March 2007

ASM3P2855B

rev 0.2

Notice: The information in this document is subject to change without notice.

Custom Clock Generator for Fax System

4 of 7

AC Electrical Characteristics

Symbol

Parameter

Min

Typ

Max

Unit

XIN / CLKIN

Input frequency

24

MHz

At Pins 7,8,9,10,11,13,14,15

50

At Pin 12

24

Output frequency

At Pin 16

19.52

MHz

Output rise time (measured from 0.8 to 2.0V)

0.9

nS

Output fall time (measured at 2.0V to 0.8V)

0.7

nS

Jitter (Cycle to cycle)

250

pS

Output duty cycle

40

50

60

%

Typical Crystal Oscillator Circuit

Typical Crystal Specifications

Fundamental AT cut parallel resonant crystal

Nominal frequency

24MHz

Frequency tolerance

± 50 ppm or better at 25°C

Operating temperature range

-25°C to +85°C

Storage temperature

-40°C to +85°C

Load capacitance

18pF

Shunt capacitance

7pF maximum

ESR

25 Ω

R1 = 510Ω

C1

C2

Crystal