May 2008
rev 0.2
ASM3P2187A/B
Spread Spectrum Clock Generator for Mobile Applications
Features
•
Generates a 4X EMI optimized clock signal at the
Product Description
The ASM3P2187A/B is a versatile spread spectrum
frequency modulator designed specifically for a wide
: 12.5MHz to 20MHz
range of clock frequencies. The ASM3P2187A/B reduces
electromagnetic interference (EMI) at the clock source,
allowing system wide reduction of EMI of
dependent
signals.
The
ASM3P2187A/B
all clock
allows
Output.
•
Input frequency
•
Output frequency : 50MHz to 80MHz
•
SSON/PDB option
•
Selectable Centre Spread :
± 0.5%, ± 1.0%
•
Low power CMOS design
•
Supply Voltage : 3.3V ± 0.3V
•
Industrial Temperature range
•
8-pin TSSOP Package
•
Drop-in replacement for MB88155-412 Device
significant system cost savings by reducing the number of
circuit board layers ferrite beads,
shielding that are
traditionally required to pass EMI regulations.
ASM3P2187A device has an option of Spread ON/OFF
and ASM3P2187B device has Powerdown option
Application
The ASM3P2187A/B is targeted towards mobile phones,
mobile audio players and PDAs.
Block Diagram
SEL SSON/PDB
VDD
PLL
Modulation
CLKIN/XIN
XOUT
Crystal
Oscillator
Frequency
Divider
Feedback
Divider
Phase
Detector
Loop
Filter
VCO
Output
Divider
ModOUT
REFOUT
VSS
PulseCore Semiconductor Corporation
1715 S. Bascom Ave Suite 200, Campbell, CA 95008
•
Tel: 408-879-9077
•
Fax: 408-879-9018
www.pulsecoresemi.com
Notice: The information in this document is subject to change without notice.