English
Language : 

W159 Datasheet, PDF (9/11 Pages) Cypress Semiconductor – Spread Spectrum System FTG for SMP Systems
W159
CPUdiv2 Clock Outputs, CPUdiv2_0:1 (Lump Capacitance Test Load = 20 pF)
CPU = 133 MHz CPU = 100 MHz
Parameter
Description
Test Condition/Comments
Min. Typ. Max. Min. Typ. Max. Unit
tP
Period
Measured on rising edge at 1.25V
15
15.3 20
20.4 ns
tH
High Time
Duration of clock cycle above 2.0V
5.25
7.5
ns
tL
Low Time
Duration of clock cycle below 0.4V
5.05
7.3
ns
tR
Output Rise Edge Rate Measured from 0.4V to 2.0V
1
41
4 V/ns
tF
Output Fall Edge Rate Measured from 2.0V to 0.4V
1
41
4 V/ns
tD
Duty Cycle
Measured on rising and falling edge at 45
1.25V
55 45
55 %
tJC
Jitter, Cycle-to-Cycle Measured on rising edge at 1.25V. Max-
250
imum difference of cycle time between
two adjacent cycles.
250 ps
tSK
Output Skew
Measured on rising edge at 1.25V
175
175 ps
fST
Frequency Stabiliza- Assumes full supply voltage reached
3
tion from Power-up within 1 ms from power-up. Short cycles
(cold start)
exist prior to frequency stabilization.
3 ms
Zo
AC Output Impedance Average value during switching transi-
20
tion. Used for determining series termi-
nation value.
20
Ω
APIC Clock Outputs, APIC0:2 (Lump Capacitance Test Load = 20 pF)
Parameter
Description
Test Condition/Comments
Min
f
Frequency
Note 21
tR
Output Rise Edge Rate Measured from 0.4V to 2.0V
1
tF
Output Fall Edge Rate
Measured from 2.0V to 0.4V
1
tD
Duty Cycle
Measured on rising and falling edge at 1.25V
45
fST
Frequency Stabilization Assumes full supply voltage reached within
from Power-up (cold start) 1 ms from power-up. Short cycles exist prior to
frequency stabilization.
Zo
AC Output Impedance
Average value during switching transition. Used
for determining series termination value.
Note:
21. APIC clock is CPU/8 for CPU = 133 MHz and CPU/6 for CPU = 100 MHz.
Typ Max
16.67
4
4
55
3
20
Unit
MHz
V/ns
V/ns
%
ms
Ω
Ordering Information
Ordering Code
Package
Name
W159
H
Package Type
56-pin SSOP (300 mils)
Intel is a registered trademark of Intel Corporation.
Document #: 38-07163 Rev. *A
Page 9 of 11