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6-2
CIRCUIT DESCRIPTION
(3) For digital signal input (RGB3)
Auto
Picture
IC8701
Panel Link
receiver
IC7011
Scan
Convert
IC8501
Sharpness &
screen Size
IC7506
ϒ
Process
On screen
IC9004
Signal
Select
IC7503
In the case of RGB3 input, the digital RGB signal input from the PL1 connector is in the serial data mode.
Therefore, these serial data are converted into the parallel data at the panel link receiver of IC7011.
Since then, the signal input is entered in IC8701, where the same operation is performed as described in
(2) above.
(4) Analog filter block
The video signal passes through the low-pass filter (LPF) before it is processed for digital conversion at
the AD converter. The LPF comes in 3 types. After passing through the LPF, each input signal is selected
by the respective switching ICs (IC6001, IC6002, IC6003, IC6004, IC6005, IC6006) and the resultant
signal is applied to the AD converter of IC6502. The selected signal is output from the I/O extension IC of
IC6007. This IC6007 is controlled by the microcomputer of IC9501 through the I2C buses of SCL2 and
SDA2.
(5) AD converter block (IC6502)
IC6502 is an IC intended to convert an analog RGB signal into an 8-bit digital signal. (For this output,
however, a total of 48 lines, i.e. 8 bits ÉG 2 for each color, are used.) In addition to the functions of the AD
converter, this IC is provided with those of an analog AMP and PLL/VCO. Each function is controlled from
the CPU through the three buses (SID2, SIK2, CSAD2).
The analog AMP incorporated in IC6502 is used for the adjustment of contrast and brightness, and also
for that of white balance to be conducted in the factory adjustment mode.
In addition to the video signals, both horizontal and vertical sync signal inputs are also applied to this
IC6502. Based on these sync signals, the video signal sampling is conducted with the sampling clock
signal produced in the built-in VCO. The sampling frequency differs according to each signal input.
Since IC6502 is not used in the case of the RGB3 input, the output (video output, sync output, clock
output) is treated with high impedance through the 3-wire bus.
(6) Definition conversion processor block (IC8501)
In IC8501, the SDRAM (IC8503, IC8504, IC8505) is used to convert the XGA signal into the VGA signal
or equivalent. In addition, screen size modification for normal, full, etc., is carried out. Movement of the
screen position is also conducted. IC8501 is also in charge of color temperature control for the user
menu.
The memory control clock produces 80MHz at X8501 and the generated clock signal is distributed to
IC8501 and each SDRAM.
The clock signal input applied to IC8501 and the horizontal and vertical sync signals come in two sys-
tems; the one synchronized with the input signal (input side) and the other one synchronized with the
signal (output side) to be fed to the plasma display module. The clock signal on the input side is fed from
IC7007, while the clock signal on the output side is fed from IC9005. For both input and output sides, the
sync signals are supplied from IC9004.
For the video input as well as the clock on input side and horizontal sync, the input terminals can differ
according to the input signal mode. In the case of RGB input for video signals, DVD, and VIDEO, inputs
are transferred through Pins 162 to 185. In other cases, inputs are transferred through Pins 190 to 248.
Содержание PlasmaSync PX-42VM1G
Страница 10: ...NEC Technologies PlasmaSync Plasma Monitor User s Manual...
Страница 118: ...METHOD OF DISASSEMBLY 7 1 1 Diagonal view of the main unit rear panel...
Страница 123: ...METHOD OF DISASSEMBLY 7 6 A01 C04 4 MAIN PWB ASSY 1 Remove the screw C04 and take out the MAIN PWB ASSY A01...
Страница 124: ...METHOD OF DISASSEMBLY 7 7 5 POWER UNIT 1 Remove the eight screws S02 and take out the POWER UNIT A10 A10 S02...
Страница 128: ...METHOD OF DISASSEMBLY 7 11 9 BRACKET MAIN 1 Remove the six screws S02 and take out the BRACKET MAIN M11 S02 M11...
Страница 134: ...MEMO...
Страница 135: ...DISASSEMBLY 8 1 S01 S01 M05 M06 M07 A06 S01 S01 S01 S01 S01 M01 M04 M06 S01 A04 P01 M03 S10 S03 S01 M02...
Страница 137: ...9 1 PACKAGING Packing details A Safety bracket SASSY B 1 Safety bag SASSY...
Страница 139: ...D CUSHION CARTON BOX 9 3 PACKAGING...
Страница 141: ...9 5 PACKAGING F CARTON BOX OUT...
Страница 147: ...CONNECTION DIAGRAMS 11 1...
Страница 148: ...BLOCK DIAGRAMS 12 1 MAIN PWB BLOCK...
Страница 149: ...BLOCK DIAGRAMS 12 2 VIDEO BLOCK...
Страница 150: ...BLOCK DIAGRAMS 12 3 AUDIO BLOCK...
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