W137

Rev 1.0, November 24, 2006

Page 6 of 8

AC Electrical Characteristics

AC clock parameters are tested and guaranteed over stated operating conditions using the stated lump capacitive load at the

clock output.

Pin Capacitance/Inductance

Input Pin Capacitance

Except X1 and X2

5

pF

Output Pin Capacitance

6

pF

Input Pin Inductance

7

nH

Parameter

Description

Test Condition

Min.

Typ.

Max.

Unit

Notes:

4. The W137 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.

5. X1 input capacitance is applicable when driving X1 with an external clock source (X2 is left unconnected).

CPU Clock Outputs, CPU0:1 (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.

Period

Measured on rising edge at 1.25V

15

15.5

10

10.5

ns

High Time

Duration of clock cycle above 2.0V

5.2

3.0

ns

Low Time

Duration of clock cycle below 0.4V

5.0

2.8

ns

Output Rise Edge Rate Measured from 0.4V to 2.0V

1

4

1

4

V/ns

Output Fall Edge Rate Measured from 2.0V to 0.4V

1

4

1

4

V/ns

Duty Cycle

Measured on rising and falling edge at

1.25V

45

55

45

55

%

Jitter, Cycle-to-Cycle

Measured on rising edge at 1.25V.

Maximum difference of cycle time

between two adjacent cycles.

200

200

ps

Output Skew

Measured on rising edge at 1.25V

175

175

ps

Frequency Stabili-

zation from Power-up

(cold start)

Assumes full supply voltage reached

within 1 ms from power-up. Short cycles

exist prior to frequency stabilization.

3

3

ms

AC Output Impedance Average value during switching

transition. Used for determining series

termination value.

13.5

13.5