC power to the DC Power Board, along with the 5 pin IDE cable wiring on the bottom left.

Power To DC Board
Power To DC Board
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DC Power Board

Power comes from the AC Power board via the 2 thick wires for AC.

DC Power Board Top
DC Power Board Top
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IC

Identifier

Notes

IC904

2903 1119K

Probbaly LM2903 Comparator

IC905

9743A

BA9743AFV 2-channel switching regulator controller

IC906

1150S

IR1150S uPFC One Cylce Control

IC907

1150S

IR1150S uPFC One Cylce Control

Q906

6912A

onsemi FDS6912A Dual N-MOSFET

Q907

6912A

onsemi FDS6912A Dual N-MOSFET

All of the power to the DC board comes from the AC boards 2 pin AC input, which is switched on via the large relay, which is turned on when the front board sends the power on signal to the AC board to turn on that relay.

DC to AC Power (5V / -12V / 12V)

After that, the DC board sends back 5V, -12V and 12V to the AC board.

From left to right it is 5V, Ground, -12V, ??? (ground), 12V.

The fourth pin connects to ground, but I think through some inductor or shorted passive, so it isn't directly ground as such.

The 12V (pin 5) is joined directly to the Connector N to the left pin (pin 1), as well as going to the 2-pin 12V black/red wire in the middle of the board.

AC to DC Board Power
AC to DC Board Power
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Side Board 12V / 5V / 2.5V (Connector N)

The DC board also outputs 12V, 5V and 2.5V rails onto the side board from connector N (from left to right, far right being ground), when the Front Board (powered by the Top Lid, powered by AC power boards connector P) sends the Turn On signal to enable the large relay on the AC power board to send power to the DC board.

12V / 5V / 2.5V Output
12V / 5V / 2.5V Output
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GameCube Power Board Supply (Connector M)

Power to the GameCube Power Board that sends power out to the GameCube via the 2-pin cable when powered on. This is 12V DC.

GameCube Power (Connector M)
GameCube Power (Connector M)
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GameCube Power Board

The sub-board that receives 12V DC power from the DC board (connector M), and passes it to the GameCube console (connector L) when it is switched on through the AC boards relay.

It also has another 4 pin supply (connector J) that goes to the Side Board.

GameCube Power Board
GameCube Power Board
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Fan Power (Connector U)

The 2 pin wire (connector U) sends power from the side board to the system chassis fan.

Fan Connector U
Fan Connector U
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Optical Drive Power

The power to the optical disc drive coms from connector O which comes from the Top Lid (and the power to the Top Lid comes from connector P going to the Side Board).

Optical Drive Power Connector O
Optical Drive Power Connector O
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