Cypress CY25818 User Manual

Spread Spectrum Clock Generator

CY25818/19

Cypress Semiconductor Corporation

•

198 Champion Court

•

San Jose

,

CA 95134-1709

•

408-943-2600

Document #: 38-07362 Rev. *B

Revised April 11, 2006

Features

• 8- to 32-MHz input frequency range

• CY25818: 8–16 MHz

• CY25819: 16–32 MHz

• Separate modulated and unmodulated clocks

• Accepts clock, crystal, and resonator inputs

• Down spread modulation

• Power-down function

• Low-power dissipation

— CY25818 = 33 mW-typ @ 8 MHz

— CY25818 = 56 mW-typ @ 16 MHz

— CY25819 = 36 mW-typ @ 16 MHz

— CY25819 = 63 mW-typ @ 32 MHz

• Low cycle-to-cycle jitter

— SSCLK = 250 ps-typ

— REFOUT = 275 ps-typ

• Available in 8-pin (150-mil) SOIC package

Applications

• Printers and MFPs

• LCD panels and notebook PCs

• Digital copiers

• PDAs

• Automotive

• CD-ROM, VCD, and DVD

• Networking and LAN/WAN

• Scanners

• Modems

• Embedded digital systems

Benefits

• Peak electromagnetic interference (EMI) reduction by

8–16 dB

• Fast time to market

• Cost reduction

REFERENCE

DIVIDER

PD and

CP

LF

VCO

DIVIDER

and

MUX

INPUT

DECODER

1

8

300K

MODULATION

CONTROL

3

6

S0 PD#

XIN/CLKIN

XOUT

VDD

7

VSS

2

4

SSCLK

5

REFCLK

VCO

COUNTER

2

1

3

4

8

7

6

5

XIN/CLKIN

Vss

S0

SSCLK

XOUT

Vdd

PD#

REFCLK

CY25818
CY25819

8 Pin SOIC

8-pin SOIC

Block Diagram

Pin Configuration