ch7011a Chrontel, ch7011a Datasheet - Page 6

• Manufacturer Part Number: ch7011a
• Description: Ch7011 Tv Output Device
• Manufacturer: Chrontel

CHRONTEL
4. M
The CH7011 is capable of being operated as a VGA to TV encoder. Descriptions of the encoder operating
modes, with a block diagram of the data flow within the device is shown below.
4.1 TV Output
In TV Output mode, multiplexed input data, sync and clock signals are input to the CH7011 from the graphics
controller’s digital output port. A P-OUT clock can be output as a frequency reference to the graphics
controller, which is recommended to ensure accurate frequency generation. Horizontal and vertical sync
signals are normally sent to the CH7011 from the graphics controller, but can be output to the graphics
controller as an option. Data will be 2X multiplexed, and the XCLK clock signal can be 1X or 2X times the
pixel rate. The input data will be encoded into the selected video standard, and output from the video DAC’s.
The modes supported for TV output are shown in the table below, and a block diagram of the CH7011 is shown
on the following page.
1
2
6
Graphics
Resolution
512x384
512x384
720x400
720x400
640x400
640x400
640x480
640x480
720x480
720x480
720x576
720x576
800x600
800x600
1024x768
1024x768
Table 2. TV Output Modes
These DVD modes operate with interlaced input, scan conversion and flicker filter are bypassed.
These DVD modes operate with non-interlaced input, scan conversion is not bypassed.
MUST BE used for each DAC connecting to TV (Refer to AN-38 for details).
In order to minimize the hazard of ESD, a set of protection diodes
ODES OF
1
2
1
2
Active Aspect
O
Ratio
4:3
4:3
4:3
4:3
8:5
8:5
4:3
4:3
4:3
4:3
4:3
4:3
4:3
4:3
4:3
4:3
PERATION
Pixel Aspect
1.35:1.00
1.35:1.00
15:12
15:12
Ratio
1:1
1:1
1:1
1:1
1:1
1:1
9:8
9:8
1:1
1:1
1:1
1:1
TV Output Stan-
NTSC
NTSC
NTSC
NTSC
NTSC
NTSC
NTSC
NTSC
PAL
PAL
PAL
PAL
PAL
PAL
PAL
PAL
dard
Scaling Ratios
3/4, 7/10, 5/8
5/4, 1/1, 7/8
5/4, 1/1, 5/6
1/1, 7/8, 5/6
1/1, 7/8, 5/6
1/1, 5/6, 5/7
1/1, 5/6, 5/7
5/7, 5/8, 5/9
5/8, 5/9, 1/2
5/4, 1/1
5/4, 1/1
5/4, 1/1
5/4, 1/1
5/4, 1/1
1/1
1/1
201-0000-037 Rev 2.1, 10/20/2004
CH7011A