IDT ICS8440258AK-46, ICS8440258AK-46LF Schematic [ru]

PRELIMINARY

FEMTOCLOCK™ CRYSTAL/LVCMOS-TO­LVDS/LVCMOS FREQUENCY SYNTHESIZER

GENERAL DESCRIPTION

ICS

HiPerClockS™

will generate both 125MHz and 25MHz clocks with mixed
LVDS and LVCMOS/LVTTL output logic. The ICS8440258-46
uses IDT’s 3
and can achieve <1ps typical rms phase jitter, easily meeting
Ethernet jitter requirements. The ICS8440258-46 is packaged
in a small, 5mm x 5mm VFQFN package.

The ICS8440258-46 is an 8 output synthesizer
optimized to generate Ethernet clocks and a
member of the HiPerClockS™ family of high
performance clock solutions from IDT. Using a
25MHz, 18pF parallel resonant crystal, the device

rd

generations low phase noise VCO technology

FEATURES

• Four differential LVDS outputs at 125MHz

• Selectable crystal oscillator interface or LVCMOS/LVTTL

• VCO range: 490MHz - 680MHz

• RMS phase jitter @ 125MHz, using a 25MHz crystal

• Full 2.5V operating supply

• 0°C to 70°C ambient operating temperature

• Available in both standard (RoHS 5) and lead-free (RoHS6)

PIN ASSIGNMENT

BLOCK DIAGRAM

Pulldown

MR

nPLL_SEL

XTAL_IN

XTAL_OUT

REF_CLK

nXTAL_SEL

Pulldown

25MHz

OSC

Pulldown

Pulldown

0

1

÷5

Phase

Detector

VCO

490-680MHz

0

1

÷25

ICS8440258-46

Two LVCMOS/LVTTL single-ended outputs at 125MHz
Two LVCMOS/LVTTL single-ended outputs at 25MHz

single-ended input

(1.875MHz - 20MHz): 0.34ps (typical)

packages

Q0

nQ0

Q1

nQ1

Q2

nQ2

Q3

nQ3

Q4

Q5

Q0

nQ0

GND

Q1

nQ1

V

Q2

nQ2

1

2

3

4

5

DD

6

7

8

nXTAL_SEL

XTAL_OUT

XTAL_IN

32 31 30 29 28 27 26 25

REF_CLK

MR

nPLL_SEL

V

DD

ICS8440258-46

32-Lead VFQFN

5mm x 5mm x 0.75mm

package body

K Package

Top View

9 10 11 12 13 14 15 16

DD

Q3

nQ3

Q4

V

GND

Q5

DDO1

V

VDDA

24

23

22

21

20

19

18

17

GND

nc

nc

nc

GND

Q7

V

DDO2

Q6

GND

Q6

Q7

The Preliminary Information presented herein represents a product in prototyping or pre-production. The noted characteristics are based on initial
product characterization. Integrated Circuit Systems, Incorporated (ICS) reserves the right to change any circuitry or specifications without notice.

IDT™ / ICS™ LVDS/LVCMOS FREQUENCY SYNTHESIZER 1 ICS8440258-46 REV B AUGUST 24, 2006

ICS8440258-46
FEMTOCLOCK™ CRYSTAL/LVCMOS-TO-LVDS/ LVCMOS FREQUENCY SYNTHESIZER PRELIMINARY

TABLE 1. PIN DESCRIPTIONS

rebmuNemaNepyTnoitpircseD

2,10Qn,0QtuptuO.slevelecafretniSDVL.stuptuokcolclaitnereffiD

,61,21,3

12,71

5,41Qn,1QtuptuO.slevelecafretniSDVL.stuptuokcolclaitnereffiD

72,11,6V

8,72Qn,2QtuptuO.slevelecafretniSDVL.stuptuokcolclaitnereffiD

01,93Qn,3QtuptuO.slevelecafretniSDVL.stuptuokcolclaitnereffiD

,51,31

02,81

41V

91V

42,32,22cndesunU.tcennocoN

52V

62LES_LLPntupnInwodlluP

82RMtupnInwodlluP

92KLC_FERtupnInwodlluP.tupnikcolcecnereferLTTVL/SOMCVLdedne-elgniS

03LES_LATXntupnInwodlluP

,13

23

:ETON

DNGrewoP.dnuorgylppusrewoP

DD

,5Q,4Q

7Q,6Q

1ODD

2ODD

ADD

,TUO_LATX

NI_LATX

rewoP.nipylppuseroC

tuptuO .slevelecafretniLTTVL/SOMCVL.stuptuokcolcdedne-elgniS

rewoP .stuptuoSOMCVL5Qdna4QrofnipylppustuptuorewoP

rewoP .stuptuoSOMCVL7Qdna6QrofnipylppustuptuorewoP

rewoP.nipylppusgolanA

tupnI

nwodlluP

.tuptuoOCVehtmorfnevirdsituptuoeht,WOLnehW.ssapyBLLP

=ycneuqerftuptuoehtdnadessapybsiLLPeht,HGIHnehW

.redividtuptuoN/ycneuqerfkcolcecnerefer

.slevelecafretniLTTVL/SOMCVL

erasredividlanretnieht,HGIHcigolnehW.teseRretsaMHGIHevitcA

lanretnieht,WOLcigolnehW.wologotstuptuoehtgnisuacteser

.slevelecafretniLTTVL/SOMCVL.delbaneerastuptuoehtdnasredivid

ecnereferLLPehtsastupniKLC_FERrolatsyrcehtneewtebstceleS

LATXstceles,WOLnehW.KLC_FERstceles,HGIHnehW.ecruos

.slevelecafretniLTTVL/SOMCVL.stupni

.tuptuoehtsiTUO_LATX.ecafretnirotallicsolatsyrC

.tupniehtsiNI_LATX

.seulavlacipytrof,scitsiretcarahCniP,2elbaTeeS.srotsisertupnilanretniotsrefer

TABLE 2. PIN CHARACTERISTICS

lobmySretemaraPsnoitidnoCtseTmuminiMlacipyTmumixaMstinU

C

NI

C

DP

R

R

IDT™ / ICS™ LVDS/LVCMOS FREQUENCY SYNTHESIZER 2 ICS8440258-46 REV B AUGUST 24, 2006

NWODLLUP

TUO

ecnaticapaCtupnI 4Fp

ecnaticapaCnoitapissiDrewoP 8Fp

rotsiseRnwodlluPtupnI 15kΩ

ecnadepmItuptuO 22

Ω

ICS8440258-46
FEMTOCLOCK™ CRYSTAL/LVCMOS-TO-LVDS/ LVCMOS FREQUENCY SYNTHESIZER PRELIMINARY

ABSOLUTE MAXIMUM RATINGS

Supply Voltage, V

Inputs, V

Outputs, I

Outputs, I

I

(LVCMOS) -0.5V to V

O

(LVDS)

O

DD

4.6V

-0.5V to V

+ 0.5V

DD

+ 0.5V

DD

Continuous Current 10mA
Surge Current 15mA

Operating Temperature Range, TA -40°C to +85°C

NOTE: Stresses beyond those listed under Absolute Maximum

Ratings may cause permanent damage to the device. These

ratings are stress specifications only. Functional operation of

product at these conditions or any conditions beyond those listed

DC Characteristics

in the

or

AC Characteristics

is not implied.

Exposure to absolute maximum rating conditions for extended

periods may affect product reliability.

Storage Temperature, T

STG

Package Thermal Impedance, θ

TABLE 3A. POWER SUPPLY DC CHARACTERISTICS, V

-65°C to 150°C

34.8°C/W (0 lfpm)

JA

DD

lobmySretemaraPsnoitidnoCtseTmuminiMlacipyTmumixaMstinU

V

DD

V

ADD

V

ODD

I

I

I

I

,DD

,1ODD

2ODD

ADD

egatloVylppuSeroC573.25.2526.2V

egatloVylppuSgolanAV

egatloVylppuStuptuO573.25.2526.2V

tnerruCylppuSrewoP 071Am

tnerruCylppuSgolanA 31Am

TABLE 3B. LVCMOS/LVTTL DC CHARACTERISTICS, V

lobmySretemaraPsnoitidnoCtseTmuminiMlacipyTmumixaMstinU

V

HI

V

LI

I

HI

I

LI

tupnI

tupnI

tuptuO

V

HO

1ETON

tuptuO

V

LO

1ETON

egatloVhgiHtupnI 7.1V

egatloVwoLtupnI 3.0-7.0V

,KLC_FER,RM

tnerruChgiH

LES_LATXn,LES_LLPn

,KLC_FER,RM

tnerruCwoL

;egatloVhgiH

;egatloVwoL

7Q:4Q

7Q:4Q

05htiwdetanimretstuptuO:1ETON Ω Vot

.margaidtiucriCtseTdaoLtuptuO

LES_LATXn,LES_LLPn

XODD

= V

V

V

DD

V

DDA

= V

VDDV=

DD

= V

DDA

V

,1ODD

V

,1ODD

= V

DDO1

= V

DDO1

NI

=V526.2%5±

1ODD

=V526.2%5±

1ODD

= 2.5V ± 5%,TA = 0°C TO 70°C

DDO2

31.0–5.2VDDV

DD

= V

= 2.5V ± 5%,TA = 0°C TO 70°C

DDO2

DD

V526.2=051Aµ

V,V526.2=

V0=5-Aµ

NI

8.1V

,noitamrofnItnemerusaeMretemaraPeeS.2/

3.0+V

5.0V

IDT™ / ICS™ LVDS/LVCMOS FREQUENCY SYNTHESIZER 3 ICS8440258-46 REV B AUGUST 24, 2006

ICS8440258-46
FEMTOCLOCK™ CRYSTAL/LVCMOS-TO-LVDS/ LVCMOS FREQUENCY SYNTHESIZER PRELIMINARY

TABLE 3C. LVDS DC CHARACTERISTICS, V

lobmySretemaraPsnoitidnoCtseTmuminiMlacipyTmumixaMstinU

V

∆ V

V

∆ V

DO

V

DO

SO

SO

DO

egatloVtesffO 52.1V

V

SO

egatloVtuptuOlaitnereffiD 093Vm

egnahCedutingaM 05Vm

egnahCedutingaM 05Vm

TABLE 4. CRYSTAL CHARACTERISTICS

retemaraPsnoitidnoCtseTmuminiMlacipyTmumixaMstinU

noitallicsOfoedoM latnemadnuF

ycneuqerF 52zHM

)RSE(ecnatsiseRseireStnelaviuqE 05

ecnaticapaCtnuhS 7Fp

leveLevirD 1Wm

TABLE 5. AC CHARACTERISTICS, V

lobmySretemaraPsnoitidnoCtseTmuminiMlacipyTmumixaMstinU

f

TUO

t

)o(ks

t

)Ø(tij

t

Rt/F

cdoelcyCytuDtuptuO

tuptuO

VtaderusaeM

XODD

ycneuqerFtuptuO

;wekStuptuO

2,1ETON

rettiJesahPSMR

emiTllaF/esiR

.2/

= V

DD

DDA

5Q,4Q521zHM

7Q,6Q52zHM

7Q:4Q05sp

3ETON;)modnaR(

5Q,4Q)zHM02-zHM578.1(,zHM52173.0sp

7Q:4Q%08ot%024.1sn

7Q:4Q6445%

= V

DD

DDA

= V

DDO1

= V

= 2.5V ± 5%,TA = 0°C TO 70°C

DDO2

Ω

.latsyrctnanoserlellarapFp81nagnisudeziretcarahC:ETON

= V

= V

DDO1

= 2.5V ± 5%,TA = 0°C TO 70°C

DDO2

3:0Qn/3:0Q521zHM

3:0Qn/3:0Q05sp

3:0Qn/3:0Q)zHM02-zHM578.1(,zHM52143.0sp

3:0Qn/3:0Q%08ot%02084sp

3:0Qn/3:0Q05%

.snoitidnocdaollauqehtiwdnasegatlovylppusemasehttastuptuoneewtebwekssadenifeD:1ETON

.56dradnatSCEDEJhtiwecnadroccanidenifedsiretemarapsihT:2ETON

.tolPesioNesahPehtotreferesaelP:3ETON

IDT™ / ICS™ LVDS/LVCMOS FREQUENCY SYNTHESIZER 4 ICS8440258-46 REV B AUGUST 24, 2006

ICS8440258-46
FEMTOCLOCK™ CRYSTAL/LVCMOS-TO-LVDS/ LVCMOS FREQUENCY SYNTHESIZER PRELIMINARY

TYPICAL PHASE NOISE AT 125MHZ (LVCMOS)

0

➤

Ethernet Filter

125MHz

dBc

NOISE POWER

Hz

-10

-20

-30

-40

-50

-60

-70

-80

-90

-100

-110

-120

-130

-140

-150

-160

-170

-180

-190

-200
10 100 1k 10k 100k 1M 10M 100M

Raw Phase Noise Data

➤

1.875MHz to 20MHz = 0.37ps (typical)

➤

Phase Noise Result by adding
Ethernet Filter to raw data

RMS Phase Jitter (Random)

OFFSET FREQUENCY (HZ)

dBc

NOISE POWER

Hz

TYPICAL PHASE NOISE AT 125MHZ (LVDS)

0

-10

-20

-30

-40

-50

-60

-70

-80

-90

-100

-110

-120

-130

-140

-150

-160

-170

-180

-190

-200
10 100 1k 10k 100k 1M 10M 100M

Raw Phase Noise Data

➤

1.875MHz to 20MHz = 0.34ps (typical)

➤

Phase Noise Result by adding
Ethernet Filter to raw data

RMS Phase Jitter (Random)

OFFSET FREQUENCY (HZ)

➤

Ethernet Filter

125MHz

IDT™ / ICS™ LVDS/LVCMOS FREQUENCY SYNTHESIZER 5 ICS8440258-46 REV B AUGUST 24, 2006

ICS8440258-46
FEMTOCLOCK™ CRYSTAL/LVCMOS-TO-LVDS/ LVCMOS FREQUENCY SYNTHESIZER PRELIMINARY

PARAMETER MEASUREMENT INFORMATION

1.25V±5%

1.25V±5%

,

V

DD

V

DDO1,

V

DDO2

LVCMOS

GND

V

DDA

Qx

2.5V±5%

POWER SUPPLY

+–

Float GND

V
V
V

DD

DDO1,

DDO2

SCOPE

,

V

DDA

LVDS

Qx

nQx

-1.25V±5%

2.5V LVDS OUTPUT LOAD AC TEST CIRCUIT 2.5V LVCMOS OUTPUT LOAD AC TEST CIRCUIT

nQx

Qx

nQy

Qy

t

sk(o)

Qx

Qy

V

DDO

2

V

DDO

2

t

sk(o)

SCOPE

LVDS OUTPUT SKEW

80%

Clock
Outputs

20%

t

R

LVDS OUTPUT RISE/FALL TIME

80%

t

F

20%

V

OD

LVCMOS OUTPUT SKEW

80%

20%

Clock
Outputs

t

R

LVCMOS OUTPUT RISE/FALL TIME

80%

t

F

20%

IDT™ / ICS™ LVDS/LVCMOS FREQUENCY SYNTHESIZER 6 ICS8440258-46 REV B AUGUST 24, 2006