ASM3P2187A_1 Datasheet, PDF (1/9 Pages) PulseCore Semiconductor – Spread Spectrum Clock Generator for Mobile Applications

May 2008
rev 0.2
ASM3P2187A/B
Spread Spectrum Clock Generator for Mobile Applications
Features
• Generates a 4X EMI optimized clock signal at the
Output.
• Input frequency : 12.5MHz to 20MHz
• 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
Product Description
The ASM3P2187A/B is a versatile spread spectrum
frequency modulator designed specifically for a wide
range of clock frequencies. The ASM3P2187A/B reduces
electromagnetic interference (EMI) at the clock source,
allowing system wide reduction of EMI of all clock
dependent signals. The ASM3P2187A/B allows
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
CLKIN/XIN
XOUT
Crystal
Oscillator
SEL SSON/PDB
VDD
Frequency
Divider
Feedback
Divider
Modulation
Phase
Detector
Loop
Filter
PLL
VCO
Output
Divider
ModOUT
REFOUT
VSS
PulseCore Semiconductor Corporation
1715 S. Bascom Ave Suite 200, Campbell, CA 95008 • Tel: [phone] • Fax: [phone]
www.pulsecoresemi.com
Notice: The information in this document is subject to change without notice.