GS4915 Datasheet, PDF (19/27 Pages) Gennum Corporation – ClockCleaner™

Table 3-4: Output Behaviour in Autobypass Mode
FCTRL[1:0]
Fixed –
74.25MHz [10]
Fixed –
148.5MHz [11]
Input
27MHz
74.25MHz
148.5MHz
Other
27MHz
74.25MHz
148.5MHz
Other
DOUBLE
X
0
1
X
X
X
X
X
X
LOCK
LOW
HIGH
HIGH
LOW
LOW
LOW
LOW
HIGH
LOW
Output
27MHz
74.25MHz
148.5MHz
148.5MHz
Input
27MHz
74.25MHz
148.5MHz
Input
Table 3-5: Output Behaviour in Manual Bypass Mode
FCTRL[1:0]
Input
DOUBLE
LOCK
Output
Auto [00]
27MHz
X
HIGH*
27MHz
74.25MHz
X
HIGH*
74.25MHz
148.5MHz
X
HIGH*
148.5MHz
Other
X
LOW
Input
Fixed – 27MHz
[01]
27MHz
74.25MHz
X
HIGH*
27MHz
X
LOW
74.25MHz
148.5MHz
X
LOW
148.5MHz
Other
X
LOW
Input
Fixed –
74.25MHz [10]
27MHz
74.25MHz
0
LOW
27MHz
0
HIGH*
74.25MHz
148.5MHz
0
LOW
148.5MHz
Other
0
LOW
Input
Fixed –
27MHz
X
LOW
27MHz
148.5MHz [11]
74.25MHz
X
LOW
74.25MHz
148.5MHz
X
HIGH*
148.5MHz
Other
X
LOW
Input
*NOTE: Although LOCK = HIGH under these conditions, the output clock will be a copy of the
selected input clock and will have the jitter of the input clock.
GS4915 ClockCleaner™
Data Sheet
39145 - 5
June 2009
19 of 27