IDT5T2010
INDUSTRIALTEMPERATURERANGE
2.5VZERODELAYPLLCLOCKDRIVER TERACLOCK
PINDESCRIPTION,CONTINUED
Symbol
REF_SEL
nsOE
I/O
Type
Description
(1)
I
I
LVTTL
Reference clock select. When LOW, selects REF0 and REF0/VREF0. When HIGH, selects REF1 and REF1/VREF1.
(1)
LVTTL
Synchronousoutputenable. WhennsOEisHIGH,nQ[1:0]aresynchronouslystopped. OMODEselectswhethertheoutputsaregated
LOW/HIGH or tri-stated. When OMODE is HIGH, PE determines the level at which the outputs stop. When PE is LOW/HIGH, the
nQ[1:0] is stopped in a HIGH/LOW state. When OMODE is LOW, the outputs are tri-stated. Set nsOE LOW for normal operation.
QFB
QFB
nQ[1:0]
RxS
O
O
O
I
Adjustable(2) Feedbackclockoutput
Adjustable(2) Complementaryfeedbackclockoutput
Adjustable(2) Fivebanks oftwooutputs
(3)
3-Level
Selects single-ended2.5VLVTTL(HIGH), 1.8VLVTTL(MID)REFclockinputordifferential(LOW)REFclockinput
(3)
TxS
I
3-Level
Setsthedrivestrengthoftheoutputdriversandfeedbackinputstobe2.5VLVTTL(HIGH),1.8VLVTTL(MID)orHSTL/eHSTL(LOW)
compatible. UsedinconjuctionwithVDDQ tosettheinterfacelevels.
(1)
PE
I
LVTTL
Selectablepositiveornegativeedgecontrol. WhenLOW/HIGHtheoutputsaresynchronizedwiththenegative/positiveedgeofthereference
clock(hasinternalpull-up).
(1)
nF[2:1]
FBF[2:1]
FS
I
I
I
I
I
I
LVTTL
Functionselectinputs fordivide-by-2,divide-by-4,zerodelay,orinvertoneachbank(SeeControlSummarytable)
Functionselectinputsfordivide-by-2,divide-by-4,zerodelay,orinvertonthefeedbackbank(SeeControlSummarytable)
Selectsappropriateoscillatorcircuitbasedonanticipatedfrequencyrange. (SeeVCOFrequencyRangeSelect.)
3-levelinputsforfeedbackinputdividerselection(SeeDivideSelectiontable)
(1)
LVTTL
(1)
LVTTL
(3)
DS[1:0]
PLL_EN
PD
3-Level
(1)
LVTTL
PLLenable/disablecontrol. SetLOWfornormaloperation. WhenPLL_ENisHIGH,thePLLisdisabledandREF[1:0]goestoalloutputs.
(1)
LVTTL
Powerdowncontrol. WhenPDisLOW,theinputsaredisabledandinternalswitchingisstopped. OMODEselectswhethertheoutputs
are gated LOW/HIGH or tri-stated. When OMODE is HIGH, PE determines the level at which the outputs stop. When PE is LOW/
HIGH, the nQ[1:0] and QFB are stopped in a HIGH/LOW state, while the QFB is stopped in a LOW/HIGH state. When OMODE is
LOW,theoutputs aretri-stated. SetPDHIGHfornormaloperation.
LOCK
O
I
LVTTL
PLLlockindicationsignal. HIGHindicateslock. LOWindicatesthatthePLLisnotlockedandoutputsmaynotbesynchronizedtothe
inputs. Theoutputwillbe2.5VLVTTL. (FormoreinformationonapplicationspecificuseoftheLOCKpin,pleaseseeAN237.)
(1)
OMODE
LVTTL
Outputdisablecontrol. Determinestheoutputs'disablestate. UsedinconjunctionwithnsOEandPD. (SeeOutputEnable/Disableand
Powerdowntables.)
VDDQ
VDD
PWR
PWR
PWR
Powersupplyforoutputbuffers. Whenusing2.5VLVTTL,VDDQshouldbeconnectedtoVDD.
Powersupplyforphaselockedloop,lockoutput,inputs,andotherinternalcircuitry
Ground
GND
NOTES:
1. Pins listed as LVTTL inputs will accept 2.5V signals under all conditions. If the output is operating at 1.8V or 1.5V, the LVTTL inputs will accept 1.8V LVTTL signals as well.
2. Outputs are user selectable to drive 2.5V, 1.8V LVTTL, eHSTL, or HSTL interface levels when used with the appropriate VDDQ voltage.
3. 3-level inputs are static inputs and must be tied to VDD or GND or left floating. These inputs are not hot-insertable or over voltage tolerant.
OUTPUTENABLE/DISABLE
nsOE
L
OMODE
Output
NormalOperation
Tri-State
VCOFREQUENCYRANGESELECT
X
L
FS(1)
LOW
HIGH
Min.
50
Max.
125
Unit
MHz
MHz
H
H
H
Gated(1)
100
250
NOTE:
NOTE:
1. PE determines the level at which the outputs stop. When PE is LOW/HIGH, the
nQ[1:0] is stopped in a HIGH/LOW state.
1. The level to be set on FS is determined by the nominal operating frequency of the
VCO. The VCO frequency (FNOM) always appears at nQ[1:0] outputs when they are
operated in their undivided modes. The frequency appearing at the REF[1:0] and
REF[1:0] /VREF[1:0] and FB and FB/VREF2 inputs will be FNOM when the QFB and QFB
are undivided and DS[1:0] = MM. The frequency of REF[1:0] and REF[1:0] /VREF[1:0]
and FB and FB/VREF2 inputs will be FNOM/2 or FNOM/4 when the part is configured for
frequency multiplication by using a divided QFB and QFB and setting DS[1:0] = MM.
Using the DS[1:0] inputs allows a different method for frequency multiplication (see
Divide Selection table).
POWERDOWN
PD
H
L
OMODE
Output
NormalOperation
Tri-State
X
L
L
H
Gated(1)
NOTE:
1. PE determines the level at which the outputs stop. When PE is LOW/HIGH, the
nQ[1:0] and QFB are stopped in a HIGH/LOW state, while the QFB is stopped in a
LOW/HIGH state.
5