© Semiconductor Components Industries, LLC, 2011

August, 2011 − Rev. P2

1

Publication Order Number:

ASM3P1819N/D

ASM3P1819N

Product Preview

Low Power Mobile VGA EMI

Reduction IC

Description

The ASM3P1819N is a versatile spread spectrum frequency

modulator designed specifically for a wide range of input clock

frequencies from 20 to 40 MHz. The ASM3P1819N can generate an

EMI reduced clock from crystal, ceramic resonator, or system clock.

The ASM3P1819N reduces electromagnetic interference (EMI) at

the clock source, allowing a system wide EMI reduction for all the

down stream clocks and data dependent signals. The ASM3P1819N

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 ASM3P1819N modulates the output of a single PLL in order to

“spread” the bandwidth of a synthesized clock, thereby decreasing the

peak amplitude of its harmonics. This results in a significantly lower

system EMI compared to the typical narrow band signal produced by

oscillators and most clock generators.

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

spectrum clock generation”. The ASM3P1819N uses the most

efficient and optimized modulation profile approved by the FCC and

is implemented by using a proprietary all digital method.

Applications

The ASM3P1819N is targeted towards EMI management for

memory and LVDS interfaces in mobile graphic chipsets and

high−speed digital applications such as PC peripheral devices,

consumer electronics and embedded controller system.

Features

Reference Clock of the Input Frequency

Applications

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

XOUT

VDD

PD#

REF

VSS

NC

XIN

1

ModOUT

TSSOP−8

T SUFFIX

CASE 948AL