ch7301c Chrontel, ch7301c Datasheet - Page 6

• Manufacturer Part Number: ch7301c
• Description: Ch7301 Dvi Transmitter
• Manufacturer: Chrontel

CHRONTEL
2. M
The CH7301C is capable of being operated as a single DVI output link. Descriptions of the single DVI output link
operating mode, with a block diagram of the data flow within the device is shown on Figure 1.
2.1 RGB Bypass
In RGB Bypass mode, data, sync and clock signals are input to the CH7301C from a graphics device, and bypassed
directly to the D/A converters to implment a second CRT DAC function. External sync signals must be supplied from the
graphics device. These sync signals are buffered internally, and can be output to drive the CRT. The input data format can
be either YCrCb or RGB in this operating mode (See description for register 56h, bit[0). Input data is 2X multiplexed,
and the XCLK clock signal can be 1X or 2X times the pixel rate. The CH7301C can support a pixel rate of 165MHz.
This operating mode uses all 10 bits of the DAC’s 10-bit range, and provides a nominal signal swing of 0.661V (or 0.7V
depending on DAC Gain setting in control registers) when driving a 75
conversion or flicker filtering is applied in RGB bypass.
2.2 DVI Output
In DVI Output mode, multiplexed input data, sync and clock signals are input to the CH7301C from the graphics
controller’s 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 CH7301C 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. For correct DVI operation, the input data
format must be selected to be one of the RGB input formats.
6
Table 2. DVI Outputs
1920x1080
1280x1024
1360x1024
1400x1050
1600x1200
Resolution
1024x768
1280x720
1280x768
1366x768
Graphics
720x400
640x400
640x480
720x480
720x576
800x600
1
ODES OF
This mode is implemented with reduced blanking.
1
Aspect
Active
Ratio
16:9
15:9
16:9
16:9
4:3
8:5
4:3
4:3
4:3
4:3
4:3
4:3
4:3
4:3
4:3
O
PERATION
1.35:1.00
Aspect
15:12
Ratio
Pixel
1:1
1:1
9:8
1:1
1:1
1:1
1:1
1:1
1:1
1:1
1:1
1:1
1:1
Rate (Hz)
Refresh
59.94
<85
<85
<85
<85
<85
<85
<85
<85
<85
<75
<75
<60
<60
50
Frequency
XCLK
(MHz)
<35.5
<31.5
<110
<119
<158
<140
<145
<156
<165
<165
<36
<57
<95
27
27
Frequency
Ω
(Mbits)
<1100
<1190
<1580
<1400
<1450
<1560
<1650
<1650
<355
<315
<360
<570
<950
DVI
270
270
doubly terminated load. No scaling, scan
201-0000-056
Rev. 1.32,
CH7301C
5/24/2005