GV7704 Datasheet, PDF (23/52 Pages) Semtech Corporation – Quad HD-VLC Receiver

Table 4-5: 1080-line Progressive Horizontal Timing
Progressive
H1
H2
30 or 30/1.001 Hz
560
4400
25Hz
1440
5280
24 or 24/1.001 Hz
1660
5500
4.4.3.2 High Definition 720p Output Formats
The Society of Motion Picture and Television Engineers (SMPTE) defines the standard for
progressive scan 720-line HD image formats. SMPTE ST 296-2001 specifies the
representation for 720p digital Y'C'_BC'_R 4:2:2 signals at pixel rates of 74.25MHz or
74.25/1.001 MHz. The GV7704 provides a 10-bit multiplexed output interface, doubling
the pixel clock output rate to 148.5MHz or 148.5/1.001 MHz.
V=1
LINE
1
BLANKING
25
V=0
26
(F=0)
ACTIVE VIDEO
745
V=1
746
BLANKING
750
H=1 H=0
EAV SAV
Figure 4-6: 720p Digital Vertical Timing
The frame rate determines the horizontal timing, which is shown in Table 4-6.
Table 4-6: 720p Horizontal Timing
Frame Rate
25
30 or 30/1.001
50
60 or 60/1.001
H = 1 Sample Number
2560
2560
2560
2560
H = 0 Sample Number
0
0
0
0
Total Samples Per Line
7920
6600
3960
3300
4.4.3.3 BT.656 Video Output Timing Mode
By default, the 10-bit parallel video output will contain two embedded TRS words, as
defined in ITU-R BT.1120. Some commercially available CODEC devices cannot detect
the presence of the double TRS in the HD video stream, and require that the 8/10-bit HD
video contain only one TRS word, as per the ITU-R BT.656 Standard Definition format.
When the BT656_ENABLE bit is HIGH, the GV7704 will re-format the parallel video
output to conform with BT.656 embedded TRS. The device will replace all data words
GV7704
Preliminary Data Sheet Rev.3
PDS-060376
September 2015
www.semtech.com
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Semtech