W164G Cypress Semiconductor Corp., W164G Datasheet - Page 8

• Manufacturer Part Number: W164G
• Description: Spread Spectrum Desktop / Notebook System Frequency Generator
• Manufacturer: Cypress Semiconductor Corp.

DC Electrical Characteristics:
AC Electrical Characteristics
T
AC clock parameters are tested and guaranteed over stated operating conditions using the stated lump capacitive load at the
clock output; Spread Spectrum clocking is disabled.
CPU Clock Outputs, CPU0:1 (Lump Capacitance Test Load = 20 pF)
Notes:
Document #: 38-07169 Rev. *A
6.
7.
8.
Crystal Oscillator
V
C
C
Pin Capacitance/Inductance
C
C
L
Parameter
t
t
t
t
t
t
t
t
f
Z
A
P
H
L
R
F
D
JC
SK
ST
Parameter
IN
o
TH
LOAD
IN,X1
IN
OUT
= 0°C to +70°C, V
X1 input threshold voltage (typical) is V
The W164 contains an internal crystal load capacitor between pin X1 and ground and another between pin X2 and ground. Total load placed on crystal is 14 pF;
this includes typical stray capacitance of short PCB traces to crystal.
X1 input capacitance is applicable when driving X1 with an external clock source (X2 is left unconnected).
Period
High Time
Low Time
Output Rise Edge Rate Measured from 0.4V to 2.0V
Output Fall Edge Rate Measured from 2.0V to 0.4V
Duty Cycle
Jitter, Cycle-to-Cycle
Output Skew
Frequency Stabiliza-
tion from Power-up
(cold start)
AC Output Impedance Average value during switching transi-
X1 Input Threshold Voltage
Load Capacitance, as seen by
External Crystal
X1 Input Capacitance
Input Pin Capacitance
Output Pin Capacitance
Input Pin Inductance
Description
DDQ3
= 3.3V±5%,V
Description
[7]
DD
/2.
[8]
Measured on rising edge at 1.25V
Duration of clock cycle above 2.0V
Duration of clock cycle below 0.4V
Measured on rising and falling edge at
1.25V
Measured on rising edge at 1.25V. Max-
imum difference of cycle time between
two adjacent cycles.
Measured on rising edge at 1.25V
Assumes full supply voltage reached
within 1 ms from power-up. Short cycles
exist prior to frequency stabilization.
tion. Used for determining series termi-
nation value.
T
DDQ2
A
= 0°C to +70°C, V
[6]
Test Condition/Comments
= 2.5V± 5%, f
V
Pin X2 unconnected
Except X1 and X2
DDQ3
XTL
DDQ3
Test Condition
= 14.31818 MHz
= 3.3V
= 3.3V±5%, V
Min. Typ. Max. Min. Typ. Max.
DDQ2
CPU = 66.8 MHz
5.2
5.0
15
45
1
1
= 2.5V±5% (continued)
Min.
20
15.5
175
200
55
4
4
3
Typ.
1.65
13
26
3.0
2.8
CPU = 100 MHz
10
45
1
1
20
Max.
7
Page 8 of 12
10.5
250
175
55
4
4
3
W164
Unit
nH
pF
pF
pF
pF
V
V/ns
V/ns
Unit
ms
ns
ns
ns
ps
ps
%