
W149
Document #: 38-07176 Rev. *A
Page 11 of 16
AC Electrical Characteristics
TA = 0°C to +70°C; VDDQ3 = 3.3V±5%; VDDQ2 = 2.5V±5%; fXTL = 14.31818 MHz
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, CPU_F, CPU1 (Lump Capacitance Test Load = 20 pF)
Parameter
Description
Test Condition/Comments
CPU = 66.6 MHz
CPU = 100 MHz
Unit
Min.
Typ.
Max.
Min.
Typ.
Max.
tP
Period
Measured on rising edge at 1.25V
15
15.5
10
10.5
ns
tH
High Time
Duration of clock cycle above 2.4V, at
min. edge rate (1.5 V/ns)
5.6
3.3
ns
tL
Low Time
Duration of clock cycle below 0.4V, at
min. edge rate (1.5 V/ns)
5.3
3.1
ns
tR
Output Rise Edge Rate Measured from 0.4V to 2.4V
1.5
4
1.5
4
V/ns
tF
Output Fall Edge Rate
Measured from 2.4V to 0.4V
1.5
4
1.5
4
V/ns
tD
Duty Cycle
Measured on rising and falling edge at
1.5V, at min. edge rate (1.5 V/ns)
45
55
45
55
%
tJC
Jitter, Cycle-to-Cycle
Measured on rising edge at 1.25V. Max-
imum difference of cycle time between
two adjacent cycles.
250
250
ps
tSK
Output Skew
Measured on rising edge at 1.5V
175
175
ps
fST
Frequency Stabiliza-
tion from Power-up
(cold start)
Assumes full supply voltage reached
within 1 ms from power-up. Short cycles
exist prior to frequency stabilization.
33
ms
Zo
AC Output Impedance
Average value during switching transi-
tion. Used for determining series termi-
nation value.
20
20
Ω