ViewSonic VX800-3, Service Manual

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Digital Timing Mode Table
1 2 3 4 5 6 7
Signal name symbol TEXT
mode
TEXT
mode
VGA VGA VESA-VG
A
VESA-VG
A
VESA-VG
A
H-frequency (kHz) 31.468 31.469 31.468 31.468 37.5 37.862 43.269
V-frequency (Hz) 70.087 70.087 60.000 59.941 75 72.807 85.005
Pixel rate (MHz) 25.175 28.322 25.175 25.175 31.5 31.501 36.000
H-sync Ths 96 108
96
96 64 40 56
H-back porch Thb 48 54
48
48 120 128 80
Count num
(H-total)
Thd 800 900
800
800 840 832 832
H- front porch Thf 16 18
16
16 16 24 56
V-sync Tvs 2 2
2
2 3 3 3
V-back porch Tvb 60 35
35
33 16 28 25
Count num
(V-total)
Tvd 449 449
449
525 500 520 509
V-front porch Tvf 37 12
10
6 1 9 1
H-sync. Polarity Positive Negative Negative Negative Negative Negative Negative
V-sync Polarity Negative Positive Negative Negative Negative Negative Negative
H-resolution (dots) 640 720 640 640 640 640 640
V-resolution (lines) 350 400 400 480 480 480 480
8 9 10 11 12 13 14
Signal name Symbo
l
IBM-8514A SVGA SVGA SVGA SVGA XGA XGA
H-frequency (kHz) 35.156 37.879 48.077 46.875 53.674 48.363 56.476
V-frequency (Hz) 56.250 60.317 72.188 75.000 85.061 60.004 70.069
Pixel rate (MHz) 36.000 40.000 50.000 49.500 56.250 65.000 75.000
H-sync Ths 72 128 120 80 64 136 136
H-back porch Thb 128 88 64 160 152 160 144
Count num
(H-total)
Thd 1024 1056 1040 1056 1048 1344 1328
H- front porch Thf 24 40 56 16 32 24 24
28
ViewSonic Corporation
Confidential – Do Not Copy
VX 8 00-3