GS4911B Datasheet, PDF (41/113 Pages) Gennum Corporation – HD/SD/Graphics Clock and Timing Generator with GENLOCK

GS4911B/GS4910B Data Sheet
Figure 3-2 summarizes the differences in output accuracy in each mode of
operation. Assuming a crystal reference of +/-100ppm, in Free Run mode the
frequency of the output clock and timing signals will be as accurate as the crystal.
In Genlock mode the frequency will be as accurate as the input reference
regardless of the crystal accuracy. In Freeze mode, the frequency of the output
clock and timing signals will be maintained to within +/- 2ppm.
Assumption: Reference
XTAL is 27MHz+/-100ppm
+t
t
+100ppm
74.25 MHz
-100ppm
-t
+t
+2ppm
-2ppm
-t
Free Run _{Genlock Freeze}
No Input
Reference
Reference
Applied
Reference
Lost
Time
NOTES:
1. t represents the temperature variability of the crystal
2. Diagram not to scale.
Figure 3-2: Output Accuracy and Modes of Operation
36655 - 2 April 2006
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