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IIC-SCL
IIC-SDA
Power Off STBY & SUS H-SYNC V-SYNC
15V TILT SIGNAL -12V PURITY SIGNAL 15V H-STC V-STC 12V USBUSB+ SOG SEL SOG OFF H-SIZE H/V STC COIL 12V 78V R/G/B R/G/B H-SIZE MAX HSTC VSTC IIC-SDA IIC-SDA IIC-SCL 5V 5V BUZZ STBY DDC-SCL DDC-SDA 6.3V -12V
SCL SDA
5V D-SUB (SIGNAL CABLE) STC CONTROL AN5769 (IC304)
IIC SIGNAL
Power OSD
SET UP DOWN
KEY CONTROL (IC101, IC102, IC103) HEF4013BF
SUB MICOM (IC1004) MC68HC705 BDIA
EEPROM 24C08 (IC207)
5V TILT CONTROL (IC603)
PURITY CONTROL (IC603)
LEFT RIGHT
CDT
MICOM
DDC-SDA DDC-SCL CLAMP
IIC-SCL
VIDEO PRE-AMP M52743BSP (IC302) POWER AMP VPS13 (IC303)
(IC202)
CS1 IIC-SDA IIC-SCL OSD Signal (R/G/B) 15V -12V CS2 CS3 CS4 USB + CS4 CS0 USB TILT ST-IN DEG LED 15V MUTE H-SIZE AFC V-SYNC H-SYNC V-SAW EW
CONTRAST
OSD PROCESSOR LSC4515 (IC301)
R/G/B BIAS 115V
CLAMP CONTROL
D+
CS1
CS2
CS3
CS4
CS5
BLOCK DIAGRAM
15V RECTIFIER D901 H-DRV
+ +
198V 5V
SMPS MAIN (T901)
H/V SYNC PROCESSOR UPC1884ACT (IC701)
12V 12V -12V 5V 78V
D/D DRIVE (IC402, Q411, 412, 413, 414)
D/D CONVERTER (Q404)
DUMMY FBT (T702)
H-OUTPUT 2SC5047 (Q707) H-Drive Trans (T701)
F/V 28V 198V
D/D CONVER (Q503)
15V
FLY BACK TRANS (T703) H-Drive Trans B+ Control (T701)
X-RAY 15V
Switching Regulator (IC902) LINE FILTER (LF901) PWM IC (IC901)
12V
SMPS SUB (T902)
6.3V
SCL
AFC
SDA
DF
HIGH VOLTAGE PWM IC M62501P (IC501)
FBT DRIVE & SWITCHING X-RAY (Q502, 506, 507)
HD FBP DF B+ H/V DETECT
DYNAMIC FOCUS VR STATIC FOCUS VR SCREEN VR
POWER INPUT 90~132Vac 198~264Vac
(IC912)
HIGH VOLTAGE DYNAMIC FOCUS STATIC FOCUS SCREEN AFC
198V
- 14 R ABL C-BRT PURITY SUB-BRT DPM OFF G
CS0
USB HUB (P801, 802, 803, 804, 807)
D
USB CONTROL IC(IC801) MC141555
V-OUTPUT TDA8172 (IC601)
DF
POWER & DPM LED
SPCC & H-SIZE MIXING (IC401)
15V
H-LINRARITY CORRECTION (Q712, 713, 714, 715, 718)
DYNAMIC FOCUS OUTPUT LF353 (IC209)
DEGAUSSING CIRCUIT (RL902) 6.3V 28V
H-CENYERING COIL
D-FOCUS AMP
DEGAUSSING COIL
DESCRIPTION OF BLOCK DIAGRAM
1. Line Filter & Associated Circuit. This is used for suppressing noise of power input line flowing into the monitor and/or some noise generated in this monitor flowing out through the power input line. That is to say, this circuit prevents interference between the monitor and other electric appliances. 2. Degaussing Circuit & Coil. The Degauss circuit consists of the degaussing coil, the PTC (Positive Temperature Coefficient thermistor, TH901), and the relay(RL902). This circuit eliminates abnormal color of the screen automatically by degaussing the slot mask in the CRT when turn on the power switch. When you need to degauss while using the monitor select (DEGAUSS) in the OPTION SELECT on the OSD menu. 3. SMPS (Switching Mode Power Supply) Circuit. This circuit works with power of 90~132Vac/180~264Vac (50/60Hz). The operation procedure is as follows: 1) AC input voltage is rectified and smoothed by the bridge diode (D901) and capacitors (C912, C913). 2) The rectified voltage (DC voltage) is applied to the primary coil of the transformer (T901, T902). 3) The control IC (IC901) generates switching pulse to turn on and off the primary coil of the transformer (T901) repeatedly. 4) Depending on the turn ratio of the transformer, the secondary voltages appear at the secondary coil of the transformer (T901). 5) These secondary voltages are rectified by each diode (D921, D922, D924, D925, D926, D931, D932, D927) and operate the other circuits. (Deflection, Video Amplifier ,..... etc.) The switching IC(IC903) controls input-pulse-width and generates secondary voltages by sub-transformer (T902). 4. Display Power Management Circuit. This circuit control power consumption of the monitor by detecting H and V sync signal. There are Stand-by and suspend, OFF mode. When no horizontal or vertical sync signal input, the circuit consists of Q903 and IC916 becomes stand-by and suspend mode. It's power consumption is below 8W without USB function. 5. X-ray Protection. This circuit detects the rectified DC voltage comes from the FBT pin 4. If the high voltage of the FBT reaches up to about 29kV (abnormal state), high voltage control PWM IC (IC501) detects it. And PWM IC (IC501) prevent output voltage to the gate of high-voltage-D/D-convert-transistor (Q503). It stops B+ voltage supplied to the FBT (T703), and high voltage is not be generated. (In the normal state, the high voltage is about 26kV.) 6. Micom (Microprocessor) Circuit. The operating procedure of Micom (Microprocessor) and its associated circuit is as follows: 1) H and V Sync signal is supplied from the D-sub to the Micom (IC202). 2) The Micom (IC202) distinguishes polarity and frequency of H and V sync. 3) The Micom controls each OSD function signals.(H-size, H-position, V-size, etc.) 4) The controlled data of each mode is stored in itself. User can adjust screen condition by each OSD function. The data of the adjust screen condition is stored automatically. 7. Horizontal and Vertical Synchronous Processor. This circuit generates the horizontal drive pulse and the vertical drive pulse by taking sync-signal form the D-SUB (P202). This circuit consists of the UPC1884ACT (IC701) and the associated circuit. 8. Oscillating Circuit for D/D Converter. This circuit generates the saw-tooth wave which has the horizontal period by taking the output of the UPC1884ACT (IC701) . 9. D/D (DC to DC) Converter. This circuit supplies DC voltage to the horizontal deflection output circuit by decreasing DC 198V which is the secondary voltage of the SMPS in accordance with the input horizontal sync signal. 10. Side-Pincushion Correcting Circuit. This circuit improves the side-pincushion of the screen by mixing east-west wave to the output of the horizontal deflection D/D converter which is used for the supply voltage source (B+) of the deflection circuit. 11. D/D Drive & Convert Circuit. This circuit is used for supplying B+ voltage to horizontal deflection output transistor (Q707). This circuit makes to add side-pincushion correcting signal to B+ voltage. 12. Horizontal Deflection Output Circuit. This circuit makes the horizontal deflection by supplying the saw-tooth current to the horizontal deflection yoke. 13. High Voltage Output & FBT (Flyback Transformer). The high voltage output circuit is used for generating pulse wave to the primary coil of the FBT (Flyback Transformer (T703). A boosted voltage (about 26kV) appears at the secondary of the FBT and it is supplied to the anode of the CDT. And there are another output voltages such as the dynamic focus frequency.
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14. H-Linearity Correction Circuit. This circuit corrects the horizontal linearity for each horizontal sync frequency. 15. H-Raster Centering Circuit. This circuit makes the back raster stay in the center of the screen by selecting the raster centering switch (SC701) 16. Vertical Output Circuit. This circuit takes the vertical ramp wave form the UPC1884ACT (IC701) and performs the vertical deflection by supplying the saw-tooth wave current form the TDA8172 (IC601) to the vertical deflection yoke. 17. Dynamic Focus Output circuit. This circuit takes H and V parabola wave from the UPC1884ACT (IC701) and amplifies these waves to offer to the FBT (T703). 18. H & V Blanking and Brightness Control. This circuit eliminates the retrace line by supplying a negative pulse to the Video Signal. The brightness control circuit is used to control of the screen brightness by changing the DC level of G1. 19. Image Rotation (Tilt) Circuit. This circuit corrects the tilt of the screen by supplying the image rotation signal to the tilt coil which is attached to the Deflection Yoke near the CDT. 20. Earth Magnetic Correction (Purity) Circuit. This circuit corrects the purity of the screen by supplying the purity signal to the purity coil which is attached to the CDT near the front.
21. Static Convergence Control Circuit. This circuit corrects the convergence of the screen by supplying the convergence signal to the Static convergence coil which is attached to the Deflection Yoke near the CDT. 22. Moiré Reduction Circuit. This circuit reduce interference between the periodical display pattern and the CDT's slot. The positions of every other one dot video signal beams (red, green and blue beam) are shifted finely, thus reducing interference.
23. OSD Circuit. This circuit is used for performing the OSD (On Screen Display) function. When a user selects the OSD Select/ Adjustment control, the adjustment status displays on the screen. 24. Video Pre-Amp Circuit. This circuit amplifies the analog video signal from 0-0.7V to 0-4V. This circuit is operated by taking the clamp, R, G, B drives, and contrast signals from the Micom (IC202). 25. Video Output Amp Circuit. This circuit amplifies the video signal which comes from the video pre-amp circuit and amplified video signal is applied to the CDT cathode.
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