1

SY89429A

Micrel, Inc.

26

27

28

1

2

3

4

18

17

16

15

14

13

12

25 24 23 22 21 20 19

5

6

7

8

9 10 11

VCC_QUIET

XTAL1

S_CLOCK

S_DATA

LOOP_REF

S_LOAD

LOOP_FILTER

M[8]

M[4]

M[7]

M[5]

N[1]

M[6]

N[0]

PLCC

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The SY89429A is a general purpose, synthesized clock

source targeting applications that require both serial and

parallel interfaces. Its internal VCO will operate over a range

offrequenciesfrom400MHzto 800MHz.The differential PECL

output can be configured to be the VCO frequency divided by

2, 4, 8 or 16. With the output configured to divide the VCO

frequency by 2, and with a 16MHz external quartz crystal used

to provide the reference frequency, the output frequency can

be specified in 1MHz steps.

FEATURES

DESCRIPTION

PROGRAMMABLE

FREQUENCY SYNTHESIZER

(25MHz to 400MHz)

n

Improved jitter performance over SY89429

n

25MHz to 400MHz differential PECL outputs

n

±25ps peak-to-peak output jitter

n

Minimal frequency over-shoot

n

Synthesized architecture

n

Serial 3 wire interface

n

Parallel interface for power-on

n

Internal quartz reference oscillator driven by quartz

crystal or PECL source

n

PECL output can operate with either +3.3V or +5V

VCC_OUT power supply

n

Externalloopfilteroptimizesperformance/cost

n

Applications note (AN-06) for ease of design-ins

n

Available in PLCC and SOIC 28-pin packages

PIN CONFIGURATION

APPLICATIONS

n

Workstations

n

Advanced communications

n

High end consumer

n

High-performance computing

n

RISC CPU clock

n

Graphics pixel clock

n

Test equipment

n

Other high-performance processor-based

applications

GND (TTL)

FOUT

17

12

N[1]

VCC_OUT

18

11

VCC (TTL)

GND

15

14

TEST

/FOUT

16

13

1

M[0]

M[1]

M[2]

M[3]

M[4]

M[5]

M[6]

M[7]

M[8]

N[0]

28 /P_LOAD

VCC1

XTAL2

XTAL1

LOOP_REF

LOOP_FILTER

VCC_QUIET

S_LOAD

S_DATA

S_CLOCK

27

26

25

24

23

22

21

20

19

2

3

4

5

6

7

8

9

10

SOIC

TOP VIEW

Rev.: K

Amendment: /0

Issue Date: July 2009

Precision Edge is a registered trademark of Micrel, Inc.

SY89429A