XOCECO PH42T7, Service Manual

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18
Diagnose and service of panel
1. Block function of panel
The power supply board, Logic board, X drive board, Y drives board, Logic BUFFER (E, F and G)
and Y BUFFER (upper and lower) of the PDP panel.
* Power supply board
: to supply power for the screen, other functional modules on the screen, our
own main board, and video frequency processing board.
* X driving board
: to produce and provide driving signal for X electrode according to the time
sequence signal sent from logic board.
* Y driving board
: to produce and provide driving signal for Y electrode according to the time
sequence signal sent from logic board.
*Logic board:
to process the image signal sent from the main board, to produce addressing signal
and to provide driving signal for X and Y driving boards.
*Logic BUFFER board:
To convert the data signal and control signal sent from the logic board into
the signals required by COF.
*
Y BUFFER board:
to transmit the scanning signal from the Y driving board to the screen, which is
divided into upper and lower parts.
*
COF:
to convert the signal sent from the logic BUFFER board into the address signal used by the
screen.
2.Trouble diagnosis:
2.1 The screen is not bright:
a. Check if the power supply plug from the power filters board to the power supply board is well
inserted into the socket. If not, plug it in.
b. Check if the fuse on the power supply board is blown up. If yes, replace it for a good one.
c. Remove our main board and the video frequency processing board, ground the pin 4
Power supply board
X drive board Y drive board
Logic board
Logic BUFFER (E)
Logic BUFFER(F) Logic BUFFER(G)
Y BUFFER (upper)
Y BUFFER (lower)
COF(7 piece)