GS4911B_09 Datasheet, PDF (12/119 Pages) Gennum Corporation – HD/SD/Graphics Clock and Timing Generator with GENLOCK

Table 1-1: Pin Descriptions (Continued)
Pin
Number
17
Name
VSYNC
18, 31, 38, IO_VDD
50, 62
19
FSYNC
Timing
Type Description
Non
Input
Synchronous
–
Power
Supply
Non
Input
Synchronous
REFERENCE SIGNAL INPUT
Signal levels are LVCMOS/LVTTL compatible.
The VSYNC external reference signal is applied to this pin by the
application layer. When the GS4911B/GS4910B is operating in
Genlock mode, the device senses the polarity of the VSYNC input
automatically, and references to the leading edge.
If the user wishes to select one of the pre-programmed video and/or
timing output signals provided by the device, then this signal must
adhere to one of the 36 defined video or 16 different graphics
display standards supported by the device. In this mode of
operation, the VSYNC input provides a vertical scanning reference
signal.
The VSYNC signal may have analog timing, such as from a sync
separator, or may be digital such as from an SDI deserializer.
Section 1.4 on page 20 describes the 36 video formats and 16
graphic formats recognized by the GS4911B/GS4910B.
Most positive power supply connection for the digital I/O signals.
Connect to either +1.8V DC or +3.3V DC.
NOTE: All five IO_VDD pins must be powered by the same voltage.
REFERENCE SIGNAL INPUT
Signal levels are LVCMOS/LVTTL compatible.
The FSYNC external reference signal is applied to this pin by the
application layer.
The first field is defined as the field in which the first broad pulse
(also known as serration) is in the first half of a line. The FSYNC
signal should be set HIGH during the first field for sync-based
references.
If the user wishes to select one of the pre-programmed video and/or
timing output signals provided by the device, then this signal must
adhere to one of the 36 defined video or 16 different graphics
display standards supported by the device. In this mode of
operation, the FSYNC input provides an odd/even field input
reference.
The FSYNC signal may have analog timing, such as from a sync
separator, or may be digital such as from an SDI deserializer.
Section 1.4 on page 20 describes the 36 video formats and 16
graphic formats recognized by the GS4911B/GS4910B.
For blanking-based references, the FSYNC signal should be set HIGH
during the second field.
NOTE: If the input reference format does not include an F sync
signal, this pin should be held LOW.
GS4911B/GS4910B HD/SD/Graphics Clock and Timing
Generator with GENLOCK
Data Sheet
36655 - 5
June 2009
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