saa7120 NXP Semiconductors, saa7120 Datasheet - Page 6

• Manufacturer Part Number: saa7120
• Description: Digital Video Encoder Condenc
• Manufacturer: NXP Semiconductors

Philips Semiconductors
FUNCTIONAL DESCRIPTION
The digital video encoder (ConDENC) encodes digital
luminance and colour difference signals simultaneously
into analog CVBS and S-Video signals. NTSC-M,
PAL B/G, and sub-standards are supported.
Both interlaced and non-interlaced operation is possible
for all standards.
The basic encoder function consists of subcarrier
generation, colour modulation and the insertion of
synchronization signals. Luminance and chrominance
signals are filtered in accordance with the standard
requirements of “RS-170-A” and “CCIR 624” .
For ease of analog post-filtering the signals are
oversampled twice with respect to the pixel clock prior to
digital-to-analog conversion.
The filter characteristics are shown in Figs 3 and 4.
The DACs for Y, C, and CVBS have 10-bit resolution.
The 8-bit multiplexed Cb-Y-Cr formats are “CCIR 656”
(D1 format) compatible, but the SAV and EAV codes can
1997 Jan 06
handbook, full pagewidth
Digital Video Encoder (ConDENC)
(1) CCRS1 = 0; CCRS0 = 1.
(2) CCRS1 = 1; CCRS0 = 0.
(dB)
G v
12
18
24
30
36
42
48
54
6
0
6
0
2
(3) CCRS1 = 0; CCRS0 = 0.
(4) CCRS1 = 1; CCRS0 = 1.
(4)
Fig.3 Luminance transfer characteristic 1.
4
(3)
(1)
6
(2)
6
be decoded optionally when the device is to operate in
slave mode.
It is also possible to connect a Philips Digital Video
Decoder (SAA7111 or SAA7151B) to the ConDENC.
Via pin RTCI, connected to RTCO of a decoder,
information concerning the actual subcarrier, PAL-ID and
(if used in conjunction with the SAA7111) the subcarrier
phase can be inserted.
The ConDENC synthesizes all necessary internal signals,
colour subcarrier frequency and synchronization signals.
Wide screen signalling data can be loaded via the I
It is inserted into line 23 for 50 Hz field rate standards.
The IC contains closed caption and extended data
services encoding (line 21), and supports anti-taping
signal generation in accordance with Macrovision.
Possibilities are provided for setting video parameters:
Black and blanking level control
Colour subcarrier frequency
Variable burst amplitude.
8
10
SAA7120; SAA7121
Preliminary specification
12
f (MHz)
MGD672
14
2
C-bus.