CHRONTEL
Modes of Operation
CH7009A
6
201-0000-035 Rev 1.1, 5/8/2000
The CH7009 is capable of being operated as a single DVI output link, or as a VGA to TV encoder. The two
modes of operation cannot be used simultaneously. Descriptions of each of the operating modes, with a block
diagram of the data flow within the device is shown below.
DVI Output
In DVI Output mode, multiplexed input data, sync and clock signals are input to the CH7009 from the graphics
controllers digital output port. Data will be 2X multiplexed, and the clock inputs can be 1X or 2X times the
pixel rate. Some examples of modes supported are shown in the table below, and a block diagram of the
CH7009 is shown on the following page. For the table below, clock frequencies for given modes were taken
from VESA DISPLAY MONITOR TIMING SPECIFICATIONS if they were detailed there, not VESA
TIMING DEFINITION FOR FLAT PANEL MONITORS. The device is not dependent upon this set of timing
specifications. Any values of pixels/line, lines/frame and clock rate are acceptable, as long as the pixel rate
remains below 165MHz. In the block diagram, all blocks are shown. Those blocks which are non-active are
shown as shaded. The clock and data paths which are in use are highlighted. Although the block diagram does
not show this path as being active, the data input can be selected to be output by the DACs as a VGA type
output. For correct DVI operation, the input data format must be selected to be one of the RGB input formats.
1
These DVD compatible modes are input in a non-interlaced RGB data format
2
30Hz in progressive scan modes, 60Hz in interlaced modes
Table 2: DVI Output
Graphics
Resolution
Active
Aspect Ratio
Pixel Aspect
Ratio
Refresh Rate
(Hz)
XCLK
Frequency
(MHz)
<35.5
<31.5
<36
27
27
<57
<95
<67
<158
<165
<140
DVI
Frequency
(MHz)
<355
<315
<360
270
270
<570
<950
<670
<1580
<1650
<1400
720x400
640x400
640x480
720x480
1
720x576
1
800x600
1024x768
1280x720
1280x1024
1600x1200
1920x1080
4:3
8:5
4:3
4:3
4:3
4:3
4:3
16:9
4:3
4:3
16:9
1.35:1.00
1:1
1:1
9:8
15:12
1:1
1:1
1:1
1:1
1:1
1:1
<85
<85
<85
59.94
50
<85
<85
<60
<85
<60
<30
2