PLL702-05

Low EMI Peripheral Clock Generator for Notebook

47745 Fremont Blvd., Fremont, California 94538 Tel (510) 492-0990 Fax (510) 492-0991

www.phaselink.com

Rev 08/12/04 Page 1

FEATURES

• Single Low EMI IC to replace multiple crystals and

oscillators on Notebooks (27MHz, 14.318MHz,

24.576MHz, 25MHz).

• Selectable crystal input: 24.576MHz or 14.318MHz

(accuracy requirement +/- 20ppm)

• Less than 10ppm Frequency Synthesis error, meeting

AC97, IEEE1394, IEEE802 frequency precision

specification.

• 27MHz clock with 2 levels of Selectable Spread

Spectrum modulation +/- 0.5% and +/- 0.75% center.

• 25MHz clock with double drive strength (Ethernet PHY

and MAC).

• 24.576MHz clocks for Audio Codec and IEEE1394.

• Available in 8-Pin SOIC.

Table 1. SPREAD SPECTRUM SELECTION

SST0

SST Modulation only on

27MHz. (pin 7)

1

+/- 0.75 %

0

+/- 0.5 %

M

SST OFF (Default)

Notes: M = Do not connect. 1 = Pulled up. 0 = Pulled down.

BLOCK DIAGRAM

Note : Only 27MHz output is modulated for low EMI via Spread

Spectrum.

PIN ASSIGNMENT

POWER GROUPS

• VDD – VSS: XIN, XOUT, analog core, digital part ,

27MHz., 24.576MHz and 25MHz.

Table 2. CRYSTAL SELECTION TABLE

Crystal Input

XTAL_SEL

Pin 7

24.576MHz

0

27MHz

14.318MHz

1

14.318MHz

1

2

3

4

5

6

7

8

VDD

XIN

XOUT

VSS

25MHzx2

Note: 25MHzx2: double drive strength

*: Bi-directional pin

Ω)

VSS

SST(0)

PLL2

25MHz

27_14.318MHz

XTAL

OSC

XIN

XOUT

PLL

SST

XTAL_SEL

24.576MHz