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MK2771-16

VCXOandSet-TopClockSource

ICROCLOCK

PAGE

1

MDS2771-16C

Revision102099

Printed11/16/00

Description Features

TheMK2771-16isalowcost,lowjitter,highperformanceVCXOandclocksynthesizerdesignedforset-topboxes.Theon-chipVoltageControlledCrystalOscillatoracceptsa0to3Vinputvoltagetocausetheoutputclockstovaryby

±100ppm.UsingICS/MicroClock’spatentedVCXOandogPhase-LockedLoop(PLL)techniques,thedeviceusesaninexpensive

13.5MHzcrystalinputtoproducemultipleoutputclocksincludingaselectableprocessorclock,aselectableaudioclock,twocommunicationsclocks,a13.5MHzclock,andthree27MHzclocks.Allclocksarefrequencylockedtothe27.00MHzoutput(andtoeachother)withzeroppmerror,soanyoutputcanbeusedastheVCXOoutput.

Packagedin28pinSSOP(QSOP)

On-chippatentedVCXOwithpullrangeof200ppm(minimum)

VCXOtuningvoltageof0to3V

Processorfrequencyinclude16.66,20,25,32,40,

and50MHz

Audioclockssupport32kHz,44.1kHz,48kHzand96kHzsamplingrates

Zeroppmsynthesiserrorinallclocks(allexactlytrack27MHzVCXO)

Usesaninexpensive13.5MHzcrystal

FullCMOSoutputswingswith25mAoutputdrivecapabilityatTTLlevels

Advanced,lowpower,sub-micronCMOSprocess

5Voperatingvoltagewith3.3VcapableI/O

BlockDiagram

VDD5 GND

VDDIO

3

AS2:0

2

PS1,PS0

2

CS1,CS0

VIN

ACLKPCLK

OutputBuffer

OutputBuffer

OutputBuffer

CCLK1

x2PLL

VoltageControlledCrystalOscillator

OutputBuffer

CCLK2

PLL

ClockSynthesisCircuitry

13.5MHz X1

pullablecrystal

÷2

X2

3

OutputBuffers

27.000MHz

OutputBuffer

13.500MHz

PinAssignment

10

11

12

13

14

28

27

26

25

24

23

22

21

20

19

18

17

16

PS0X2GND

X1VDD5VINVDDIOVDD5

CS1GNDGNDPCLKCCLK2ACLK

PS1

PS0

PCLK

0

0

50

0

1

16.667

M

0

25

M

VDD5=5V±10%

AS1AS0CS027MGND27MVDD5AS2GNDGND27MCCLK1PS113.5M

AudioClock(MHz)

AS2

AS1

AS0

ACLK

0

0

0

8.192

0

0

1

11.2896

0

1

0

12.288

0

1

1

5.6448

1

0

0

18.432

1

0

1

16.9344

1

1

0

49.152

1

1

1

24.576

0=connectdirectlytoGND

M=leaveunconnected(floating)1=connectdirectlytoVDDIO

CommunicationsClocks(MHz)

CS1

CS0

CCLK1

CCLK2

0

0

Low

33.333

0

1

Low

24.576

1

0

11.0592

18.432

1

1

11.0592

3.6864

ProcessorClock(MHz)

VDDIO=3.3V±10%VIN=0to3.0V(3.3VOK)

Number

Name

Type

Description

1

PS0

I

ProcessorClockSelect0.SelectsPCLKfrequency.Seetableabove.Internalpull-up.

2

X2

XO

Crystalconnection.Connecttoapullable13.5MHzcrystal.

3,10,11

GND

P

Connecttoground.

4

X1

XI

Crystalconnection.Connecttoapullable13.5MHzcrystal.

5,8,22

VDD5

P

Connectto+5V.

6

VIN

I

VoltageInputtoVCXO.Zeroto3VsignalwhichcontrolsthefrequencyoftheVCXO.

7

VDDIO

P

Connectto+3.3Vor+5V.Amplitudeofinputsandoutputswillmatchthis.

9

CS1

I

Communicationsclockselectpin1.SelectsCCLK1and2pertableabove.Internalpull-up.

12

PCLK

O

ProcessorClockoutput.DeterminedbystatusofPS1,PS0.

13

CCLK2

O

CommunicationsClockoutput2determinedbystatusofCS1,CS0pertableabove.

14

ACLK

O

AudioClockOutput.DeterminedbystatusofAS2:0pertableabove.

15

13.5M

O

13.50MHzVCXOclockoutput.

16

PS1

TI

ProcessorClockSelect1.SelectsPCLKfrequency.Seetableabove.Self-biasedtoM.

17

CCLK1

O

CommunicationsClockoutput1determinedbystatusofCS1,CS0pertableabove.

18,23,25

27M

O

27.00MHzVCXOclockoutput.

19,20,24

GND

P

Connecttoground.

21

AS2

I

AudioClockSelect2.SelectsACLKonpin14pertableabove.Internalpull-up.

26

CS0

I

Communicationsclocksselectpin0.SelectsCCLK1and2pertableabove.Internalpull-up.

27

AS0

I

AudioClockSelect0.SelectsACLKonpin14.Seetableabove.Internalpull-up.

28

AS1

I

AudioClockSelect1.SelectsACLKonpin14.Seetableabove.Internalpull-up.

Key:I=Input;TI=Tri-levelinput;O=output;P=powersupplyconnection;XI,XO=crystalconnections

MK2771-16

VCXOandSet-TopClockSource

ICROCLOCK

ElectricalSpecifications

Parameter

Conditions

Minimum

Typical

um

Units

ABSOLUTEUMRATINGS(note1)

Supplyvoltage,VDD

ReferencedtoGND

7

V

InputsandClockOutputs

ReferencedtoGND

-0.5

VDD+0.5

V

AmbientOperatingTemperature

0

70

°C

SolderingTemperature

Maxof10seconds

260

°C

Storagetemperature

-65

150

°C

DCCHARACTERISTICS(VDD=5.0Vunlessnoted)

OperatingVoltage,VDD

4.75

5.25

V

OperatingVoltage,VDDIO

forallinputs/outputs

3.00

5.25

V

InputHighVoltage,VIH,X1pinonly

3.5

2.5

V

InputLowVoltage,VIL,X1pinonly

2.5

1.5

V

InputHighVoltage,VIH(exceptPS1)

2

V

InputLowVoltage,VIL(exceptPS1)

0.8

V

InputHighVoltage,VIH,PS1only

VDD-0.5

V

InputLowVoltage,VIL,PS1only

0.5

V

OutputHighVoltage,VOH

IOH=-25mA

2.4

V

OutputLowVoltage,VOL

IOL=25mA

0.4

V

OutputHighVoltage,VOH,CMOSlevel

IOH=-8mA

VDD-0.4

V

OperatingSupplyCurrent,IDD5

NoLoad,note2

42

mA

OperatingSupplyCurrent,IDDIO

NoLoad,VDDIO=3.3V

19

mA

ShortCircuitCurrent

Eachoutput

±100

mA

InputCapacitance

7

pF

Frequencysynthesiserror

Allclocks

0

ppm

VIN,VCXOcontrolvoltage

0

3

V

ACCHARACTERISTICS(VDD=5.0Vunlessnoted)

InputFrequency

13.500000

MHz

OutputClockRiseTime

0.8to2.0V

1.5

ns

OutputClockFallTime

2.0to0.8V

1.5

ns

OutputClockDutyCycle

At1.4V

40

60

%

umAbsoluteJitter,shortterm

300

ps

27MHzoutputpullability,note3

0VVIN3V

±100

±140

ppm

Notes: 1.StressesbeyondthoselistedunderAbsolute umRatingscouldcausepermanentdamagetothedevice.ProlongedexposuretolevelsabovetheoperatinglimitsbutbelowtheAbsolute umsmayaffectdevicereliability.

WithallclocksathighestMHz.

WithapullablecrystalthatconformstoICS’specifications:

Correlation(load)capacitance

14pF

C0/C1

240

um

ESR

25

um

InitialAccuracy

±20ppm

AgingandTempstability

±50ppm

OperatingTemperature

0to70°C

MDS2771-16C 3 Revision102099 Printed11/16/00

MK2771-16

VCXOandSet-TopClockSource

ICROCLOCK

ExternalComponents

TheMK2771-16requiresaminimumnumberofexternalcomponentsforproperoperation.Usealowinductancegroundne,connectallGNDstothis.Connect0.01μFdecouplingcapsonpins5,7,8and22directlytotheground ne,as

closetotheMK2771-16aspossible.Aseriesterminationresistorof33maybeusedforeachclockoutput.The13.500

MHzcrystalmustbeconnectedasclosetothechipaspossible.Thecrystalshouldbeaparallelmode,pullable,withloadcapacitanceof14pF.ConsultICS/MicroClockfullspecifications.PleaseobeyApplicationNoteMAN05forpullablecrystallayoutinfoexceptforthefollowing:theMK2771-16introducesaGNDpin(pin#3)betweenthepullablecrystalpins.Thisgroundshouldbebroughtinstraightfromtherightsideunderneaththedevice.

PackageOutlineandPackageDimensions

(Forcurrentdimensionalspecifications,seeJEDECPublicationNo.95.)

28pinSSOP

Inch

es

Millim

eters

Symbol

Min

Max

Min

Max

A

0.053

0.069

1.35

1.75

A1

0.004

0.010

0.102

0.254

B

0.008

0.012

0.203

0.305

C

0.007

0.010

0.191

0.254

D

0.386

0.394

9.804

10.008

E

0.150

0.157

3.810

3.988

e

.025B

SC

0.635

SC

H

0.228

0.244

5.791

6.198

L

0.016

0.050

0.406

1.270

E H

D

A1 C A

e B L

OrderingInformation

Part/OrderNumber

Marking

Shippackaging

Package

Temperature

MK2771-16R

MK2771-16R

tubes

28pinSSOP(QSOP)

0-70°C

MK2771-16RTR

MK2771-16R

tapeandreel

28pinSSOP(QSOP)

0-70