CPD-420GS D98 Chassis Computer Monitor S
Contents
1. Pin Name Dir Description 1 RED Red Video 75 ohm 0 7V 2 GREEN Green Video 75 ohm 0 7V 3 BLUE Blue Video 75 ohm 0 7 V 4 RES Reserved 5 GND Ground 6 RGND Red Ground 7 GGND _ Green Ground 8 BGND Blue Ground 9 5V 5V DC 10 SGND Sync Ground 11 IDO lt Monitor ID Bit 0 optional 12 SDA DDC Serial Data Line 13 HSYNC or CSYNC _ Horizontal Sync or Composite Sync 14 VSYNC Vertical Sync 15 SCL DDC Data Clock Line Note Direction is Computer relative Monitor What is Plug and Play Currently there are several levels of Plug and Play compliance DDC1 Display Data Channel 1 capable monitors can communicate with the display adapter in only one direction through an unused line on the stan dard VGA cable The DDC1 type of communication is the type of data channel from the display to the host continuously transmitting Extended Display Identification EDID information The video adapter is told what monitor is connected and its maximum resolutions and refresh rates DDC2B goes one step further by offering bi directional communications through two unused VGA lines between the monitor and the video adapter Th2. BOARD 1 1001 5 O CN1001 DEGAUSS 25 CN 801 9 2 0670 0670 0 F601 4 R672 R671 250 LF602 FB608 C605 2 5 C604 6 eee akol Y FB607 z 0601 R603 ado C606 DEUS FB609 R602 r 1 600 CN610 2 GND CN2003 E 602 BOARD SWITCH AC INPUT D98MON Bre I E sa 10 Start Up and Active On Operation The Power Supply uses a flywheel type switch mode supply It has both PWM and RCC Resistor and Capacitor characteristics The PWM con trols the pulse width of the gate drive The RCC portion insures that the next conduction cycle starts at zero volts Therefore the gate pulse width varies and the switching frequency varies When Power switch S601 H Board is closed AC 100V 240V is ap plied to D601 full wave rectifier 160V DC 110V AC in is applied through R603 L604 and R615 to T601 5 SWITCHING TRANSFORMER Start up current is supplied from D601 half wave rectified through R613 to 601 7 VCC Start up voltage at 601 7 is approximately 12V DC 601 6 PWM 11 Once start up voltage is applied 601 6 OUT outputs PWM drive to the gate of Q602 POWER SWITCH The PWM frequency will vary between 65kHz to 120kHz depending upon input voltage and power level The PWM drive from Q602 is applied to T601 2 T601 dev
3. Board 1 1001 Board via the data bus instructs 001 to vary the DC level output at pin 3 R BKG and the P P level output at pin 20 R OUT The DC and P P levels are varied until the measured beam cur rent is equal with the level stored IC003 register Once the Color Res toration function is completed the input video signal is displayed 80V 12V TO 002 12V 80V A VCCL ICO04 dose NM V BIAS VCC R B 5 5 B F B AM CATHODES our G our BKG R305 R GND coo OUT 3 6 GND RGB DRIVE GND SDA 0050 BLK R ABL 3 BOARD CN1003 CSDA ll CSCL 6 H 5 1 1 LV lt 2 Ll HRTRC CN596 COLOR RESTORATION RUS9822 1121 4 1 99 50 GPE Graphic Picture Enhancement Overview Through the front panel GPE control this unit provides the user with the ability to choose three preset modes of picture quality 1 Standard Mode 2 Presentation Mode 3 Graphics Video Mode When the GPE button is pressed 003 OSD displays to the user that Standard Presentation or Graphics Video mode has been selected The result is a change in picture brightness in Presentation mode to a change in picture brightness and sharpness in the Graphics Video mode Standard Mode In the Standard Mode no effects to the RGB signals are performed The unit defaults to t
4. lows the monitor automatically resumes normal operation mode State Power Required Recovery Power Indicator Consumption Time 1 Normal Operation lt 130W Green on 2 Standby 15 mode 15W Approx 5 sec Green and orange alternate 3 Suspend 219 mode lt 15W Approx 5 sec Green and orange alternate 4 Active off 34 mode lt 8W Approx 5 sec Orange 5 Power off 0W 6 Failure modes See Self Diagnosis Function SELF DIAGNOSIS FUNCTION When a failure occurs the STANDBY TIMER lamp will flash a set of num ber of times to indicate the possible cause of the problem If there is more than one error the lamp will identify the first of the problem areas Status Area of Failure LED Indication 1 Failure 1 HV or B Orange 0 5 second Off 0 5 second 2 Failure 2 H Stop V Stop Thermal Orange 1 5 second Off 0 5 second 3 Failure ABL Orange 0 5 second Off 1 5 second 4 Aging Self Test Orange 0 5 second Off 0 5 second Green 0 5 second Off 0 5 second TIMING SPECIFICATION for CPD 420GS MODE 1 2 3 Resolution H x V 720 x 400 1280 x 960 1600 x 1200 Dot Clock MHz 28 321 HORIZONTAL Hor Freq H Total H Blanking H Front Porch H Sync H Back Porch H Active B Blanking V Front Porch V Sync V Back Porch V Active lines SYNC Int G Ext H V Polarity Ext CS Polarity Int Non Int Troubleshooti
5. H OUT 12V MICRO 5 0 7 1 CSU a 0504 4506 R540 Q514 C542 C541 R514 H FBP 2 Baie fA 0506 R539 502 T501 Q504 Q501 HD OUTP 0505 CN801 CN1001 i P N BOARD D BOARD 21 RUS9825 1124 3 15 99 HORIZONTAL PROTECTION AFC 62 Horizontal Size Control The HD OUT signal from Q502 and Q503 Push Pull H Drive buffer is also input to 805 8 1C805 utilizes the HD OUT signal to produce the proper PWM output frequency at pin 20 The DSP IC 1002 64 E W output through CN1001 27 to CN801 27 H SHAPE is input to 805 2 The H SHAPE parabola waveform is utilized by IC805 to control the H SIZE by altering the duty cycle of the PWM drive output at pin 20 The PWM output is applied to Q506 H SIZE REG OUT Q506 controls the amount of approximately 70 through T502 HOC Horizontal Output Coil that is applied to Q505 H OUT to adjust for correct screen raster size T504 HST Horizontal Size Transformer is utilized to sense the deflection cur rent through the H DY The voltage on the secondary of T504 is rectified by D508 and buffered by Q518 and is input to I1C805 3 805 utilizes this feedback input voltage to mix with the H SHAPE waveform to maintain and control correct screen raster size IC805 2 H SHAPE 63 805 3 Size Feedback IC805 20 PWM 805 PWM FROI H SHAPE HD 1002 6
6. 18 V 008 switches between inputs selected by the user via the front panel button 1C1001 1 Board logic output selects the input source via CN1004 2 to CN309 2 INPUT SW to the A Board The INPUT SW sig nal is routed to 8 19 SW to select the conventional 15 D Sub con nector input or to select the 15 D Sub female connector from the front panel CN309 5 VS OUT 37 The V OUT Sync signal from 1 008 21 V OUT is routed to the Board The OUT Sync signal from 1C008 22 H OUT is input to the H DRIVE BUFFER 006 8 and pin 9 006 buffers the H OUT signal which is output at pin 4 is routed to the N Board CN309 7 H SYNC The input signals are then buffered and output from 008 pin 27 R OUT pin 30 G OUT and pin 35 B OUT to 001 1C008 27 OUT STBY 5V 1 STANDBY 5V 5V 12 IC008 RGB PRE AMP M52758FP e 10 200006 RGB DRIVE 00000 20665 15 11 Na INPUT SELECT VS BOARD VS_OUT CN1004 H SYNC RGB PRE AMP RUS988 1067 3 25 99 38 RGB DRIVE The RGB outputs from 008 are input to the RGB DRIVE 001 7 B IN pin 9 G IN and pin 11 R IN The G signal is also low pass filtered and input to 1C001 10 SYNC IN The Sync on Green signal is pro cessed and output at 001 30 C SYNC as composite sync which is routed to the Board 1001 Board also provides 001 12 CLAMP and pin 18 BLK with the
7. CCP Q640 PROTECT FROM A BOARD H SYNC V SYNC HSYNCO HSYNCO P5 IC1001 MICRO PWMO R640 R632 P4 0 an C AN4 AN5 C606 CN801 P6 5 _ 6 4 ENABLE Q605 CN1001 6 C CONTROL T901 11 HV FBT D BOARD D BOARD ACTIVE OFF AND SUSPEND STANDBY 18 RUS9816 1132 4 1 99 Secondary Voltages Under Active Off and Suspend Standby modes the following voltages are produced by T601 1 The output at T601 13 is rectified by D650 to produce 145V DC used for deflection and video circuits The output at T601 14 is rectified by D651 to produce 62V DC used for video circuits The output at T601 16 is rectified by D652 and D655 to produce 9V DC and 9V 2 DC used for deflection 5 12V Regulator 605 The output at T601 17 is rectified by D654 to produce 5 5V DC used for 5 12V Regulator 605 and 6 3V Heater regulator 604 19 The output at T601 18 is rectified by D653 and D656 to produce 12V DC and 12V 2 DC used for the deflection circuits The output at T601 10 through R621 is rectified by D648 to produce the H used for Horizontal Centering The output at T601 12 through R622 is rectified by D649 to produce the H used for Horizontal Centering The output at T601 11 is used for the H and H floating ground refer ence The H and H voltages in reference to floating ground are 5V NOTE Care should be taken not to short the floating ground to the sec
8. X IC703 H DF OUT IN IN OUT X A REMOTE ON OFF H ANODE OF CRT CRT VIA RED FV LEAD TEE 156902 WN WN 192 7 2 R909 56905 711 BLK FV LEAD BOARD DYNAMIC FOCUS 84 IC1001 7 FROM N BOARD 702 712 gt V DF FROM 6 lt 1C1002 58 710 BOARD RUS9817 1116 4 1 99 Vertical Deflection Vertical Drive DSP 1002 Board 1 VSAWN outputs the vertical sawtooth waveform signal The vertical sawtooth waveform is buffered by 1007 1 2 and is routed to the D Board The vertical sawtooth waveform is then input to 401 7 V IN 401 current amplifies the vertical sawtooth waveform and outputs drive at pin 5 to the Vertical Deflection Yoke via CN501 6 1C1002 2 DCC2 provides DC reference voltage via IC 1007 2 2 buffer and is applied to IC401 1 801 13 VSAWN IC401 5 V DRIVE 85 Vertical Geometric Corrections Vertical Geometric Corrections can only be performed via the DAS Software Vertical Size and Centering are the only adjustments that can be accessed by the user via the OSD menu The Micro IC1001 via the bus communicates with the DSP 1002 1 1002 1 V SAWN outputs the necessary vertical sawtooth waveform to 401 to be applied to the Vertical Deflection Yoke 801 13 VSAWN The V SAWN waveform controls the Vertical Size by var
9. approximately 48 applied through T902 to Q902 to main tain and regulate the HV The feedback voltage is inversely proportional to the that is applied to Q902 RV904 is incorporated into the HV voltage divider network to set the HV level produced RV904 varies the HV sampled feedback voltage to IC805 12 805 19 PWM G2 Screen Voltage The G2 Screen voltage is produced by T901 8 FBT via R917 and rectified by D905 to produce the 1000V DC The G2 voltage is then routed via CN510 to the A Board to the G2 control circuit 0502 Q503 HD OUT uDC5021 end 2 R809 R911 V C8347 8011 0802 4 FROM 1901 11 ABL CN510 A BOARD HV DET CN801 R811 24 2 0908 Dl 0902 FB90 HV OUT 32 P 6 4 L902 C924 TO G2 1kV C933 300V HV 76 HV FEEDBACK C829 T901 ANODE OF CRT WW R902 3 56901 20926 4 C927 1 CRT VIA RED FV LEAD R908 R909 OQ R923 SG902 gt Y 50905 R914 D909 CRT VIA BLK FV LEAD OOO RUS9819 1118 3 15 99 Auto Brightness Limiting The ABL circuit is used to control the overall beam current and brightness of the CRT The T901 11 FBT output is rectified by D904 and filtered by C929 As beam current increases the voltage output from T901 11 de creases current is inversely proportional to the voltage This voltage via D802
10. 99 RGB CUTOFF The RGB Cutoff levels can only be adjusted via the DAS CATS software or by the Color Restoration function explained later 1001 on the board via the data bus controls 001 D A outputs at pin 3 R 4 G and 5 The D A outputs from 001 are input to CUTOFF AMP IC004 pin 1 B IN 3 G IN and 4 R IN which sets the CRT Red Green and Blue cathode DC cutoff level The output of 004 7 R CUT 10 G CUT and pin 13 B CUT clamp the CRT Red Green and Blue cathodes The 180V DC with pull up resis tors R109 R209 and R309 and D106 D206 and D306 form the voltage divider network for the R G B cutoffs respectively 41 ROZO CN309 C SYNC6O 4IC_ SYNC CLAMP 2 v BPCLP 001 BLK 8 C_BLK RGB DRIVE MAT G OUT SDA 1 8IICSDA R OUT B OUT SCL 2 6 5 RO20 CN306 R317 STBY Y 12V axe O A QOO gt 7 B IN B ABL C370 FROM 9 G IN GND 008 lt R218 C230 0 SYNC IN ep GBKG R118 C130 RBKG 80V R311 R309 TO N BOARD CN1004 TO N BOARD CN1003 4001 56001 V SOCKET 1 7 19 H1 r D305 C306 L301 LN R211 D204 C206 0205 X 1047 R209 RGB OUT LM2405 G OUT JG V R109 BOARD L201 VCC BIAS 1 eI e 8 5 R251 101 151 C106 D105 0306 V M D106 12V 004 CUT OFF GIN AMP
11. GND CFI CCP TR 7 606 IC601 POWER SUPPY CONTROL CONTROL AN8037 vC IC603 4 START UP TROUBLESHOOTING 24 Q605 REMOTE ON OFF N BOARD 1C1001 7 RUS32 1141 4 1 99 25 8037 Power Supply Controller 601 The heart or the primary section is the AN8037 Power Supply Controller 601 The following table describes the function of each pin Pin 1 TR Pin 2 OCP Pin 3 CF Pin 4 CLM Pin 5 GND Pin 6 OUT Pin 7 Pin 8 SD Pin 9 FB This is TR or Transformer Reset Similar to a demagnetization function this pin detects the falling edge of the primary waveform during relaxation period It allows the next conduction pulse only after reaching the bottom of the ringing waveform Over current protection Used to determine the overload level at which the timer latch is activated Oscillator With a capacitor determines the switching frequencies On Off times Over current protection If the voltage on this pin primary current feedback exceeds 0 18V the power supply will enter cycle by cycle current limiting mode IC ground terminal Output driver for switching transistor Q602 601 supply voltage terminal This voltage is normally 17 5V DC during Active mode and 12V DC during Active and Suspend Standby mode IC receives starting current via startup resistor R613 until the auxiliary supply is available fr
12. following conditions 1 Loss of H and or V Input Sync signals LED illuminates Orange 2 Loss of Horizontal Deflection feedback LED illuminates Orange 1 5 seconds Off 0 5 seconds 3 Loss of Vertical Deflection feedback LED illuminates Orange 1 5 seconds Off 0 5 seconds 4 If Beam current ABL becomes excessive LED illuminates Orange 0 5 seconds Off 1 5 seconds 5 If HV becomes excessive LED illuminates Orange 0 5 seconds Off 0 5 seconds 6 Loss of secondary voltages LED illuminates Orange 0 5 seconds Off 0 5 seconds 17 The Active Off and Suspend Standby modes are controlled by the RE MOTE ON OFF signal from the Micro 1001 7 Board Feedback is provided by circuit elements IC603 D631 D632 R662 Q656 and Q658 During Active Off and Suspend Standby modes the REMOTE ON OFF signal from 1C 1001 7 is L OV and is applied to Q656 turning it OFF thus turning 0658 on to disable IC652 Current flows through 0658 E R662 and D632 biasing Q658 This allows standby current to flow through 603 pin 1 and pin 2 D631 0658 C E The output of 603 4 outputs sink current from 1 9 FB As a result 601 6 responds accordingly to adjust the duty cycle and frequency output applied to Q602 in order to produce the reduced unregulated output voltages 601 6 PWM Q602 Drain T601 R631 5 FEED Back C628 OUT jce01 SWITCHING
13. necessary Clamping and Blanking signals required from the Timing and Sync parameters of the video input IC001 outputs the R G B signals at pin 20 R OUT pin 24 G OUT and pin 27 B OUT CN309 1 C BLK CN309 3 CLP 39 RGB OUT The RGB outputs from 001 are applied to RGB OUT 002 pin 8 R IN pin 9 IN and pin 11 B IN 002 provides the final amplifier stage for the RGB video signals The output of IC002 pin 1 B OUT pin 3 G OUT and pin 5 R OUT drive the CRT cathodes via AC coupling The output drive levels are approximately 45V p p IC001 20 OUT 002 5 OUT ROZO CN309 C SYNC6O 4IC_ SYNC CLAMP 2 v BPCLP 001 BLK 8 C_BLK RGB DRIVE MAT G OUT SDA 1 8IICSDA R OUT B OUT SCL 2 6 5 RO20 CN306 R317 STBY Y 12V axe O A QOO gt 7 B IN B ABL C370 FROM 9 G IN GND 008 lt R218 C230 0 SYNC IN ep GBKG R118 C130 RBKG 80V R311 R309 TO N BOARD CN1004 TO N BOARD CN1003 4001 56001 V SOCKET 1 7 19 H1 r D305 C306 L301 LN R211 D204 C206 0205 X 1047 R209 RGB OUT LM2405 G OUT JG V R109 BOARD L201 VCC BIAS 1 eI e 8 5 R251 101 151 C106 D105 0306 V M D106 12V 004 CUT OFF GIN AMP 56101 V 56002 E 1 2kV FROM D BD 510 TO SENSING CIRCUIT RGB DRIVE OUT 40 RUS984 1126 4 1
14. user with feedback as to the Power Saving and Failure condition of the monitor H V SYNC BOARD VIDEO H V DEF HV CONV POWER BLOCK D BOARD CONVERGENCE 1001 CONVERGENCE MICRO ALIGNMENT JIG POWER FACTORY SERVICE SAVE DDC PC HOST COMPUTER D BOARD KEY INPUTS H V DEF BOARD DEFLECTION BLOCK CONVERGENCE FOCUS USER CONT USER CONTROLS D BOARD POWER EEPROM OVERALL BLOCK RUS981 1070 3 24 99 Power Supply The Power Supply which is located on the D Board operates very similar to previous monitor chassis design such as the D1 chassis This unit incorporates the use of a switch mode power supply It has both PWM and RCC characteristics The Power Supply has four modes of opera tion Except for the AC power switch three modes are controlled by 1001 Board The modes of operation are Off Active Off Sus pend Standby and Active On These modes are related to the Power Saving and Self Diagnosis functions The Power supply provides all the necessary operating voltages along with Horizontal Centering and CRT Heater voltages Deflection The Horizontal and Vertical deflection circuits along with Horizontal Cen tering Size Rotation and Tilt are located on the D Board The N Board provides these circuits with the necessary size position and geometry parameters as required by the different video timing
15. 000 10 6 INPUT 15 11 0011 7 EEPROM 24LC21AT DDC RUS9811 1069 4 1 99 56 DDC Data Format EDID Basic EDID consist of 128 bytes Number Description 8 Bytes Header 10 Bytes Vendor Product Identification 2 Bytes EDID Version Revision 5 Bytes Basic Display Parameters Features 10 Bytes Color Characteristics 3 Bytes Established Timings 16 Bytes Standard Timings 72 Bytes Detailed Timing Description 1 Byte Extension Flag 1 Byte Checksum 57 5 58 Horizontal Deflection Overview The Micro 1001 and DSP IC 1002 Board respond to the Timing and Sync parameters of the video inputs and provide the necessary Horizon tal Drive and Geometric correction waveforms for the Horizontal Deflec tion circuit on the D Board Horizontal Deflection and High Voltage is controlled by IC805 HV H SIZE REG CTRL 16805 produces PWM Pulse Width Modulation drive outputs to control for Size Bow Pincush ion and Keystone Control for linearity centering and impedance match ing are also part of the Horizontal Deflection circuit Horizontal Drive IC 1002 N Board outputs Horizontal Drive on 25 H OUT via CN101 26 to CN801 26 HD OUT on the D Board The HD OUT signal is applied to Q501 H Drive buffer Q501 shapes amplifies and inverts the HD OUT signal and is applied to Q502 and Q503 Push Pull H Drive buffer Q50
16. 01 then outputs 9V DC to provide power to 605 1 INPUT1 Finally at the same time 605 7 OUTPUT 1 outputs regu lated 5V DC During normal operation the 8V DC supply is used to provide VCC volt age to 605 1 The Back up supply circuit 0601 is shut down via the REMOTE ON OFF command from 1 1001 7 Troubleshooting 5V Standby Circuit The loss of the 5V DC Standby voltage may appear as a no power symptom Check the 16V DC source R617 0601 0606 0607 605 and related components Check the 8V DC source D654 R654 and D610 31 12V Regulator During Active Off and Suspend Standby modes the 16V DC supply is reduced to 9V DC and is applied to 605 2 INPUT2 The REMOTE ON OFF control signal from IC1001 7 is L and is routed to 605 3 DIS ABLE which disables the 12 DC regulated output During Active On modes the 16V DC supply is applied to 605 2 IN PUT2 The REMOTE ON OFF control signal from IC1001 7 is 5V and is routed to IC605 3 DISABLE to enable the 12V DC output at pin 6 OUTPUT2 Troubleshooting 12 Regulator During the Active On mode confirm the presence of 12V DC at IC605 6 OUTPUT2 If missing verify that a H is present at IC605 3 DIS ABLE 605 5V 12V REG TDA8 138A INPUT 1 INPUT 2 Q601 5V BACK UP STANDBY SUSPEND lt gt STANDBY SUSPEND GND OUTPUT 1 DISAB
17. 2 and Q503 amplify the HD OUT signal and is applied to Q504 H Drive The 16V DC supply is applied to Q504 S and the Drain of Q504 is at OV DC via T501 to ground Q504 drives T501 HDT Horizontal Drive Trans former which provides base current to Q505 H OUT 0505 collector produces approximately 1kV P P spike to drive the positive side of the Horizontal Deflection Yoke H DY through T504 HST Horizontal Size Transformer The negative side of the Horizontal Deflection Yoke H DY is AC coupled to ground via L502 HLC Horizontal Linearity Coil T503 LCT Linearity Coil Transformer L505 R522 and C513 59 CN801 26 HD OUT Q505 C 805 PWM FROI H SHAPE HD 1002 64 O N BOARD CN801 H SHAPE 27 12V R813 1801 12 12 C820 C804 R503 502 R501 R502 OS 0501 540 R537 gt HD OUT Pe FROM HD OUT 1002 25 BOARD DEFLECTION CIRCUIT 60 C507 1 6541 4 1 R540 S CAPS amp 0507 CONTROL 1002 27 IC1001 32 RUS9813 1098 3 15 99 61 Horizontal AFC The horizontal output pulse of Q505 H OUT is coupled to Q514 H RTRC and buffered The horizontal pulse H FBP via CN801 32 to CN1001 2 N Board is input to IC 1002 27 FBP IN 1002 utilizes the FBP to phase lock the HD OUT signal at pin 25 HD OUT CN801 32 H FBP 1504 H DY REMOTE 9306 ON OFF L PWMNO T902 P4 0 0505 i IC1001
18. 4 O N BOARD CN801 H SHAPE 27 12V R813 1801 12 12 C820 C804 R503 502 R501 R502 OS 0501 540 R537 gt HD OUT Pe FROM HD OUT 1002 25 BOARD DEFLECTION CIRCUIT 64 C507 1 6541 4 1 R540 S CAPS amp 0507 CONTROL 1002 27 IC1001 32 RUS9813 1098 3 15 99 65 Pin Keystone Bow and Geometric Corrections The DSP 1002 Board 64 E W output is also used for Pin Keystone Bow and Geometric corrections 1002 alters the parabola waveform H SHAPE that is input to 805 2 1805 20 outputs the nec essary PWM drive to Q506 H SIZE REG OUT to control the amount of B that is applied to Q505 H OUT By adjusting the amount of B the circuit can correct for Pin Keystone and Bow IC805 2 H SHAPE IC805 20 PWM 805 PWM FROI H SHAPE HD 1002 64 O N BOARD CN801 H SHAPE 27 12V R813 1801 12 12 C820 C804 R503 502 R501 R502 OS 0501 540 R537 gt HD OUT Pe FROM HD OUT 1002 25 BOARD DEFLECTION CIRCUIT 66 C507 1 6541 4 1 R540 S CAPS amp 0507 CONTROL 1002 27 IC1001 32 RUS9813 1098 3 15 99 Horizontal Centering Raster only The Micro 1001 Board controls the Raster position via the Horizon tal Centering circuit comprised of Q517 Q515 and 502 H C
19. 56101 V 56002 E 1 2kV FROM D BD 510 TO SENSING CIRCUIT RGB DRIVE OUT 42 RUS984 1126 4 1 99 On Screen Display OSD 003 OSD is the On Screen Display character and graphic generator 1001 Board via the data bus controls 003 at pin 3 SDA and 4 SCL Board also provides 003 5 HSYNC 6 VSYNC and pin 7 HFLY with the necessary sync timing signals 003 provides OSD G B and Fast Blanking to RGB DRIVE 1 001 for mixing the OSD with the main video signal The OSD GB signal is output from IC003 pin 14 ROUT pin 15 GOUT and pin 16 BOUT and is input to IC001 pin 13 B OSD pin 14 G OSD and pin 15 R OSD The Fast Blanking signal is output from 1003 17 FBLK and is input to 7 OSD BLK which blanks the area where the OSD is to be displayed 001 17 OSD BLK The 12V DC supply from the D Board is input to 009 1 901 3 out puts regulated 5V DC to 003 pin 9 and 19 providing VCC operating voltage 43 ASC Auto Size and Center The ASC function automatically adjusts for proper size and centering of the video image on the screen This is provided by 003 OSD HSYNC V SYNC and HRTRC signals from the Board are input to IC003 pin 5 HSYNC pin 6 VSYNC and pin 7 HFLY When the ASC function is selected 001 16 V DET outputs composite blanking to 003 8 AV This signal is processed by 003 which
20. 5V Pin 53 H L to switch the respective S CAP into the circuit 28 Q510 5 ov Pin S4 H H 47 509 5V 5V Note With No Video Input the H freq Is 69 696kHz and the S Cap logic Pin S5 H H outputs are all 5V 46 Q508 45V SV N Board H Fre 69 696 kHz 31 496 kHz Resolution Dots x Lines Switching 640 480 800 600 1024 768 1152 864 1280 1024 1600 1200 L H o d amp OS 0513 5V 5V 5V 5V 0V 5V H H H S1 H L 5V 0V 5V OV 5V L L L V V 0V 0V 0 OV OV OV H Freq 43 284 kHz 53 545 kHz 68 740 kHz 67 523 kHz 90 894 kHz 74 268 kHz Picture resolutions were generated using Windows 95 Display Properties for the CPD 420GS H DEFLECTION CIRCUIT 9505 C525 gt ee 529 R527 CN801 S S S 5 5 0 1 2 5 4 5 5 R1047 1049 R1051 R1048 R1050 N BOARD 6 69 9 49 27 49 P3 0 1 P8 0 P3 1 P3 2 P3 3 IC1001 MICRO S CAPS RUS9814 1108 4 1 99 72 Horizontal Deflection Shutdown Protection The horizontal output pulse of Q505 H OUT is coupled to Q514 H RTRC and buffered The buffered horizontal pulses H FBP via CN801 32 to CN1001 2 Board is input to 1 1002 27 FBP IN 1002 utilizes the H FBP to phase lock the HD OUT signal at pin 25 HD OUT The H FBP signal is also input to 1 1001 32 1001 monitors the H FBP pulses and if the pulses
21. 9 ABL Shutdown ABL Shutdown is activated when CRT beam current becomes excessive T901 11 FBT output is rectified by D904 and filtered by C929 As beam current increases the voltage output from T901 11 decreases current is inversely proportional to the voltage In extreme cases when beam cur rent becomes excessive and the output voltage from T901 11 decreases to OV 1001 7 REMOTE ON OFF responds by going L OV and as a result the power supply enters the Active Off mode NOTE If Beam current ABL becomes excessive LED illuminates Or ange 0 5 seconds Off 1 5 seconds SUPPLY 1001 5 TO VDF 0904 4 D BOARD HV ABL PROTECTION RUS9824 1123 3 15 99 80 Dynamic Focus DF Circuit Overview Two separate Dynamic Focus circuits Horizontal and Vertical are incor porated to provide an increase in the overall sharpness of the picture especially in the corners of the CRT Each of these circuits provide their own respective correction waveform Previous chassis designs used a single correction waveform to create Dynamic Focus control Horizontal DF The Horizontal Dynamic Focus circuit is comprised of circuit elements 1C703 H DF OUT and T701 DFT 1 1002 DSP Board pin 10 HDF 1 outputs the H DF correction waveform and is input to 703 4 IN The output of 703 6 OUT A drives the primary of T701 DFT 1 secondary s
22. 983 1125 3 25 99 Convergence Circuits Overview The Static Convergence adjustments can be performed by the DAS Soft ware or the user OSD menu The Dynamic Convergence adjustments can only be performed using the DAS Software The DSP 1 1002 Board provides the Static Convergence 704 5 CONV OUT and the Dynamic Convergence 701 D CONV OUT with the complex two di mensional convergence waveforms and DC bias The Static Conver gence circuit provides correction for the G B beam landing in the center areas of the CRT And the Dynamic Convergence circuit provides correc tion for the B beam landing in the outer areas of the CRT via a separate convergence yoke on the CRT Static Convergence 704 The DSP 1 1002 60 YSC outputs the complex convergence waveform and is routed to the D Board The YSC signal is input to 704 7 INB 1C704 current amplifies the YSC signal and the output at pin 9 IOUTB is applied to the convergence yoke When the Static Convergence adjust ment is performed IC1002 varies the DC reference level of the YSC sig nal positive or negative The YSC signal is applied to the convergence yoke to shift the R and B beam landing in the horizontal direction 1C704 7 YSC 93 The DSP 1 1002 61 XSC outputs the complex convergence waveform and is routed to the D Board The XSC signal is input to 704 3 INA 1C704 current amplifies the XSC signal and the output at pin 1 IOUTA is applied
23. B outputs When Contrast is adjusted 001 varies the plitude of the RGB outputs 001 outputs the RGB signal at pin 20 OUT pin 24 G OUT and 27 B OUT IC001 20 OUT ROZO CN309 C SYNC6O 4IC_ SYNC CLAMP 2 v BPCLP 001 BLK 8 C_BLK RGB DRIVE MAT G OUT SDA 1 8IICSDA R OUT B OUT SCL 2 6 5 RO20 CN306 R317 STBY Y 12V axe O A QOO gt 7 B IN B ABL C370 FROM 9 G IN GND 008 lt R218 C230 0 SYNC IN ep GBKG R118 C130 RBKG 80V R311 R309 TO N BOARD CN1004 TO N BOARD CN1003 4001 56001 V SOCKET 1 7 19 H1 r D305 C306 L301 LN R211 D204 C206 0205 X 1047 R209 RGB OUT LM2405 G OUT JG V R109 BOARD L201 VCC BIAS 1 eI e 8 5 R251 101 151 C106 D105 0306 V M D106 12V 004 CUT OFF GIN AMP 56101 V 56002 E 1 2kV FROM D BD 510 TO SENSING CIRCUIT RGB DRIVE OUT 46 RUS984 1126 4 1 99 G2 control and Spot Killer The G2 source voltage from the D board enters the A board via CN301 1 via R048 and R064 The node between R048 and R064 is connected to the CUTOFF CTRL circuit comprised of IC005 and 0001 The G2 adjust ment can only be performed using the DAS CATS Software or the Color Restoration function explained later The Micro 1001 Board the bus instructs 001 to v
24. ENT OUT The Horizontal Centering Raster only can only be adjusted using the DAS Software 1001 outputs Horizontal Centering voltage on 4 CN1001 30 to CN801 30 on the D Board The H CENT volt age is applied to Q517 buffer and is then applied to Q515 H CTR CTRL Q515 inverts and amplifies the H CENT voltage and is input to 1502 2 When Horizontal Centering is adjusted the voltage input to 502 2 varies and as a result the output of 502 4 also varies The output of 1502 4 via R541 R546 and L503 applies a positive or negative DC offset to the Drain of Q506 H SIZE REG OUT This DC offset moves the Raster position left or right of center Q802 and Q516 are controlled by the REMOTE ON OFF command to mute the input to IC502 during power save 67 Caution 502 is powered by a floating supply Do not attempt to check voltages at IC502 with an O Scope by attaching a ground lead to 77 floating ground This may result in damage to IC502 Use a DVM when verifying voltages around 502 16502 CONT N BOARD IC1001 REMOTE ON OFF D BOARD H CENTERING CIRCUIT RUS9826 1135 4 1 99 68 Horizontal Linearity The Micro IC1001 2 Board outputs Horizontal Linearity control via CN1001 28 to CN801 28 H LIN BAL on the D Board The Horizontal Linearity circuit is comprised of L502 HLC Horizontal Linearity Coil T503 LCT Linearity Coil Transforme
25. H V DEF HV CONV POWER BLOCK CONVERGENCE FOCUS RUS981 1070 3 24 99 Power Supply Overview The power supply in this unit is a switch mode power supply The power supply is rated to operate with an AC input voltage range of 100V 240V Current input is 1 2 1 7 A The output of the power supply produces 180V 80V 16V 12V and 5V DC from the AC input In addition it provides 6 3V DC for the CRT Heater and an isolated 8V DC output to the Horizontal Centering circuits It has a fold back mode used for the Power Saving and Failure Shutdown operations This chassis incorpo rates the use of a single power supply control 601 601 provides most of the power supply control except for output power switching pro vided by Q602 POWER SWITCH AC Input AC input section provides EMI filtering input protection surge limit ing and CRT degauss operation AC Input Troubleshooting For No Power or Dead Set condition the AC Input circuitry should be checked F601 should be checked for continuity CN603 to the Board and the AC power switch S601 should be checked for continuity Further checks should be made to R602 TH600 and D601 respectively if no prob lems can be identified EMI Filter The EMI filter comprises X capacitors C601 and C602 Y capacitors C603 C604 C605 and C606 and the line filter transformer LF602 Input protection is provided by F601 and surge current limiting by thermistor TH600 and res
26. IN 701 current amplifies the XDC signal and the output at pin 6 OUT A is applied to the convergence yoke When the Dynamic Convergence ad justment is performed 1002 varies the DC reference level shape and size of the XDC signal The XDC signal is applied to the convergence yoke to shift the R and B beam landing in the vertical direction in the outer areas of the CRT 95 701 6 XDC The DSP IC1002 7 DCC output is routed to the D Board to provide 701 3 IN B and pin 4 IN A with a DC bias voltage offset REF DC The Micro 1 1001 7 REMOTE ON OFF output is routed to the D Board and is input to IC701 11 STBY to mute the outputs of IC701 when in the Active Off and Standby Suspend modes OUT B Y IN N I N B Y B Y X A X IC701 D CONV OUT UT x VEE sTBY CN1001 CN801 REMOTE 6 CONVERGENCE YOKE R705 R706 R704 R710 AA R712 D BOARD DYNAMIC CONVERGENCE 96 a IC1001 MICRO PWM 6 0 SDA N BOARD RUS9820 1120 3 25 99
27. LE OUTPUT 2 REMOTE ON OFF FROM N BOARD 1001 7 STANDBY HEATER 32 604 HEATER OQ our 6 BD lt 3 2V gt ON OFF FROM N BOARD 1001 8 RUS985 1076 3 25 99 Heater Voltage Regulator Heater filament voltage is developed by the 8V DC supply to IC604 1 1 During Active On mode IC 1001 8 Board outputs the HEATER con trol line H 5V which is routed to 604 4 VC to enable the 6 3V DC Heater supply voltage output at pin 2 During Standby Suspend mode the power supply is operated at reduced voltages As a result the input voltage to 1 604 4 VC is 5 5V DC The output from IC604 2 is also reduced to 3 2V DC keeping the heaters of the CRT active on during the power saving function This allows the CRT to quickly display the information or video during the Standby Suspend to Active On transition During Active Off mode 1 1001 8 Board outputs a L OV to IC604 4 VC disabling the 6 3V DC Heater supply voltage 33 Troubleshooting Heater Voltage A loss of Heater Voltage will result in a no picture condition During Active On mode confirm 1 1001 8 Board outputs HEATER control line 45V to IC604 4 VC to enable the 6 3V DC Heater supply voltage Also check for shorts or an open on the A Board and the CRT 605 5V 12V REG TDA8 138A INPUT 1 INPUT 2 Q601 5V BACK U
28. P STANDBY SUSPEND lt gt STANDBY SUSPEND GND OUTPUT 1 DISABLE OUTPUT 2 REMOTE ON OFF FROM N BOARD 1001 7 STANDBY HEATER 34 604 HEATER OQ our 6 BD lt 3 2V gt ON OFF FROM N BOARD 1001 8 RUS985 1076 3 25 99 Micro Standby and Reset Board 5V DC Standby supply from 605 D Board is routed to 1001 pin 11 and pin 31 providing VCC operating voltage The 5V DC standby supply is also applied to the RESET 1003 1 1003 produces a Re set pulse at pin 3 when the unit is first turned ON The 8Mhz master clock is developed by 1001 1001 44 pin 45 When the unit is first powered ON the Degauss command line of IC1001 5 goes H 5V for approximately 5 seconds then returns to a logic L OV At the same time the REMOTE ON OFF command from IC 1001 7 goes H 5V This signal is routed to the D Board via CN801 16 to enable the Active On mode of the power supply 35 DSP Regulator The DSP IC 1002 requires 3 3V DC for proper operating 1006 3 outputs regulated 3 3V DC to 1002 pins 9 12 28 and 52 1003 provides IC 1002 54 RESET with a delayed RESET H 5V via R1105 The DSP outputs Deflection Drive Convergence and Geometry Correc tion Waveforms to their respective circuits located on the D board NOTE Wit
29. R641 The 80V DC from T601 through R641 is applied to Q640 C Normally the 5V DC from 605 and D641 turns 0640 ON 0657 OFF If there isa substantial short circuit on any of the secondary low voltage supplies the 5V DC standby supply can be attenuated If it goes lower than 3V DC Q640 will turn OFF With Q640 OFF Q657 turns ON to bypass the feedback voltage from 603 This causes 601 to in crease the drive output to the point of OVP latch via pin 7 Troubleshooting Short Circuit Protection The power supply can be operated in the Active Off mode to better trouble shoot each circuit under reduced voltages by simply disabling the RE MOTE ON OFF line from the Board by lifting 16 of CN801 0640 and Q657 should be check respectively 6 ON OFF 180V 8V POWER SHUTDOWN N BOARD R631 5 1001 6 FEED BACK 80V Q657 V D640 4 R641 1 OCP Ya C607 R643 FAULT Q640 PROTECT se42 SHORT CIRCUIT qA PROTECTION SA C640 N 3 5V Ape wr 180V R659 C613 C627 ACTIVE OFF Rees 2 R668 R660 OCP ENABLE CONTROL rus9815 1131 PROTECTION SHUT DOWN 28 4199 29 Troubleshooting Secondary Circuits Troubleshooting Horizontal Centering Failures in these sections are interrelated and one circuit can affect A loss of the Horizontal Centering adjustment can be caused by the fail another Consequently some failures will also affect the primar
30. S O NY Training Manual CPD 420GS D98 Chassis Computer Monitor Circuit Description and Troubleshooting Course MON 03 098 Chassis Specifications Power Saving Function Self Diagnosis Function Timing Specification for CPD 420GS Troubleshooting Safety Overall Block N Board A Board H Board D Board Power Supply AC Input AC Input Troubleshooting EMI Filter Degauss Circuit Degauss Troubleshooting Start Up and Active On Operation Regulation Secondary Voltages Active Off and Suspend Standby Operation Secondary Voltages Power Supply Protection Circuits Table of Contents o o o ON QI In 13 15 17 19 21 OVP Over Voltage Protection UVP Under Voltage Protection OCP Over Current Protection Troubleshooting Protection Circuits No Power Troubleshooting Feedback Circuit Troubleshooting The AN8037 Power supply Controller Troubleshooting Short Circuit Protection Troubleshooting Secondary Circuits Rectifier Section Troubleshooting Troubleshooting Horizontal Centering 5V Standby Circuit Troubleshooting 5V Standby Circuit 12V Regulator Troubleshooting 12V Regulator Heater Voltage Regulator Troubleshooting Heater Voltage N Board Micro Standby and Reset N Board DSP Regulator Video and OSD Processing RGB Preamp 21 21 21 21 23 23 25 27 29 29 29 31 31 31 31 33 33 35 35 35 37 37 RGB Drive RGB OUT RGB CUTOFF On Screen Displa
31. Video image area Resolution 0 25 0 27 mm aperture grill pitch 19 inches measured diagonally 90 degree deflection Trinitron 18 maximum viewing image Approx 365 x 274 mm w h 14 3 8 x 10 7 8 inches Horizontal Max 1600 dots Vertical Max 1200 lines Standard image area Approx 352 x 264 mm w h Input Signal Video Sync 13 7 8 x 10 1 2 inches Analog RGB 75 ohms typical 0 7 V p p Positive External HD VD Composite Polarity Free TTL Video Composite Sync on Green 0 3 V p p Negative Power Consumption Maximum Nominal Deflection frequency AC input voltage current Dimensions Mass Plug and Play 130W 100W Horizontal 30 to 96 kHz Vertical 48 to 120 Hz 100 to 120V 50 60 Hz 1 7A 220 to 240V 50 60 Hz 1 2 444 x 467 x 455 w h d 17 1 2 x 18 1 2 x 18 inches Approx 26 kg 57 Ib 5 oz DDC DDC2B Front Rear input DDC2Bi Rear input only Design and specifications are subject to change without notice POWER SAVING FUNCTION The monitor has three Power Saving modes By sensing the absence of a video signal from the computer it reduces power consumption as fol NOTE If video signal is input to the monitor the NO INPUT SIGNAL message appears After about 30 seconds the Power Saving function automatically puts the monitor into active off mode and the indicator lights up orange Once the monitor detects horizontal and vertical sync signals
32. and D801 is input to 805 13 REF When beam current be comes excessive and the output voltage from T901 11 decreases the reference voltage at IC805 pin 13 and pin 14 is decreased As a result the duty cycle of the PWM output from 805 18 is reduced and the HV output is decreased to limit beam current and prevent CRT damage 805 18 PWM 77 0502 Q503 HD OUT uDC5021 end 2 R809 R911 V C8347 8011 0802 4 FROM 1901 11 ABL CN510 A BOARD HV DET CN801 R811 24 2 0908 Dl 0902 FB90 HV OUT 32 P 6 4 L902 C924 TO G2 1kV C933 300V HV 78 HV FEEDBACK C829 T901 ANODE OF CRT WW R902 3 56901 20926 4 C927 1 CRT VIA RED FV LEAD R908 R909 OQ R923 SG902 gt Y 50905 R914 D909 CRT VIA BLK FV LEAD OOO RUS9819 1118 3 15 99 Protection Shutdown High Voltage protection is performed by monitoring the 300 DC output source from T901 8 FBT via R917 and rectifier D905 The 300 DC source is voltage divided by R921 and R922 When the HV rises above the threshold of D908 the HV DET line of 1C1001 16 will rises above 5V DC This results in IC1001 7 REMOTE ON OFF to go L OV causing the power supply to enter the Active mode NOTE If HV becomes excessive LED illuminates Orange 0 5 seconds Off 0 5 seconds 7
33. are missing IC1001 7 REMOTE ON OFF goes L to set the power supply in the Active mode CN801 32 H FBP 73 NOTE LED illuminates Orange 1 5 seconds Off 0 5 seconds REMOTE ON OFF PWMNO P40 jc1oo1 MICRO P5 0 HFBACK HORIZONTAL PROTECTION AFC RUS9B25 1124 3 15 99 74 High Voltage Circuit Overview The HV High Voltage circuit is comprised of circuit elements IC805 HV H SIZE REG CTRL Q901 HV REG OUT Q902 HV OUT and T901 FBT These circuits develop regulated CRT Anode voltage G2 Screen voltage and Focus voltage In addition there are High Voltage and Beam Current protection circuits High Voltage IC805 HV H SIZE REG CTRL utilizes the HD OUT input signal at pin 8 to produce the proper HV Drive PWM output frequency at pin 19 The HV Drive PWM is applied to Q902 HV OUT which produces approxi mately 700V P P pulses and drives the input of T901 FBT The second ary of T901 internally rectifies the pulses and generates the necessary HV for the CRT Anode 805 19 PWM 75 High Voltage Regulation A sample of the HV produced by T901 is output at pin 17 This voltage is divided by R810 R902 R903 R906 R907 R923 and RV904 and input to 805 12 This sampled feedback voltage is mixed with the internal triangle OSC and output as PWM drive at pin 18 The PWM correction drive output is applied to Q901 HV REG OUT which controls the amount of
34. ary the DC level of pin 6 G2 This volt age is routed to the non inverting input of IC005 5 CUTOFF CTRL The DC output from pin 7 OUT is input to Q001 E and output at Q001 C configured as a common base amplifier Q001 C is connected to the node between R048 and R064 By varying the DC voltage at this node the DC level at J001 10 G2 of the CRT can be adjusted C028 provides bias to Spot Killer Q001 B during power OFF reducing the G2 voltage to minimum 47 OUT67 ABL BOARD 1 50 GND GND GND CN1003 RGB DRIVE SCL 5 R G B v B G OUTRO BKG G2 DET 050 050 OSD 002 IC003 8 D BOARD CN510 IC005 CUT OFF CONTROL uPC455862 co28 SPOT i KILLER R049 RO46 2565022 R047 0020 77 G2 AND SPOT KILLER RUS9810 1068 4 1 99 48 Color Restoration OVERVIEW The Color Restoration function can be performed by the user to restore the White Balance of the CRT The CRT beam current is measured when White Balance is performed via the DAS CATS software The CRT beam current is converted to a voltage and stored in registers During the Color Restoration function these registers are sampled and the CRT beam current is adjusted until they equal the values stored in the registers The Color restoration function can only be accessed via the OSD menu and activated after an initial warm up period of approximately 30 minute
35. conditions and user adjustments Impedance matching S Caps and Horizontal Linearity are also performed in the Horizontal deflection circuit as required by the dif ferent video timing conditions Convergence Both Static and Dynamic Convergence circuits are located on the D Board The N Board provides these circuits with the necessary geometry param eters as required by the different video timing conditions and user adjust ments The convergence circuits provide two dimensional H and V cor rection patterns that are applied to the convergence yoke High Voltage The HV generation and regulation circuits are located on the D Board The N Board provides the HV circuits with the necessary drive param eters required by the different video timing conditions The HV circuit provides the CRT with Anode Focus and Screen voltages required for proper CRT operation The D98 chassis is also equipped with Dynamic Focus circuitry located on the D Board The Dynamic Focus circuit controlled by the N Board provides the necessary focus control voltage for the outer edge areas of the screen as required by the different video timing conditions 5 BOARD VIDEO DEF HV CONV POWER BLOCK D BOARD CONVERGENCE CONVERGENCE ALIGNMENT JIG POWER FACTORY SERVICE SAVE DDC PC HOST COMPUTER KEY INPUTS BOARD USER CONT USER CONTROLS D BOARD POWER OVERALL BLOCK D BOARD
36. dition Under Voltage occurs when the input at pin 7 VCC is less than 9 5V DC Once this threshold is reached IC601 will latch and disable the output at pin 6 OUT going to Q602 resulting in power supply shut down Once 601 is latched you must turn the AC power OFF and ON again to restart the power supply 21 OCP Over Current Protection OCP is activated if there is excessive current passing through Q602 POWER SWITCH R609 is used for current sensing Current through R609 will cause a negative voltage drop in reference to HOT ground R608 R606 and C615 couples this voltage drop to 1 601 4 CLM Should this voltage level exceeds 0 18V IC601 will enter the cycle by cycle cur rent limiting mode To prevent premature OCP sensing Q605 and IC606 provide a Soft Start to 601 2 CCP to prevent OCP during start up Troubleshooting Protection Circuits Each protection circuit can be isolated to their respective defect The power supply can be operated in the Active Off mode to better trouble shoot each circuit under reduced voltage condition by simply removing the N Board 1601 SRT SWITCHING TRANSFORMER OUT GND CFI CCP TR 7 606 IC601 POWER SUPPY CONTROL CONTROL AN8037 vC IC603 4 START UP PROTECTION 22 Q605 REMOTE ON OFF N BOARD 1C1001 7 RUS9831 1140 4 1 99 No Power Troubleshooting 601 Troubleshooting First apply AC to the monitor and chec
37. down Heaters Remote On Off and 5 Caps Im pedance Matching 1001 controls the Power Save Function OSD On Screen Display and RGB DRIVE A board 1001 also provides com munication with DAS Digital Alignment Software CATS Color Adjust ment Tool for Service and the DDC Display Data Channel 1002 outputs Deflection Drive Convergence and Geometry Correction Waveforms to their respective circuits located on the D board A Board The main function of the A Board is to receive incoming video signals and process them into RGB video drives for the CRT Video signals can be received either from the conventional 15 D sub connector or via an addi tional 15 D sub female connector input located on the front of the monitor The purpose of this second input is to allow easy hookup to a laptop computer video cable provided The A Board circuitry buffers the Sync timing signals and provides OSD video The Timing Analysis for the ASC Auto Size Center function and the Analog to Digital conversion for the Color Restoration function are also processed Additional functions include the DDC information to the DDC equipped host computer and all CRT cathode operating voltages such as Heater G2 Screen and Focus are either processed or passed to the CRT H Board The User controls are located on the front bezel assembly of the monitor and provide the user with control of various monitor operations and func tions The LED provides the
38. e DDC2B communication channel is based on the protocol host graphics card can request EDID or VDIF Video Information infor mation over the DDC2B channel Not only is DDC2B faster it allows the operating system to query the monitor for supported features and inform you of any configuration changes For your monitor to be fully Plug and Play compatible it must have both DDC1 and DDC2B capabilities With a Plug and Play video adapter you are able to change resolutions and colors without having to restart your computer Designers are developing innovations to keep pace with Plug and Play such as a communication cable that plugs into a port similar to a tele phone jack on the monitor With the introduction of the ACCESS bus or DDC2AB compatibility include DDC2B bi directional communication and to add connectivity between many devices ACCESS bus peripherals can be daisy chained in any order so that everything plugs into one port on the back of your computer system Since the ACCESS bus conveys information directly to your system mice and keyboards as well as other compatible components can be plugged and unplugged without having to restart your computer Especially useful for monitors the ACCESS bus allows you to adjust your screens image using a mouse and keyboard This not only eliminates the need to push buttons on the display it allows you to store monitor settings under mean ingful names that are easily recalled The n
39. elops all the sec ondary operating voltages After start up the output from T601 8 through R623 is rectified by D605 and provides VCC 17V DC through D624 and 0657 to 601 7 during normal Active On operation Q602 Drain 1601 SRT SWITCHING Q602 POWER SW IRF1B44 LCLF65 C619 R615 FB 50 OUT GND CCP TR VCC CLH IC601 POWER SUPPY CONTROL AN8037 START UP 12 TRANSFORMER CY D654 R474 D655 c618 T gt oo PI C654 D652 652 gt 5 FBe01 56527 651 0651 651 FB604 _peso 77 C650 R622 CAN 16V 5 0 1 bd 16 2 80V 180V 2 180V L650 R650 K H D649 657 R621 C656 EANA H Dene 16548 REMOTE ON OFF N BOARD 1C1001 7 OCP ENABLE CONTROL IC603 4 RUS98 6 1066 5 24 99 Regulation Overall regulation is accomplished by varying the feedback voltage to 601 9 FB The secondary 16V DC supply via R631 D614 and R658 provide 603 1 with a reference voltage The secondary 180V DC sup ply is voltage divided by R659 R663 and R660 to provide 652 1 ER ROR AMP with a sample of the 180V DC supply 1001 7 Board REMOTE ON OFF command is set 5V which turns Q656 and turns 0658 OFF this allows 652 3 to control feed back 652 is a shunt regulator and controls the current through IC603 1 pin 2 Any change in the B voltage will cause 652 pin 3 to vary in voltage in
40. ewest standard USB Universal Serial Bus includes all the capa bilities of ACCESS bus but transmits and receives data at a much faster rate Instead of 400K sec USB will be able to communicate at an incred ibly fast 12MB of data per second which makes it ideal for digital video and telephony Because of its transmission capabilities USB is expected to win over the current ACCESS bus standard and will be the one to watch as Plug and Play continues to mature 54 Display Data Channel Circuit DDC1 The front input supports DDC1 communications The front input cable pin 12 SDA and pin 15 SCL are connected to CN312 pin 1 DDCSCL and pin 2 DDCSDA on the A Board 1C007 EEPROM pin 5 SDA and pin 6 SCL provides the host with DDC1 communication The V Sync input to 007 7 VCLK is used to synchronize the timing of the data reading cycle 007 7 55 DDC2B DDC2AB The rear input supports DDC2B and DDC2AB communications The rear input cable pin 12 SDA and pin 15 SCL are connected to CN310 pin 2 DDCSCL and pin 3 DDCSDA on the A Board The data is passed through the A Board to CN311 pin 2 DDCSCL and pin 3 DDCSDA CN311 is connected to the Board via connector CN1003 pin 2 DDCCLK and 3 DDCDATA and are input to 1001 pin 34 DDCCLK and pin 35 DDCDATA CN311 3 DDCSDA 1 5 DDCCLK 2 6 09000 10 REAR DDCCLK 2 INPUT DDCDATAI3 11 15 IC1001 MICRO 5 1 00
41. h AC power applied the output waveforms from the Micro and DSP should always be present 605 5V 45V 12V REG N BOARD TDA8138A IC1006 GND OUTPUT 1 5V 5V 2 INPUT 1 INPUT 2 DISABLE oUTPUT 2 5V REG R1039 L1001 Q601 12V 0610 5V BACK UP C634 R617 gt WD VCC OUT P IC1003 D607 RESET C635 CN801 L CN1001 ae 1 DEGAUSS PJ 670 6 TO lt PWR SHUT DN Q657 HEATER POWER SUPPLY 4 HEATER TO OUT 8V C O G REG 5 T cese 1005 MICRO DSP STANDBY rus9812 1097 4 1 99 36 Video and OSD Processing RGB PREAMP RGB PREAMP 1 008 receives the RGB and Sync signals from two sources One is the conventional 15 D sub connector and the other is the 15 D sub female connector input located on the front of the monitor The purpose of this second input is to allow easy hookup to a laptop com puter The RGB signals from the conventional 15 D Sub connector are input to 008 2 pin 5 G and pin 7 The Sync signals are input to 008 8 and 9 The RGB signals from the additional 15 D Sub female connector in put to 008 11 13 G and pin 16 The Horizontal and Vertical Sync signals are input to 008 17 and
42. he Standard Mode upon power on and power save modes 51 Presentation Mode When the Presentation Mode is selected IC1001 Board via the data bus communicates with IC001 RGB DRIVE 001 increases the P P levels approximately 200mV 5 of the RGB output signal at pin 20 OUT pin 24 G OUT and pin 27 B OUT In addition 001 de creases the G and BKG DC level approximately 100mV Graphic Video Mode When the Graphic Video Mode is selected 1001 Board via the data bus communicates with IC001 RGB DRIVE 001 increases the P P levels and via internal detail amp increases the high frequency re sponse of the R G B output signal at pin 20 R OUT pin 24 G OUT and pin 27 B OUT IC001 20 OUT R B SCL SDA Bur 78 IN G 62 9 c IN RGB DRIVE OUT 9 SYNC IN QDR 8 OSD XTAL OUT CSDA ee 6 CSCL FROM H_SYNG BOARD CN1003 HRTRC OSD ASC GPE RUS9823 1122 3 15 99 52 Plug and Play VGA VESA DDC VGA Video Graphics Adapter or Video Graphics Array VESA Video Electronics Standards Association DDC Display Data Channel T At the video card 710 At the monitor cable m D ORO C Cn LT 15 PIN HIGHDENSITY D SUB FEMALE at the video card 15 PIN HIGHDENSITY D SUB MALE at the monitor cable 53
43. istors R602 and R603 Degauss Circuit The Degauss Circuit is used to demagnetize or degauss the CRT During Active On mode the Micro 1C1001 5 Board sets the Degauss signal to digital H 5V The Degauss signal via CN1001 pin 25 to CN801 pin 25 D Board is applied to Q670 DEGAUSS SW Q670 turns ON and activates relay RY601 This allows AC current to flow to the degauss coil through posistor THP602 The current heats up THP602 posistor and its affective resistance increases This dampens the current in the degauss coil to nearly zero allowing the magnetic field to decay gradually After approximately 5 seconds 1001 5 sets the Degauss signal to digital L OV The Degauss signal via CN1001 25 to CN801 25 D Board is ap plied to Q670 DEGAUSS SW Q670 turns OFF and deactivates relay RY601 The degauss coil should sufficiently demagnetize the CRT Degauss Troubleshooting The malfunction of the degauss circuit can be a loss of the degauss signal from the N Board The 5V DC degauss signal can be checked at CN801 25 and should be present for approximately five seconds once AC power is applied The activation of RY601 through Q670 can also be heard Further checks to THP602 and VA601 should be checked respectively Another method of verifying the degauss circuit operation is to use the manual degauss operation found in the OSD menu BOARD
44. k IC601 6 output If the output at pin 6 is not present or briefly appears there could be problems with Q602 and related components Check VCC at IC601 7 If the voltage is less than 9V DC IC601 could be in the latch mode If the voltage is very low R613 R623 D605 D624 and D657 should also be checked respectively If no problems can be identified in reference to Hot ground check the impedance of each pin at IC601 If any of these pins are shorted replace 601 and check components connected to the related pins Take that C616 and C619 are fully discharged before replacing 601 601 6 PWM 23 Q602 Troubleshooting Q602 can be damaged in various ways such as voltage current and tem perature Check Q602 for shorts Further checks to F601 R609 and R615 Additional components to check are D603 D604 and IC601 There is also a clamp circuit which is used to clip the turn off spike found on Q602 D Check D615 C624 and R619 Q602 Drain Feedback Circuit Troubleshooting Problems with the feedback circuits can cause power supply shut down or low voltages First determine whether the power supply is operating in Active Active On modes or not at all The power supply can be stuck in Active mode The Remote ON OFF signal from the Board Q656 Q658 603 and 652 can affect this condition In addition check the protection circuits 1601 SRT SWITCHING TRANSFORMER OUT
45. n adjustments can be made via the user OSD menu and via the DAS Software The Micro 1001 3 Board outputs the ROTATION PWM control waveform and is routed to the D Board The PWM wave form is filtered by R729 and C705 and the DC level is applied to 702 2 702 current amplifies the DC level and the output at pin 4 drives the Rotation Coil via CN702 When the Rotation adjustment is performed the PWM duty cycle changes which results in a change of the DC level applied to IC702 2 The output of 1 702 4 varies from approxi mately 11V DC to 11V DC The input to 702 1 is set to a DC reference source The ROTATION PWM waveform controls the Rotation by varying the duty cycle of the waveform 91 Vertical Key The Vertical Key adjustment can only be performed via the DAS Soft ware The DSP 1002 59 VDF2 outputs the D TILT triangle wave form and is routed to the D Board The D TILT waveform via R736 is applied to the DC reference source which is input to IC702 1 When the Vertical Key adjustment is performed the D TILT triangle waveform varies in shape and as a result the DC reference source is varied by the D TILT waveform The D TILT waveform controls the Vertical Key by varying the shape of the waveform 1001 MICRO PWM4 R1072 P4 4 P6 1 P6 0 6 SCLL SDA IC702 ROTATION LA6500 CN1001 CN801 ROTATION V KEY 92 NC ROTATION INC RUS
46. ng Safety WARNING Before attempting to repair the power supply or any other circuit safety should be considered first Never connect test probes to the primary side circuits unless proper isolation has been provided If isolation for the AC main input is not provided serious harm can result Never as sume you are safe Troubleshooting HINT Visual inspection can play an essential part in any troubleshooting tech nique A Visual inspection of components can lead to the problem area and the repair of the circuit at fault Your eyes may be your best trouble shooting tools to use Overall Block N Board The N Board is mounted to the D Board via connectors CN1001 and CN801 The Microprocessor 1001 EEPROM 1005 and the DSP Digital Signal Processor 1002 are located on the board 1 1001 receives control inputs from the front panel buttons H board and the front and rear video inputs via the A board 1001 responds to the Tim ing and Sync parameters of the video inputs 1001 communicates with 1005 via the bus 1005 contains the operation set up factory preset and user preset data and is utilized by 1001 to control the moni tor circuits and to match the operating parameters to the input signals 1001 also controls 1C 1002 via the bus and provides IC 1002 with the necessary timing and sync parameters 1001 directly controls Input switching Rotation H Cent H Lin Bal Degauss Power Shut
47. nking pulse to the A Board to mute the video CN801 CN1001 12 P3 4 RXCLK 1001 P6 0 SDAI PWM P6 1 NO P4 0 SCLI FLYBACK IC401 e TDAB177 REMOTE ON OFF CC D BOARD 402 401 SUPPLY IC1007 CN801 CN1001 54053 2 SDA SCL V DY T5 FA 3IV SAWN Q us C406 R410 R1061 N IC1002 R1068 R405 E M v w L lt 5 R405 R404 R406 R1052 BOARD VERTICAL RUS9818 1117 4 1 99 88 Vertical Protection Vertical Protection The vertical flyback pulse from IC401 3 through R407 is rectified by D405 and filtered by C409 The DC voltage V FBP is routed to the N Board to Micro 1 1001 42 1001 monitors the DC voltage to confirm that Verti cal Deflection is operating When the DC voltage reaches OV IC1001 7 REMOTE ON OFF goes L 0V to set the power supply in the Active Off mode 89 NOTE LED illuminates Orange 1 5 seconds Off 0 5 seconds 401 TDA8177 CN801 CN1001 R405 R404 D BOARD POWER SUPPLY CN801 CN1001 R406 12 P3 4 RXCLK 1001 P6 0 SDAI PWM P6 1 NO P4 0 SCLI IC1007 1 2 R1053 VERTICAL PROTECTION 90 REMOTE ON OFF D BOARD POWER SUPPLY SDA SCL 1002 DSP RUS9833 1142 4 1 99 Rotation and Vertical Key Circuits Rotation Rotatio
48. oduce 7V DC used for 5 12V Regulator 605 and 6 3V Heater regulator 604 the H used for Horizontal Centering The output at T601 12 through R622 is rectified by D649 to produce the H used for Horizontal Centering The output at T601 11 is used for the H and H floating ground refer ence The H and H voltages in reference to floating ground are 8V NOTE Care should be taken not to short the floating ground to the sec ondary ground SECONDARY VOLTAGES OUTPUT OFF Active OFF Suspend Standby Active 0 145V 145V 183V 80V 0 62V 62V 80V 16V 0 9V 9V 16V 16V 0 12V 12V 16V 12V 0 0 0 12V 8V 0 5 5V 5 5V 7V 5V 0 5V 5V 5V Heaters 0 0 3 2V 6 3V H Centerin 0 5V 5V 8V T601 SRT SWITCHING TRANSFORMER Q602 POWER SW IRF1B44 LCLF65 FW D654 R474 D655 C618 T zi 36 654 0652 big L652 rBeo1 6527 651 0651 C651 5 0650 C650 R622 ea 619 615 604 1650 K H D649 C657 HN R621 C656 L 0648 15548 REMOTE ON OFF BOARD IC1001 7 FB SD OUT GND CFI CCP TR VCC CLH OCP ENABLE IC601 POWER SUPPY CONTROL CONTROL AN8037 IC603 4 SECONDARY VOLTAGES RUS9829 1138 5 24 99 16 Active and Suspend Standby Operation The power supply enters the Active Off and Suspend Standby mode under the
49. om T601 VCC winding If the voltage on this pin exceeds 19 4V DC OVP is activated and the power supply shuts off and can only be restarted by disconnecting and reconnecting the AC line Under voltage lock out UVP occurs when the voltage is less than 9 5V DC Used for the OVP and timer latch functions A capacitor determines the timing for OVP function Feedback terminal 1601 SRT SWITCHING TRANSFORMER OUT GND CFI CCP TR 7 606 IC601 POWER SUPPY CONTROL CONTROL AN8037 vC IC603 4 START UP TROUBLESHOOTING 26 Q605 REMOTE ON OFF N BOARD 1C1001 7 RUS32 1141 4 1 99 Secondary Short Circuit Protection Short Circuit Protection for the secondary low voltage supplies are de tected in different ways 1 The B DET line is used to detect the loss of the 16V DC supply through circuit elements R611 and R612 R611 is connected to the 5V DC from IC605 and R612 is connected to the 16V DC supply from T601 The node voltage between R611 and R612 is monitored by the Micro IC 1001 14 Board If the node voltage exceeds 2V DC 1001 6 goes H 5V turning Q657 ON shunting normal regu lation feedback This causes IC601 to increase the drive output to the point of OVP latch via pin 7 VCC Note LED illuminates Orange 0 5 seconds Off 0 5 seconds 27 2 The 16V 12V and 5V DC secondary voltages are monitored through circuit elements D641 Q640 and
50. ondary ground SECONDARY VOLTAGES OUTPUT 1 Active OFF Suspend Standby Active 145V 145V 183V 80 62 62V 80V 16V 9V 9V 16V 16V 12V 12V 16V 12V 0 0 12V 8V 5 5V 5 5 7V 5V 5V 5V 5V Heaters 0 3 2 6 3 JO O O O O T H Centering 5V 5V 8V 1601 SRT SWITCHING TRANSFORMER OUT GND CFI CCP TR 7 606 IC601 POWER SUPPY CONTROL CONTROL AN8037 vC IC603 4 START UP SECONDARY VOLTAGES 20 Q605 REMOTE ON OFF N BOARD 1C1001 7 RUS9830 1139 4 1 99 Power Supply Protection Circuits OVP Over Voltage Protection During normal Active On operation the output of T601 8 through R623 is rectified by D605 and provides 17V DC through D624 and D657 to 601 7 VCC In the event that the regulation or feedback loops fail the sec ondary output voltages may rise rapidly The output of T601 8 would also rise and is sensed at 601 7 VCC which internally has a threshold of approximately 19V DC Once this threshold is reached 601 6 will latch to eliminate drive to Q602 resulting in power supply shut down Once 601 is latched you must turn the AC power OFF and ON again to restart the power supply UVP Under Voltage Protection The input at 1 601 7 VCC is also used to sense an Under Voltage con
51. outputs correction data via the data bus to the Board for proper Size and Centering calculations This corrects the H Phase H Size and V Size Centering of the video sig nal 003 8 AV 003 7 HFLY R B SCL SDA Bur 78 IN G 62 9 c IN RGB DRIVE OUT 9 SYNC IN QDR 8 OSD XTAL OUT CSDA ee 6 CSCL FROM H_SYNG BOARD CN1003 HRTRC OSD ASC GPE RUS9823 1122 3 15 99 44 Sub Contrast Cutoff control The Sub Contrast levels can only be set by the DAS CATS software for White Balance adjustment When Sub Contrast is adjusted the Micro 1001 Board via the bus instructs 001 to vary the DC level of pin 3 pin 4 G and 5 The DC levels are then input to CUTOFF AMP 1 004 pin 1 B IN pin 3 G IN and pin 4 R IN The output of 4 pin 7 R OUT 10 G OUT and pin 13 B OUT are used to set the DC level of the R G B cathodes respectively The 180 DC with pull up resistors R109 R209 and R309 and 0106 0206 and D306 form the voltage divider network for the R G B cutoffs respec tively 45 Brightness and Contract control The Brightness and Contrast levels can be controlled either by the user or via DAS CATS software When Brightness is adjusted the Micro IC 1001 Board via the bus instructs 001 to vary the DC pedestal level of the RG
52. r and Q507 HLC CTRL Horizontal Lin earity can only be adjusted using the DAS Software The H LIN BAL control is applied to Q507 L502 HLC and the primary of T503 LCT are in parallel The secondary of T503 is controlled by the conduction of Q507 which varies the voltage across the winding This voltage across the secondary winding changes the inductance of the primary winding of T503 Therefore the Horizontal Linearity is controlled by varying the primary inductance of T503 Horizontal Linearity is also maintained through each of the Timing and Sync parameters of the video inputs 69 5 5 0508 0515 IC1001 MICRO ee CN1001 CN801 9505 H DEFLECTION CIRCUIT H LINEARITY 70 RUS9828 1136 4 1 99 71 Impedance Matching CAPS S CAP Tables The Micro 1 1001 Board controls the Impedance Matching S CAPS Micro IC1001 S CAP Switching NoSyncInput DOS Prompt circuit to match the Timing and Sync parameters of the video inputs The Pin 50 5 CAPS are utilized to switch different capacitors into the horizontal 33 Q513 V 12 1 Pin 1 flection yoke thus changing the impedance 1001 pin 46 55 pin 47 50 0512 45V 45V S4 pin 48 S3 pin 49 S2 pin 50 S1 and pin 53 SO control the S CAP Pin S2 H H circuits comprised of circuit elements Q508 Q509 Q510 Q511 Q512 49 0511 5V 5V Q513 and associated components respectively 1001 outputs a H
53. s Color Restoration Circuit Red only The Color Restoration circuit is comprised of the Micro 1001 Board 001 RGB DRIVE IC003 OSD IC004 CUTOFF AMP CRT and the current sensing components Each of the Red Green and Blue cathode beam current sensing circuits are identical and only the Red cathode beam current circuit will be explained As the video image changes the Red cathode beam current also changes This current change flows through R116 R122 and R108 to CUTOFF AMP 1C004 6 R B C F The P P video level is AC coupled by C121 DC clamped by D120 and rectified by D108 This voltage level is input to 003 22 RCI where it is A D converted by 003 49 This digital value of the Red cathode beam current is stored in an indi vidual register During the White Balance adjustment via the DAS CATS software the average DC level is sensed and stored in the registers Color Restoration Function Red only The Color Restoration function is activated via the OSD menu only after an initial warm up period of approximately 30 minutes When the Color Restoration function is activated the Micro 1001 Board via the bus instructs 003 OSD to output an all white pattern to be displayed on the screen 1003 22 RCI samples the Red beam current input and compares this DC level to the level stored in the register If the levels are not the same 003 outputs correction data via the data bus to IC1001
54. teps up the HDF waveform and via R908 and is applied to the Focus voltage at 901 14 FBT 81 IC703 4 H DF 703 6 H DF OUT OUT IN Y IN 1701 722 732 1002 10 BOARD 3 Q 4 R908 B Y B Y X IC703 H DF OUT IN IN OUT X A REMOTE ON OFF H ANODE OF CRT CRT VIA RED FV LEAD TEE 156902 WN WN 192 7 2 R909 56905 711 BLK FV LEAD BOARD DYNAMIC FOCUS 82 IC1001 7 FROM N BOARD 702 712 gt V DF FROM 6 lt 1C1002 58 710 BOARD RUS9817 1116 4 1 99 Vertical DF The Vertical Dynamic Focus circuit is comprised of circuit elements Q706 and 0707 1002 DSP BOARD pin 58 VDF1 outputs the V DF correction waveform and is applied to Q707 buffered and applied to Q706 Q706 inverts and amplifies the V DF waveform and via R909 is applied to the Focus voltage at T901 15 FBT NOTE 703 11 STBY is controlled by the REMOTE ON OFF logic to disable the outputs of IC703 in the Active Off and Standby Suspend modes NOTE T901 FBT has two Focus controls that can be individually ad justed to perform overall Horizontal and Vertical Focus respectively 83 Q707 B V DF Q706 C V DF OUT IN Y IN 1701 722 732 1002 10 BOARD 3 Q 4 R908 B Y B Y
55. to the convergence yoke When the Static Convergence adjust ment is performed IC1002 varies the DC reference level of the XSC sig nal positive or negative The XSC signal is applied to the convergence yoke to shift the R and B beam landing in the vertical direction 1 704 3 XSC The voltage divider network on the N Board comprised of circuit elements R1102 R1103 and R1007 is routed to the D Board to provide 704 pin 4 and pin 6 INB with a DC bias voltage offset DAC REF 7045 OUT OUT OUT A A INA INA VEE INB B OUT VCC IC1001 MICRO P6 0 SDA1 6 1 CN1001 IC 1002 DSP 0 YOKE N BOARD STATIC CONVERGENCE 94 Dynamic Convergence 1 701 The DSP 1C1002 8 YDC outputs the complex convergence waveform and is routed to the D Board The signal is input to 1 701 2 IN B 1C701 current amplifies the signal and the output at pin 1 OUT B is applied to the convergence yoke When the Dynamic Convergence ad justment is performed 1002 varies the DC reference level shape and size of the YDC signal The YSC signal is applied to the convergence yoke to shift the R and B beam landing in the horizontal direction in the outer areas of the CRT 701 2 YDC The DSP 1C1002 6 outputs the complex convergence waveform and is routed to the D Board The XDC signal is input to 701 5
56. versely proportional to the B 601 6 PWM 13 652 3 is applied to 603 2 to control the feedback output of IC603 4 while maintaining electrical isolation between chassis ground and AC in put ground The signal at IC603 4 is applied to 601 9 FB As a result 601 6 responds accordingly to adjust the duty cycle and frequency out put applied to Q602 by regulating the secondary B 180V DC voltage Q602 Drain T601 TO Res9 16 180V 7 3 gt 16V 16V 2 R631 D632 R631 IC603 IC601 OUT FEED BACK SWITCHING Q657 CCP FB 9 Q657 2 PROTECTION D631 ACTIVE OFF On am REMOTE ON OFF y N BOARD IC1001 7 IC606 OCP ENABLE Q605 CONTROL REGULATION RUS98 7 1065 5 24 99 14 Secondary Voltages 15 The following voltages are produced by T601 SRT 5 The output at T601 18 is rectified by D653 and D656 to produce 16V DC and 16V 2 DC used for the deflection circuits 1 The output at T601 13 is rectified by D650 to produce 183V DC used for deflection and video circuits 6 The output at T601 10 through R621 is rectified by D648 to produce The output at T601 14 is rectified by D651 to produce 80V DC used for video circuits The output at T601 16 is rectified by D652 and D655 to produce 16V DC and 16V 2 DC used for deflection 5 12V Regulator 605 The output at T601 17 is rectified by D654 to pr
57. y OSD ASC Auto Size and Center Sub Contrast Cutoff control Brightness and Contract control G2 control and Spot Killer Color Restoration Color Restoration Circuit Red only Color Restoration Function Red only GPE Graphic Picture Enhancement Standard Mode Presentation Mode Graphic Video Mode Plug and Play VGA What is Plug and Play Display Data Channel Circuit DDC1 DDC2B and DDC2AB DDC Data Format EDID Horizontal Deflection Horizontal Drive 39 39 41 43 43 45 45 47 49 49 49 51 51 51 51 53 53 54 55 55 55 57 59 59 Horizontal AFC Horizontal Size Control Pin Keystone Bow and Geometric Corrections Horizontal Centering Raster only Horizontal Linearity Impedance Matching S CAPS Horizontal Deflection Shutdown Protection High Voltage Circuit High Voltage High Voltage Regulation G2 Screen Voltage ABL Auto Brightness Limiting HV Protection HV Shutdown ABL Shutdown Dynamic Focus DF Circuit Horizontal DF Vertical DF Vertical Deflection Vertical Drive Vertical Geometric Corrections Vertical Centering Vertical Feedback Pulse 61 63 65 67 69 71 73 73 75 75 75 75 77 79 79 79 81 81 83 85 85 85 87 87 Vertical Protection Rotation and Vertical Key Circuits Rotation Vertical Key Convergence Circuits Static Convergence IC704 Dynamic Convergence IC 701 89 91 91 91 93 93 95 098 Chassis Specifications Picture tube
58. y cir ures of rectifier diodes fusible resistors 502 and related components cuit Measure the voltages in reference to the horizontal centering ground HN Typically the voltages are 8V DC However the adjustment set Rectifier Section Troubleshooting ting can reduce the voltages by approximately 1V If there are no prob lems found at the Horizontal Centering supply troubleshoot the Horizon Rectifier diode failures are not common but do occur Deflection D tal Centering circuitry Board Video A Board and N Board failures contribute to diode dam In the event a voltage is not present check for shorts to ground or open or shorted diodes Also check for any open fusible resistor and shorted zener diodes found on the supply lines 1601 SRT SWITCHING TRANSFORMER OUT GND CFI CCP TR 7 606 IC601 POWER SUPPY CONTROL CONTROL AN8037 vC IC603 4 START UP TROUBLESHOOTING 30 Q605 REMOTE ON OFF N BOARD 1C1001 7 RUS32 1141 4 1 99 5V Standby Circuit During Active Off and Suspend Standby modes the 8V DC secondary supply applied to 605 1 INPUT1 and Q601 C is reduced to 5 5V DC In order to prevent loss of the 5V DC Standby it is necessary to supply a back up voltage During Active Off mode the 16V DC secondary supply source is re duced to 9V DC and is applied Q601 E Q607 is OFF which turns Q606 and 0601 ON 06
59. ying the am plitude The V SAWN waveform controls the Vertical Linearity by varying the shape CN801 CN1001 12 P3 4 RXCLK 1001 P6 0 SDAI PWM P6 1 NO P4 0 SCLI FLYBACK IC401 e TDAB177 REMOTE ON OFF CC D BOARD 402 401 SUPPLY IC1007 CN801 CN1001 54053 2 SDA SCL V DY T5 FA 3IV SAWN Q us C406 R410 R1061 N IC1002 R1068 R405 E M v w L lt 5 R405 R404 R406 R1052 BOARD VERTICAL RUS9818 1117 4 1 99 86 Vertical Centering Vertical Centering is performed by varying the DC offset of the V SAWN waveform in respects to the DCC2 reference voltage The DC shift is proportional to the direction of the raster As the DC shift is more positive the raster is moved upwards and as the DC shift is made less positive the raster is moved downwards CN801 13 VSAWN Remember the V SAWN waveform controls the Vertical Centering by varying the DC Offset with respects to the DCC2 reference voltage 87 Vertical Feedback Pulse The vertical flyback pulse from IC401 3 through R407 is rectified by D405 and filtered by C409 The DC voltage V FBP is routed to the N Board to IC 1002 39 V FBK 1002 monitors the DC voltage to confirm that Ver tical Deflection is operating When the DC voltage is OV 1C 1002 40 disables the bla
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