W254B Datasheet, PDF (14/16 Pages) SpectraLinear Inc – 133MHz Spread Spectrum FTG for Mobile Pentium® III Platforms

W254B
Group Skew and Jitter Limits
Output Group
CPU
SDRAM
APIC
48MHz
3V66
PCI
REF
VCH_CLK
Pin-Pin Skew Max.
150 ps
250 ps
250 ps
N/A
175 ps
500 ps
N/A
N/A
Cycle-Cycle Jitter
250 ps
250 ps
500 ps
500 ps
500 ps
500 ps
1000 ps
250 ps
Duty Cycle
45/55
45/55
45/55
45/55
45/55
45/55
45/55
45/55
Nom Vdd
2.5V
3.3V
2.5V
3.3V
3.3V
3.3V
3.3V
3.3V
Output
Buffer
Test Point
Clock Output Wave
2.0
1.25
2.5V Clocking
Interface
0.4
T_RISE
T_HIGH
T_FALL
Test Load
T_PERIOD
Duty Cycle
T_LOW
T_HIGH
T_PERIOD
Duty Cycle
2.4
3.3V Clocking ^1.5
Interface ^0.4
T_RISE
T_FALL
T_LOW
Figure 10. Output Buffer
Skew, Jitter
Measure Point
1.25V
1.5V
1.25V
1.5V
1.5V
1.5V
1.5V
1.5V
Rev 1.0, November 20, 2006
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