PLL Clock

Synthesis and

Spread Spectrum

Circuitry

MK1704A

Low EMI Clock Generator

MDS 1704A B

1

Revision 062599

Printed 11/15/00

MicroClock Division of ICS • 525 Race Street • San Jose • CA • 95126•(408)295-9800tel•(408)295-9818fax

I C R O

The MK1704A is an upgraded version of the

MK1704 and is recommended for all new designs.

It offers more reduction in the frequency

amplitude peaks, and will support frequencies up

to 140 MHz.

The MK1704A generates a low EMI output clock

from a clock input. The part is designed to dither

the LCD interface clock or other clocks for flat

panel graphics controllers. The MK1704A uses

ICS/MicroClock’s proprietary mixture of analog

and digital Phase-Locked Loop (PLL) technology

to synthesize the frequency, and our patented

technique to spread the frequency spectrum of the

output, thereby reducing the frequency amplitude

peaks by several dB.

We offer many other clocks for computers and

computer peripherals. Consult us when you need

to remove crystals and oscillators from your board.

Block Diagram

Description

Features

• Packaged in 8 pin SOIC

• Provides a spread spectrum output clock

• Supports leading flat panel controllers

• Accepts a clock input, provides same frequency

dithered output

• Optimized for higher resolutions that require up

to 140 MHz, as well as 40 MHz (SVGA) and

65 MHz (XVGA) clocks

• Peak reduction by 7dB - 14 dB typical on 3rd-

19th odd harmonics

• Low EMI feature can be disabled

• 3.3 V or 5 V ±10% supply voltage

• Advanced, low power CMOS process

• See the MK1714-01 for a multiplier with low

EMI which can operate from a crystal

Crystal

Oscillator

VDD GND

S1

Output

Buffer

Clock Out

Input Clock

Low EMI

Enable

S0