GS4911B/GS4910B HD/SD/Graphics Clock and Timing Generator with GENLOCK
Key Features
Description
Video Clock Synthesis
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Generates any video or graphics clock up to 165MHz
Pre-programmed for 8 video and 13 graphics clocks
Accuracy of free-running clock frequency limited only by
crystal reference
One differential and two single-ended video/graphics clock
outputs
Each clock may be individually delayed for skew control
Video output clock may be directly connected to Gennum’s
serializers for a SMPTE-compliant HD-SDI output
Audio Clock Synthesis (GS4911B only)
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Three audio clock outputs
Generates any audio clock up to 512*96kHz
Pre-programmed for 7 audio clocks
Timing Generation
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Generates up to 8 timing signals at a time
Choose from 9 pre-programmed timing signals: H and V sync
and blanking, F Sync, F Digital, AFS (GS4911B only), Display
Enable, 10FID, and up to 4 user-defined timing signals
Pre-programmed to generate timing for 35 different video
formats and 13 different graphic display formats
Genlock Capability
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Clocks may be free-running or genlocked to an input
reference with a variable offset step size of 100-200ps
(depending on exact clock frequency)
Variable timing offset step size of 100-200ps up to one frame
Output may be cross-locked to a different input reference
Freeze operation on loss of reference
Optional crash or drift lock on application of reference
Automatic input format detection
General Features
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Reduces design complexity and saves board space - 9mm x
9mm package plus crystal reference replaces multiple
VCXOs, PLLs and timing generators
Pb-free and RoHS Compliant
Low power operation typically 300mW
1.8V core and 1.8V or 3.3V I/O power supplies
64-PIN QFN package
The GS4911B is a highly flexible, digitally controlled clock
synthesis circuit and timing generator with genlock capability. It
can be used to generate video and audio clocks and timing signals,
and allows multiple devices to be genlocked to an input reference.
The GS4910B includes all the features of the GS4911B, but does
not offer audio clocks or AFS pulse generation.
The GS4911B/GS4910B will recognize input reference signals
conforming to 36 different video standards and 16 different
graphic formats, and will genlock the output timing information to
the incoming reference. The GS4911B/GS4910B supports
cross-locking, allowing the output to be genlocked to an incoming
reference that is different from the output video standard
selected.
The user may select to output one of 8 different video sample
clock rates or 13 different graphic display clock rates, or may
program any clock frequency between 13.5MHz and 165MHz.
The chosen clock frequency can be further divided using internal
dividers, and is available on two video clock outputs and one
LVDS video clock output pair. The video clocks are frequency and
phased-locked to the horizontal timing reference, and can be
individually delayed with respect to the timing outputs for clock
skew control.
Eight user-selectable timing outputs are provided that can
automatically produce the following timing signals for 35
different video formats and 13 different graphics formats: HSync,
Hblanking, VSync, Vblanking, F sync, F digital, AFS (GS4911B
only), DE, and 10FID. These timing outputs may be locked to the
input reference signal for genlock timing and may be phase
adjusted via internal registers.
In addition, the GS4911B provides three audio sample clock
outputs that can produce audio clocks up to 512fs with fs ranging
from 9.7kHz to 96kHz. Audio to video phasing is accomplished by
an external 10FID input reference, a 10FID signal specified via
internal registers, or a user-programmed audio frame sequence.
The GS4911B/GS4910B is Pb-free, and the encapsulation
compound does not contain halogenated flame retardant (RoHS
Compliant).
Applications
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Video cameras; Digital audio and/or video recording/play
back devices; Digital audio and/or video processing devices;
Computer/video displays; DVD/MPEG devices; Digital Set
top boxes; Video projectors; High definition video systems;
Multi-media PC applications
GS4911B/GS4910B HD/SD/Graphics Clock and Timing
Generator with GENLOCK
Data Sheet
36655 - 5
June 2009
www.gennum.com
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