Hitachi 51F510, Руководство пользователя

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DP-4X DIGITAL CONVERGENCE INTERFACE CIRCUIT EXPLANATION
PAGE 06-01
See Digital Convergence Interconnection Circuit Diagram for details.
The Digital Convergence circuit is responsible for maintaining proper convergence of all three colors being pro-
duced by the CRTs. Many different abnormalities can be quickly corrected by running
Magic Focus .
The Digital convergence Interconnect Diagram depicts how the Digital Convergence Circuit is interfaced with
the rest of the Projection’s circuits. The main components and/or circuits are;
•
THE DIGITAL CONVERGENCE UNIT (called DCU)
•
CONVERGENCE OUTPUT TO STKs
•
CONVERGENCE YOKES
•
MAGIC FOCUS SENSORS AND INTERFACE
•
MAGIC FOCUS activation by Magic Focus Switch on Front Control Panel or customer’s Menu.
• MICROPROCESSOR
•
RAINFOREST IC (Video Processor).
•
SERVICE ONLY SWITCH
• INFRARED REMOTE RECEIVER
•
ON SCREEN DISPLAY PATH
THE DIGITAL CONVERGENCE UNIT (DCU) (8 Sensor array).
The DCU is the heart of the Digital convergence circuit. Held within are all the necessary components for gener-
ating the necessary waveforms for correction, and associated memories for the adjustment data and Magic Focus
Data.
The Block above shows the relationship of the DCU to the rest of the set. Note that the light being produced by
the CRTs is what is used by the sensors for Magic Focus. This allows the DCU to make adjustments regardless of
circuit or mechanical changes or magnet influence, by actually using the light on the screen to make judgments.
EEPROM AND SRAM SHOWN IN FIGURE 1: (8 Sensor Array).
Each color can be adjusted in any one of 117 different locations. The internal workings of the DCU can actually
make 256 adjustment points per color. These adjustment points are actual digital data stored in memory. This
(Continued on page 2)
DIGITAL
CONVERGENCE
CIRCUIT
INTERPOLATION
X6 X6 X6 X6 X1
CY CLAMP
CRT
R
G
B
H
V
117 Points Per/Color
Light
Sensors (X8)
Sensor PWB
A/D
Data Comparator
Serial-Parallel
Converter
Timing
Controller
Stored Light Sensor Data
Technician's Eye
Error Data
EEPROM
2K Bit
MIRROR
AC Applied, Copy from EEPROM, then caculations will be made. Time, approx. 20 sec.
Calculation of other 139 points per/color
Back Up
To Video Circuits
Addressable
by
Technician
Also available;
35 Adjustment Points
9 Adjustment Points
Points
Per/Color
Via O.S.D.
117 Points Per/Color
D/A Conv.
Static Centering
Stored during Initialize
between stored data
and light sensor data
One Chip CPU
Infra-Red Decoder
Digital Cross
Hatch Gen.
Timing
Controler
Serial/Parallel
Converter
Gate Array 4000 gates
S-RAM
(256Kbit)
FAST
EEPROM
(2Kbit)
SLOW
8 bit
128 Kbit
D/A
1st S/H 2nd S/H
LPF
CLAMP
256 Adjusted
Displays CrossHatch
SCREEN
Adjust through observation
Remote
Control
Figure 1