© Semiconductor Components Industries, LLC, 2011

August, 2011 − Rev. P2

1

Publication Order Number:

ASM3P2107A/D

ASM3P2107A

Product Preview

Peak EMI Reducing

Solution

Description

The ASM3P2107A is a versatile spread spectrum frequency

modulator designed specifically for input clock frequencies from

12 MHz to 22 MHz. The ASM3P2107A can generate an EMI reduced

clock from crystal, ceramic resonator, or system clock.

The ASM3P2107A reduces electromagnetic interference (EMI) at

the clock source, allowing system wide reduction of EMI of down

stream clock and data dependent signals. The ASM3P2107A allows

significant system cost savings by reducing the number of circuit

board layers ferrite beads, shielding and other passive components that

are traditionally required to pass EMI regulations.

The ASM3P2107A uses the most efficient and optimized

modulation profile approved by the FCC and is implemented in a

proprietary all digital method.

The ASM3P2107A modulates the output of a single PLL in order to

“spread” the bandwidth of a synthesized clock, and more importantly,

decreases the peak amplitudes of its harmonics. This results in

significantly lower system EMI compared to the typical narrow band

signal produced by oscillators and most frequency generators.

Lowering EMI by increasing a signal’s bandwidth is called ‘spread

spectrum clock generation.’

Applications

The ASM3P2107A is targeted towards EMI management for high

speed digital applications such as PC peripheral devices, consumer

electronics and embedded controller systems.

Features

Frequency

Space

This document contains information on a product under development. ON Semiconductor

reserves the right to change or discontinue this product without notice.

http://onsemi.com

SOIC−8

S SUFFIX

CASE 751BD

PIN CONFIGURATION

(Top View)

See detailed ordering and shipping information in the package

dimensions section on page 6 of this data sheet.

ORDERING INFORMATION

NC

NC

VDD

CLOCKOUT

XOUT

GND

XIN/CLKIN

1

NC

TSSOP−8

T SUFFIX

CASE 948AL