AMERICAN MICROSYSTEMS, INC.

April 2000

American Microsystems, Inc. reserves the right to change the detail specifications as may be required to permit improvements in the design of its products.

4.24.00

FS6128-04 / FS6128-05 / FS6128-06

FS6128-04 / FS6128-05 / FS6128-06

FS6128-04 / FS6128-05 / FS6128-06

FS6128-04 / FS6128-05 / FS6128-06

PLL Clock Generator IC with VCXO

PLL Clock Generator IC with VCXO

PLL Clock Generator IC with VCXO

PLL Clock Generator IC with VCXO

ISO9001

ISO9001

ISO9001

ISO9001

1.0

Features

•

Phase-locked loop (PLL) device synthesizes output

clock frequency from crystal oscillator or external ref-

erence clock

•

On-chip tunable voltage-controlled crystal oscillator

(VCXO) allows precise system frequency tuning

•

Typically used for generation of MPEG-2 decoder

clock

•

3.3V supply voltage

•

Very low phase noise PLL

•

Use with “pullable” 14pF crystals – no external pad-

ding capacitors required

•

Small circuit board footprint (8-pin 0.150

″ SOIC)

•

Custom frequency selections available - contact your

local AMI Sales Representative for more information

Figure 1: Pin Configuration

1

8

2

3

4

7

6

5

XIN

VDD

XTUNE

VSS

VSS

n/c

CLK

XOUT

8-pin (0.150

″) SOIC

2.0

Description

The FS6128 is a monolithic CMOS clock generator IC

designed to minimize cost and component count in digital

video/audio systems.

At the core of the FS6128 is circuitry that implements a

voltage-controlled crystal oscillator (VCXO) when an ex-

ternal resonator (nominally 13.5MHz) is attached. The

VCXO allows device frequencies to be precisely adjusted

for use in systems that have frequency matching re-

quirements, such as digital satellite receivers.

A high-resolution phase-locked loop generates an output

clock (CLK) through a post-divider. The CLK frequency is

ratiometrically derived from the VCXO frequency. The

locking of the CLK frequency to other system reference

frequencies can eliminate unpredictable artifacts in video

systems and reduce electromagnetic interference (EMI)

due to frequency harmonic stacking.

Table 1: Crystal / Output Frequencies

DEVICE

CLK (MHz)

FS6128-04

13.500

27.000

FS6128-05

13.500

13.500

FS6128-06

13.500

54.000

NOTE: Contact AMI for custom PLL frequencies

Figure 2: Block Diagram

VCXO

FS6128-04

FS6128-05

FS6128-06

PLL

XOUT

XIN

CLK

XTUNE

DIVIDER