SAA6752HS/V103 PHILIPS [NXP Semiconductors], SAA6752HS/V103 Datasheet - Page 34

• Manufacturer Part Number: SAA6752HS/V103
• Description: MPEG-2 video and MPEG-audio/AC-3 audio encoder with multiplexer
• Manufacturer: PHILIPS [NXP Semiconductors]

Philips Semiconductors
7.9
7.9.1
The SAA6752HS is designed to operate with a single
fundamental 27 MHz crystal or an external 27 MHz clock.
From these clock sources an internal PLL produces the
27 MHz, 54 MHz and 108 MHz frequencies needed for
operation.
It is possible to use a third overtone crystal in combination
with a 9 MHz external trap. In this event Clock mode 2 and
tuning by the I
7.9.2
The following configuration options can be selected from
the host:
Table 9 Clock modes
Note
1. The stream contents are MPEG-compliant but the time stamps are not synchronized with real time (i.e. dependent
Table 10 Clock modes requirements
Note
1. The nominal video frame frequency is dependent on the video mode set: 525 or 625 lines.
2004 Jan 26
CLOCK
CLOCK
MODE
MODE
CLOCK MODE. Dependent on the type of application
(i.e. video frame locked, reference clock locked etc.),
three different clock modes are available
CLOCK SOURCE. The clock can be generated from an
internal crystal controlled clock or an external source.
If from a crystal then a fine tune adjustment is available
MPEG-2 video and MPEG-audio/AC-3
audio encoder with multiplexer
on the accuracy of the video input frame frequency). Playback of such a stream is MPEG-compliant due to the
re-generation of time synchronization.
1
2
3
1
2
3
Clock generation
G
C
LOCK CONFIGURATION OPTIONS
ENERAL
DVD-compliant
DVD and MPEG-compliant
MPEG-compliant
27 MHz 0.1%
27
(to allow fine tuning via PLL)
27
TIME-STAMP COMPLIANCE
CRYSTAL FREQUENCY
2
C-bus commands are not usable.
(1 200
(1 30
OUTPUT STREAM
10
(1)
10
6
) MHz
6
) MHz
crystal frequency
27 MHz
frequency accuracy
crystal frequency
27 MHz 0.1%
not applicable
27
SYSTEM FREQUENCY
CLOCK FREQUENCY
(1 30
EXTERNAL
video frame
10
34
6
7.9.3
The SAA6752HS internal PLL can be configured in three
different clock modes: Clock modes 1, 2 and 3. A definition
of the clock modes is shown in Table 9. The clock modes
are intended for different applications:
To meet the requirements for each clock mode the
conditions specified in Table 10 must be met.
) MHz
CLOCK OUTPUT. It is possible to enable a system clock
output so that the 27 MHz clock can be used elsewhere
by the user.
Clock mode 1. System clock reference locked to input
video frame frequency. Intended for applications where
the output stream is recorded directly onto a medium
(i.e. DVD video recorder).
Clock mode 2. Crystal locked to input video frame
frequency. Intended for applications that require both
recording and direct playback. However it is limited by
the required accuracy of the input video frame frequency
Clock mode 3. Crystal free-running. Intended for
applications where the output stream is played real time
directly by a decoder.
C
SYSTEM CLOCK REFERENCE FREQUENCY
27 MHz
27 MHz
crystal frequency
nominal
nominal
not applicable
LOCK
INPUT VIDEO FRAME FREQUENCY
M
ODES
video frame frequency accuracy
video frame frequency accuracy
8% to nominal + 2%
(1 200
10
6
)
SAA6752HS
Product specification
(1)