© Semiconductor Components Industries, LLC, 2015

February, 2015 − Rev. 0

1

Publication Order Number:

PCS3P25811/D

PCS3P25811,

PCS3P25812,

PCS3P25814

Spread Spectrum Clock

Generator

Product Description

The PCS3P25811/12/14 devices are versatile spread spectrum

frequency modulators designed specifically for a wide range of input

clock frequencies from 4 MHz to 32 MHz.

The PCS3P25811/12/14 reduce electromagnetic interference (EMI)

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

stream clock and data dependent signals. It 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 PCS3P25811/12/14 can generate an EMI reduced clock from

crystal, ceramic resonator, or system clock.

The PCS3P25811/12/14 modulate 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’.

The PCS3P25811/12/14 use the most efficient and optimized

modulation profile approved by the FCC and is implemented in a

proprietary all−digital method.

The PCS3P25811/12/14 have 2 pins S0 and S1 to control the

selection of Center Spread, Down Spread and No−Spread functions.

Additionally there is a 3 level logic contol FSEL, for selecting one of

the three different frequency ranges within the operating frequency

range. Refer Input/Output Frequency Range Selection Table.

The PCS3P25811/12/14 operate from a 2.8 V to 3.6 V supply and

are available in 8 pin SOIC, and 8L 2 mm x 2 mm WDFN packages.

Applications

The PCS3P25811/12/14 are targeted towards EMI

management in applications such as LCD Panels, MFPs,

Digital copiers, Networking, PC peripheral devices,

consumer electronics, and embedded controller systems.

Features

4x(PCS3P25814) Low EMI Spread Spectrum Clock of

the Input Frequency

PCS3P25812: 8 MHz − 64 MHz

PCS3P25814: 16 MHz − 128 MHz

Spread

3.3 V: 24 mW (typ) @ 12 MHz

3.3 V: 30 mW (typ) @ 24 MHz

CY25811, CY25812 and CY25814

Packages

and are RoHS Compliant

www.onsemi.com

PIN CONFIGURATION

See detailed ordering and shipping information in the package

dimensions section on page 9 of this data sheet.

ORDERING INFORMATION

XIN / CLKIN

VSS

1

2

3

4

5

6

7

8

S0

ModOUT

VDD

XOUT

S1

FSEL

PCS3P25811

PCS3P25812

PCS3P25814

1

8

SOIC−8 NB

CASE 751

WDFN8 2x2, 0.5P

CASE 511AQ

1