Service manual

ELECTRICAL REQUIREMENT
Horizontal / Vertical Frequency
Horizontal Frequency 30 – 82 KHZ
Vertical Refresh Rate 56– 76 HZ.
Maximum Pixel Clock 156 MHz
Sync Polarity Independent of sync polarity.
Timing Table
Item Timing Analog Digital
1. 640 x 400 @ 70Hz, 31.5kHz Yes Yes
2. 640 x 480 @ 60Hz, 31.5kHz Yes Yes
3. 640 x 480 @ 67Hz, 35.0kHz Yes Yes
4. 640 x 480 @ 72Hz, 37.9kHz Yes Yes
5. 640 x 480 @ 75Hz, 37.5kHz Yes Yes
6. 720 x 400 @ 70Hz, 31.5kHz Yes Yes
7. 800 x 600 @ 56Hz, 35.1kHz Yes Yes
8. 800 x 600 @ 60Hz, 37.9kHz Yes Yes
9. 800 x 600 @ 75Hz, 46.9kHz Yes Yes
10. 800 x 600 @ 72Hz, 48.1kHz Yes Yes
11. 832 x 624 @ 75Hz, 49.7kHz Yes Yes
12. 1024 x 768 @ 60Hz, 48.4kHz Yes Yes
13. 1024 x 768 @ 70Hz, 56.5kHz Yes Yes
14. 1152X 864 @75Hz, 67.5kHz Yes Yes
15. 1152X 870 @75Hz, 70.8kHz Yes Yes
16. 1024 x 768 @ 75Hz, 60.0kHz Yes Yes
17. 1280 x 1024 @ 60Hz, 63.4kHz Yes Yes
18. 1280 x 1024 @ 75Hz, 79.97kHz Yes Yes
19. 1400x 1050 @ 60Hz, 65.3kHz Yes Yes
Primary Presets
“1400 x 1050” @ 60Hz
User Presets
Number of User Presets (recognized timings) Available: 10 presets total in FIFO configuration
Changing Modes
l Maximum Mode Change Blank Time for image stability : 3 seconds (Max), excluding
“Auto Adjust” time
l Under DOS mode (640 x 350, 720 x 400 & 640 x 400), it should recall factory setting
when execute “Auto Adjust”
l The monitor needs to do “Auto Adjust” the first time a new mode is detected
l (see section “0-Touch™ Function Actions”)
l While running Change Mode, Auto Adjust or Memory Recall, the image shall blank
ViewSonic Corporation
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VG2021m-1 Confidential - Do Not Copy