Planar LC1200R - Manual (Page 15)

LC1200R User’s Guide 021-0183-00 Rev A 15 of 29
4.4 Timing and Frequency
4.4.1 Video, Horizontal and Vertical Sync
Figure 6 illustrate video timing relationships the LC1200R operates within when the specified
video mode (Table 5 Video Mode Definitions) is applied.
Front Porch defines the time from end of active video data to the start of Horiz/Vert Sync
Pulse.
Back Porch defines the time from end of Horiz/Vert Sync Pulse to the start of active video
data.
Blanking is the total time comprising Front Porch, Back Porch and Sync Pulse time(s).
The horizontal sync circuitry synchronizes to horizontal frequencies of 31.468 KHz ±0.5 KHz,
48.077KHz ±0.5KHz, and 56.476KHz ±0.5KHz. Horizontal sync pulse width variation is 1.813-
µsec to 3.813-µsec. The LC1200R will "sync" to the specified format vertical frequencies
between 60Hz and 72Hz without adjustment.
Absence of Horizontal and/or Vertical Sync will not damage the LC1200R.
4.5 Video Signal On-Off Sequences
The sequence for bringing up and removal of each video input signal can be in any sequence or
combination of input signals.
Table Table Table Table 6 6 6 6.... Video Mode Timing Data Video Mode Timing Data Video Mode Timing Data Video Mode Timing Data
Video Modes
IBM VGA VESA
Resolution 640x400 640x480 800x600 1024x768
Video Clock 25.175 MHz 25.175 MHz 50.000 MHz 75.000 MHz
Horizontal Scan
Freq.
31.468 KHz 31.468 KHz 48.077 KHz 56.476 KHz
Horizontal Line
Period 31.778 us 800
pixels 31.778 us 800
pixels 20.800 us 1040
pixels 17.707 us 1328
pixels
Horizontal
Blanking 6.356 us 160
pixels 6.356 us 160
pixels 4.800 us 240
pixels 4.053 um 304
pixels
Horizontal Sync
Pulse
3.813 us 96 pixels 3.813 us 96 pixels
2.400 us 120
pixels 1.813 us 136
pixels
Horizontal Front
Porch
0.636 us 16 pixels 0.636 us 16 pixels 1.120 us 56 pixels 0.320 us 24 pixels
Horizontal Back
Porch
1.907 us 48 pixels 1.907 us 48 pixels 1.280 us 64 pixels
1.920 us 144
pixels
Horizontal Active
Display 25.422 us 640
pixels 25.422 us 640
pixels 16.000 us 800
pixels 13.653 us 1024
pixels
Horizontal Sync
Polarity
- - - -
Vertical Scan Freq. 70.087 Hz 59.94 Hz 72.184 Hz 70.069
Vertical Frame
Period 14.268 ms 449
lines 16.683ms 525
lines 13.853 ms 666
lines 14.272 ms 806
lines
Vertical Blanking 1.557 ms 49 line 1.430 ms 45 line 1.373 ms 66 lines 0.673 ms 38 lines
Vertical Sync 0.064 ms 2 lines 0.064 ms 2 lines 0.125 ms 6 lines 0.106 ms 6 lines