Obtaining Accurate Device-Only S-Parameter Data to 15 … · Obtaining Accurate Device-Only S-Parameter Data to 15 ... fully characterize the lead inductance of the ... to higher

Copyright A Tyco International Ltd. Company 2004

Circuits & Design

Obtaining Accurate DeviceObtaining Accurate Device--OnlyOnlySS--Parameter Data to 15Parameter Data to 15--20 GHz20 GHz

Using InUsing In--FixtureFixtureMeasurement TechniquesMeasurement Techniques

Chad W. MorganChad W. MorganFebruary 3, 2004February 3, 2004

Technical Session 7-TP1


Circuits & Design2

Presentation Outline

In-FixtureTechnique

Comparison

TRL/LRMCalibration

Success Stories

FrequencyDomain

Considerations

In-FixtureMeasurementTechniques

TRL/LRMCalibration

Implementation

Side FlowchartAlways HighlightsCurrent LocationIn Presentation


Circuits & Design3

Frequency Domain Considerations


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

FrequencyDomain

Considerations

FrequencyDomain

Considerations

• Why Measure in the Frequency Domain?• Why Data to 15-20 GHz?

• Why ‘In-Fixture’ Measurements?


Circuits & Design4

•• DUTDUT--ONLY measurement capabilityONLY measurement capability–– All test fixture effects removedAll test fixture effects removed

Why Measure in the Frequency Domain?


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

FrequencyDomain

Considerations

•• DISTRIBUTED data for highDISTRIBUTED data for high--speed modelsspeed models–– Lumped models inadequate above several GHzLumped models inadequate above several GHz

Insertion Loss

-10.0

-9.0

-8.0

-7.0

-6.0

-5.0

-4.0

-3.0

-2.0

-1.0

0.0

1.0E+08 1.0E+09 1.0E+10Frequency (Hz)

Am

plitu

de R

atio

(dB)

•• FINISHED measurement model for the DUTFINISHED measurement model for the DUT–– Can calculate any electrical valueCan calculate any electrical value–– Can reconstruct time domain signals via IFFTsCan reconstruct time domain signals via IFFTs

•• FULL characterization of Device Under Test (FULL characterization of Device Under Test (DUTDUT))–– Direct display of performance vs. speedDirect display of performance vs. speed–– Easy detection of narrowband resonancesEasy detection of narrowband resonances


Circuits & Design5

Why Data to 15-20 GHz?

•• Experience shows that 20 GHz data allows good Experience shows that 20 GHz data allows good transforms for 10 Gbps waves & 25 ps edge ratestransforms for 10 Gbps waves & 25 ps edge rates


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

FrequencyDomain

Considerations

GHzpsT

Fr

BW 2025

5.05.0 ===Signal Integrity ‘Rule of Thumb’: The majority of a signal’s energy lies below FBW

•• Practical transform approachPractical transform approach

Sampling every 5ps (20 samples/bit) requires data to 100 GHz!! - Difficult to measure (λ in air = 3 mm)

GHzpsT

Fs

1005*21

*21

max ===

•• Rigorous transform approach:Rigorous transform approach:

•• HighHigh--speed serial links are speed serial links are pushing 10 Gbpspushing 10 Gbps


Circuits & Design6

Why ‘In-Fixture’ Measurements?


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

FrequencyDomain

Considerations

•• Uniform standards measurementsUniform standards measurements–– Standards available for many RF interfacesStandards available for many RF interfaces–– Implementation well documentedImplementation well documented

–– NO REMOVAL OF TEST FIXTURE EFFECTSNO REMOVAL OF TEST FIXTURE EFFECTSREF1 REF2

DUT

–– Only removes VNA/cable/adapter effectsOnly removes VNA/cable/adapter effects–– NO REMOVAL OF TEST FIXTURE EFFECTSNO REMOVAL OF TEST FIXTURE EFFECTS


Circuits & Design7

Why ‘In-Fixture’ Measurements?


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

FrequencyDomain

Considerations

REF1 REF2DUT

–– ALLOWS DUTALLOWS DUT--ONLY MEASUREMENTONLY MEASUREMENT

•• ‘‘InIn--Fixture’ measurementsFixture’ measurements–– Standards must be customStandards must be custom--designeddesigned–– Documentation more challenging to findDocumentation more challenging to find


Circuits & Design8

In-Fixture Measurement Techniques


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

Normalization

Time Gating

[T] Deembed

FrequencyDomain

Considerations

SOLT Cal


• SOLT Calibration• TRL/LRM Calibration

• Normalization• Enhanced Time Domain Gating

• [ T ] Matrix Deembedding


Circuits & Design9

Presentation Terminology


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

Normalization

Time Gating

[T] Deembed

FrequencyDomain

Considerations

SOLT Cal

•• DeembeddingDeembedding–– Removal of the unwanted measurement portion, GIVEN Removal of the unwanted measurement portion, GIVEN

a known response for the fixture errora known response for the fixture error–– [ T ] matrices & e[ T ] matrices & e--γγll

•• CalibrationCalibration–– Characterization AND removal of the unwanted Characterization AND removal of the unwanted

measurement portion using known standardsmeasurement portion using known standards–– SOLT & TRLSOLT & TRL

•• Note: Many other methods exist Note: Many other methods exist -- only those only those above are being covered in this presentationabove are being covered in this presentation

•• Error CorrectionError Correction–– Removal of the unwanted measurement portion, using Removal of the unwanted measurement portion, using

postpost--calibration mathematical techniquescalibration mathematical techniques–– Normalization, gating, & enhanced gating Normalization, gating, & enhanced gating


Circuits & Design10

SOLT (SHORT-OPEN-LOAD-THRU) Calibration


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

Normalization

Time Gating

[T] Deembed

FrequencyDomain

Considerations

SOLT Cal

•• Classic technique that most people useClassic technique that most people use•• Makes use of full 12Makes use of full 12--term error modelterm error model

EDF = Forward Directivity

ESF = Forward Source Match

ERF = Forward Reflection Tracking

ETF = Forward Transmission Tracking

ELF = Forward Load Match

EXF= Forward Isolation

EDR = Reverse Directivity

ESR = Reverse Source Match

ERR = Reverse Reflection Tracking

ETR = Reverse Transmission Tracking

ELR = Reverse Load Match

EXR = Reverse Isolation


Circuits & Design11



TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

Normalization

Time Gating

[T] Deembed

FrequencyDomain

Considerations

SOLT Cal

•• Characterization of directivity, source match, Characterization of directivity, source match, and reflection tracking (both directions)and reflection tracking (both directions)

IMPERFECT LOAD, OPEN, & SHORT standards MUST BE CHARACTERIZED!-LOAD must be perfect (or known)-OPEN fringe capacitance must be known-SHORT lead inductance must be known

3453

2362

271

150 )10()10()10()10()( fCfCfCCFCeff

−−−− •+•+•+•=342

3233

224

112

0 )10()10()10()10()( fLfLfLLHLeff−−−− •+•+•+•=


Circuits & Design12



TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

Normalization

Time Gating

[T] Deembed

FrequencyDomain

Considerations

SOLT Cal

Isolation typically omitted since it is below the noise floor of the VNA (unless averaging used)

Must know Zo and Tpd of THRU

LOAD match is the return loss of the THRU, measured with 1-port that is already calibrated (from previous slide)

•• Characterization of transmission tracking, Characterization of transmission tracking, load match, and isolationload match, and isolation


Circuits & Design13



TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

Normalization

Time Gating

[T] Deembed

FrequencyDomain

Considerations

SOLT Cal

•• Once all 12 error terms are known, test fixture Once all 12 error terms are known, test fixture error can be removed from the measurement:error can be removed from the measurement:


Circuits & Design14



TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

Normalization

Time Gating

[T] Deembed

FrequencyDomain

Considerations

SOLT Cal

•• Well known & easily completed with uniform Well known & easily completed with uniform standardsstandards

•• Difficult to implement w/ ‘inDifficult to implement w/ ‘in--fixture’ standardsfixture’ standards–– Must perfect or fully characterize the LOAD at high Must perfect or fully characterize the LOAD at high

frequency (extremely difficult)frequency (extremely difficult)–– Must eliminate or fully characterize the fringe Must eliminate or fully characterize the fringe

capacitance of the OPEN (difficult but achievable)capacitance of the OPEN (difficult but achievable)–– Must eliminate or fully characterize the lead Must eliminate or fully characterize the lead

inductance of the SHORT (difficult but achievable)inductance of the SHORT (difficult but achievable)–– Must characterize impedance and delay of the Must characterize impedance and delay of the

THRU (relatively easy)THRU (relatively easy)

•• Characterization of SOLT standards relies on Characterization of SOLT standards relies on modeling or other test methods (modeling or other test methods (selfself--defeatingdefeating))


Circuits & Design15

TRL (THRU-REFLECT-LINE) Calibration


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

Normalization

Time Gating

[T] Deembed

FrequencyDomain

Considerations

SOLT Cal

•• Characterization math of fixture error and Characterization math of fixture error and deembedding of that error is very different deembedding of that error is very different than SOLTthan SOLT

LaunchError

ReceiveError

THRU

REF1 REF2

LaunchError

ReceiveError

LINE(s)

REF1 REF2

REF1 REF2

LaunchError

ReceiveError

REFLECT(SHORT or OPEN)

•• Calibration technique uses standards belowCalibration technique uses standards below


Circuits & Design16



TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

Normalization

Time Gating

[T] Deembed

FrequencyDomain

Considerations

SOLT Cal

•• More recent calibration techniqueMore recent calibration technique

N. R. Franzen & R. A. Speciale, “A New Procedure for System Calibration & Error Removal in Automated S-parameter Measurements”, Proc. 5th European Microwave Conf, Sep, 1975.

–– Sep, 1975: TSD Calibration Technique IntroducedSep, 1975: TSD Calibration Technique Introduced

Glenn Engen and Cletus Hoer, “Thru-Reflect-Line: An Improved Technique for Calibrating the Dual Six-Port Automatic Network Analyzer”, IEEE-MTT Vol. MTT-27, No. 12, Dec, 1979.

–– Dec, 1979: Improvement to TSD; ‘TRL’ first mentionedDec, 1979: Improvement to TSD; ‘TRL’ first mentioned

Renato Pantoja, Michael Howes, John Richardson, and Roger Pollard, “Improved Calibration and Measurement of the Scattering Parameters of Microwave Integrated Circuits”, IEEE-MTT Vol. 37, No. 11, Nov, 1989.

–– Nov, 1989: TRL improved…pretty much as it is used todayNov, 1989: TRL improved…pretty much as it is used today

Michael Rubin, “De-embedding MM-wave MICs with TRL”, Microwave Journal, Jun, 1990.

–– Jun, 1990: Useful, easyJun, 1990: Useful, easy--toto--follow outlining of TRL mathfollow outlining of TRL math

•• Math too long to include here Math too long to include here –– examine examine Rubin article for more detailRubin article for more detail


Circuits & Design17



TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

Normalization

Time Gating

[T] Deembed

FrequencyDomain

Considerations

SOLT Cal

•• TRL advantagesTRL advantages–– THRU: Typically requires no characterizationTHRU: Typically requires no characterization–– REFLECT: No need for characterizationREFLECT: No need for characterization

•• Need only approximate phase (OPEN or SHORT)Need only approximate phase (OPEN or SHORT)•• Needs to be the same for both portsNeeds to be the same for both ports

–– LINEs: Only require ZLINEs: Only require Zoo & T& Tpdpd characterizationcharacterization–– LOAD: None involved!LOAD: None involved!

•• TRL restrictionsTRL restrictions–– THRU: Launch/receive must be same transmission THRU: Launch/receive must be same transmission

line type (directly connectable)line type (directly connectable)–– LINEs: Need several LINEs across frequency LINEs: Need several LINEs across frequency

•• Each LINE has numerical difficulty with some Each LINE has numerical difficulty with some frequenciesfrequencies

•• Low frequency LINEs become too long for practical Low frequency LINEs become too long for practical implementationimplementation


Circuits & Design18

•• LRM calibration for low frequencyLRM calibration for low frequency–– TRL algorithm with LOAD, instead of LINEsTRL algorithm with LOAD, instead of LINEs–– Convenient routine for low frequencyConvenient routine for low frequency

•• TRL LINEs are too long for practical implementationTRL LINEs are too long for practical implementation•• Accurate LOAD achievable at low frequencyAccurate LOAD achievable at low frequency

–– Combination of TRL/LRM calibration at Combination of TRL/LRM calibration at high/low frequency makes for an accurate, high/low frequency makes for an accurate, realizable inrealizable in--fixture calibration methodfixture calibration method

LRM (LOAD-REFLECT-MATCH) Calibration


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

Normalization

Time Gating

[T] Deembed

FrequencyDomain

Considerations

SOLT Cal

LaunchError

REF1/2

LOADLaunchError

THRU

REF1 REF2

ReceiveError

LaunchError

REF1/2

REFLECT

LaunchError

LINE(s)

REF1 REF2

ReceiveError


Circuits & Design19



TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

Normalization

Time Gating

[T] Deembed

FrequencyDomain

Considerations

SOLT Cal

•• Uniform TRL standards are availableUniform TRL standards are available–– Typically rated to higher frequency than SOLTTypically rated to higher frequency than SOLT–– Example: Agilent 85052C 3.5mm kitExample: Agilent 85052C 3.5mm kit

•• This presentation focuses on inThis presentation focuses on in--fixture fixture TRL/LRM (building your own standards)TRL/LRM (building your own standards)

•• Variations of TRL/LRM algorithmVariations of TRL/LRM algorithm–– TRL*/LRM* TRL*/LRM* -- Not as efficient in removing Not as efficient in removing

unwanted test fixture resonancesunwanted test fixture resonances–– LRM with LOAD compensation LRM with LOAD compensation –– Extends LRM Extends LRM

technique to higher frequency by characterizing technique to higher frequency by characterizing LOAD inductanceLOAD inductance


Circuits & Design20

Normalization

–– In linear scale, divide DUT by THRUIn linear scale, divide DUT by THRU


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

Normalization

Time Gating

[T] Deembed

FrequencyDomain

Considerations

SOLT Cal

−

•• Also referred to as response calibrationAlso referred to as response calibration•• Normalization procedure:Normalization procedure:

REF1 REF2

THRU

–– For two port measurement, measure test fixture For two port measurement, measure test fixture THRU (DUT removed)THRU (DUT removed)

–– In dB scale, subtract THRU from DUTIn dB scale, subtract THRU from DUT

DUTREF1 REF2

–– Calibrate to uniform standardsCalibrate to uniform standards–– Measure the DUT, including test fixturingMeasure the DUT, including test fixturing

÷


Circuits & Design21

Normalization•• AdvantagesAdvantages

–– Relatively easy to completeRelatively easy to complete–– Corrects for loss and delayCorrects for loss and delay

•• DisadvantagesDisadvantages–– Does NOT correct for fixture reflectionsDoes NOT correct for fixture reflections–– Inaccurate if fixture or DUT have Inaccurate if fixture or DUT have

significant reflectionssignificant reflections•• Often used at low frequencyOften used at low frequency•• Often used for structures like cablesOften used for structures like cables

•• Normalization WILL NOT correct Normalization WILL NOT correct properly for resonances in frequency!properly for resonances in frequency!


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

Normalization

Time Gating

[T] Deembed

FrequencyDomain

Considerations

SOLT Cal


Circuits & Design22

Time Domain Gating•• Time domain gating procedure:Time domain gating procedure:

–– Calibrate to uniform standardsCalibrate to uniform standards–– Measure the DUT, including test fixturingMeasure the DUT, including test fixturing–– Transform response to time domain and set gatesTransform response to time domain and set gates–– Transform time response between gates back to Transform time response between gates back to

the frequency domainthe frequency domain–– Test fixture resonances are now removedTest fixture resonances are now removed


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

Time Gating

Normalization

[T] Deembed

FrequencyDomain

Considerations

SOLT Cal

DUTREF1 REF2


Circuits & Design23

Enhanced Time Domain Gating•• ‘‘Enhancement’ to time domain gatingEnhancement’ to time domain gating

–– Complete the same procedure from the previous Complete the same procedure from the previous page for the THRU calibration structurepage for the THRU calibration structure

–– In linear scale, divide gated DUT by gated THRUIn linear scale, divide gated DUT by gated THRU–– In dB scale, subtract gated THRU from gated DUTIn dB scale, subtract gated THRU from gated DUT–– Test fixture resonances, loss, and delay are now Test fixture resonances, loss, and delay are now

removed from the measurementremoved from the measurement


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

Time Gating

Normalization

[T] Deembed

FrequencyDomain

Considerations

SOLT Cal

DUTREF1 REF2 REF1 REF2

THRU

−÷


Circuits & Design24

Enhanced Time Domain Gating•• AdvantagesAdvantages

–– Only calibration structure is the THRUOnly calibration structure is the THRU–– Data, in general, can be very accurateData, in general, can be very accurate

•• DisadvantagesDisadvantages–– Complex implementationComplex implementation

•• Must complete math on EACH sMust complete math on EACH s--parameterparameter•• Gate placement requires user judgmentGate placement requires user judgment•• Test fixturing must allow inclusion/exclusion timesTest fixturing must allow inclusion/exclusion times•• Care must be taken with transformsCare must be taken with transforms

–– Data can be inaccurate in specific casesData can be inaccurate in specific cases•• Band edges inaccurate due to windowingBand edges inaccurate due to windowing•• Reflection phase is not accurateReflection phase is not accurate

•• NotesNotes–– S21 CAN be obtained without gating a TDT S21 CAN be obtained without gating a TDT

waveformwaveform–– Procedure best for analysis, not for creating standProcedure best for analysis, not for creating stand--

alone DUT modelsalone DUT models


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

Time Gating

Normalization

[T] Deembed

FrequencyDomain

Considerations

SOLT Cal


Circuits & Design25

[ T ] Matrix Deembedding•• GIVEN sGIVEN s--parameters for the launch [Sparameters for the launch [SLL], the ], the

receive [Sreceive [SRR], and the DUT], and the DUT--withwith--fixture [Sfixture [SLDRLDR], one ], one can derive the scan derive the s--parameters for the DUT [Sparameters for the DUT [SDD]:]:–– Convert [SConvert [SLL], [S], [SRR], and S[], and S[LDRLDR] to [T] parameters (1)] to [T] parameters (1)–– Determine the [T] matrix for the DUT (2)Determine the [T] matrix for the DUT (2)–– Convert the [TConvert the [TDD] matrix back to s] matrix back to s--parameters [Sparameters [SDD] (3)] (3)


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

Time Gating

Normalization

[T] Deembed

FrequencyDomain

Considerations

SOLT Cal

DUTREF1 REF2

[ ]LS [ ]DS [ ]RS

[ ]LDRS

−

•−•−

=

2121

22

21

11

21

21122211

1SS

SSS

SSSSS

T(1)

[ ] [ ] [ ][ ] 11 −−= RLDRLD TTTT(2)

−

•−•

=

22

21

22

22

21122211

22

12

1TT

T

TTTTT

TT

S(3)


Circuits & Design26

•• Advantages:Advantages:–– Relatively simple mathRelatively simple math–– Removes loss, delay, and resonancesRemoves loss, delay, and resonances

•• Disadvantages:Disadvantages:–– Must know [SMust know [SLL] and [S] and [SRR]]

•• Must model or somehow measure preciselyMust model or somehow measure precisely•• (or must be omniscient)(or must be omniscient)

•• Note:Note:–– Matrix conversions can be derived for more than Matrix conversions can be derived for more than

two portstwo ports

[ T ] Matrix Deembedding


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

Time Gating

Normalization

[T] Deembed

FrequencyDomain

Considerations

SOLT Cal


Circuits & Design27

In-Fixture Technique Comparison


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

Normalization

Time Gating

[T] Deembed

FrequencyDomain

Considerations

SOLT Cal

In-FixtureTechnique

Comparison

• SOLT Calibration• TRL/LRM Calibration

• Normalization• Enhanced Time Domain Gating

• [ T ] Matrix Deembedding


Circuits & Design28

Creating Controlled Comparison


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

Normalization

Time Gating

[T] Deembed

FrequencyDomain

Considerations

SOLT Cal

•• Test boards built w/ inTest boards built w/ in--fixture standardsfixture standards–– SHORT, OPEN, LOAD, THRU, LINESSHORT, OPEN, LOAD, THRU, LINES–– Multiple transmission line types and lengthsMultiple transmission line types and lengths–– Multiple test point variations (SMAs shown)Multiple test point variations (SMAs shown)


Circuits & Design29

The ‘knownDUT’ Concept


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

Normalization

Time Gating

[T] Deembed

FrequencyDomain

Considerations

SOLT Cal

•• Note: For accurate performance prediction:Note: For accurate performance prediction:–– Must measure real geometry (Must measure real geometry (µµsections)sections)–– Must know Must know εεrr and tanand tanδδ vs. frequencyvs. frequency

•• Structure chosen to benchmark methodsStructure chosen to benchmark methods–– Sample performance must be predictableSample performance must be predictable

•• Parametric equationsParametric equations•• Field solversField solvers

–– Sample needs to be lossy and reflectiveSample needs to be lossy and reflective

REF1 REF2


Circuits & Design30



TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

Normalization

Time Gating

[T] Deembed

FrequencyDomain

Considerations

SOLT Cal

•• Predicted ‘knownDUT’ sPredicted ‘knownDUT’ s--parametersparameters


Circuits & Design31



TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

Normalization

Time Gating

[T] Deembed

FrequencyDomain

Considerations

SOLT Cal

•• Predicted ‘knownDUT’ Zo profilePredicted ‘knownDUT’ Zo profile

IFFT

Modeled

TDR

Measured


Circuits & Design32


•• InIn--fixture SOLT assumptions:fixture SOLT assumptions:–– Calibration using custom PWB standardsCalibration using custom PWB standards–– No standards correctionNo standards correction

•• Would requires modeling or another methodWould requires modeling or another method•• Will be examined in the futureWill be examined in the future

–– Data shown for test fixture with BEST results for Data shown for test fixture with BEST results for this procedurethis procedure

•• Optimal test pointOptimal test point•• Optimal Tline typeOptimal Tline type•• Optimal Tline lengthOptimal Tline length


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

Normalization

Time Gating

[T] Deembed

FrequencyDomain

Considerations

SOLT Cal


Circuits & Design33



TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

Normalization

Time Gating

[T] Deembed

FrequencyDomain

Considerations

SOLT Cal

•• SOLT vs. PredictedSOLT vs. Predicted


Circuits & Design34

TRL (THRU-REFLECT-LINE) Calibration•• InIn--fixture TRL/LRM assumptions:fixture TRL/LRM assumptions:

–– Calibration using custom PWB standardsCalibration using custom PWB standards–– Standards characterizationStandards characterization

•• THRU THRU –– NothingNothing•• REFLECT REFLECT –– NothingNothing•• LOAD LOAD –– Nothing (LRM Nothing (LRM –– Low Frequency)Low Frequency)•• LINEs LINEs –– ZZoo and Tand Tpdpd (TRL (TRL –– High Frequency)High Frequency)

–– Data shown for test fixture with BEST results for Data shown for test fixture with BEST results for this procedurethis procedure

•• Optimal test pointOptimal test point•• Optimal Tline typeOptimal Tline type•• Optimal Tline lengthOptimal Tline length


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

Normalization

Time Gating

[T] Deembed

FrequencyDomain

Considerations

SOLT Cal


Circuits & Design35



TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

Normalization

Time Gating

[T] Deembed

FrequencyDomain

Considerations

SOLT Cal

•• TRL/LRM vs. PredictedTRL/LRM vs. Predicted


Circuits & Design36

Normalization•• Normalization assumptionsNormalization assumptions

–– Calibration using uniform standardsCalibration using uniform standards–– Simple DUT/THRU measurementSimple DUT/THRU measurement–– Data shown for test fixture with BEST results for Data shown for test fixture with BEST results for

this procedurethis procedure•• Optimal test pointOptimal test point•• Optimal Tline typeOptimal Tline type•• Optimal Tline lengthOptimal Tline length


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

Normalization

Time Gating

[T] Deembed

FrequencyDomain

Considerations

SOLT Cal


Circuits & Design37

Normalization


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

Normalization

Time Gating

[T] Deembed

FrequencyDomain

Considerations

SOLT Cal

•• Normalization vs. PredictedNormalization vs. Predicted


Circuits & Design38

Enhanced Time Domain Gating•• Enhanced time domain gating assumptionsEnhanced time domain gating assumptions

–– Calibration using uniform standardsCalibration using uniform standards–– Data shown for test fixture with BEST results for Data shown for test fixture with BEST results for

this procedurethis procedure•• Optimal test pointOptimal test point•• Optimal Tline typeOptimal Tline type•• Optimal Tline lengthOptimal Tline length


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

Time Gating

Normalization

[T] Deembed

FrequencyDomain

Considerations

SOLT Cal


Circuits & Design39

Enhanced Time Domain Gating


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

Time Gating

Normalization

[T] Deembed

FrequencyDomain

Considerations

SOLT Cal

•• Enhanced Gating vs. PredictedEnhanced Gating vs. Predicted


Circuits & Design40

Microprobe LRM with Deembedding•• LRM with deembedding assumptionsLRM with deembedding assumptions

–– Calibration using microprobe Impedance Substrate Calibration using microprobe Impedance Substrate Standard (ISS)Standard (ISS)

•• LRM with automatic LOAD inductance LRM with automatic LOAD inductance compensationcompensation

•• ISS coplanar waveguide LOAD extremely good to ISS coplanar waveguide LOAD extremely good to high frequency with inductance compensationhigh frequency with inductance compensation

•• Eliminates any need for TRLEliminates any need for TRL–– DUT and test fixture measuredDUT and test fixture measured–– Test fixture modeledTest fixture modeled

•• Full 3D EM SolverFull 3D EM Solver•• Precise geometryPrecise geometry•• Known materialsKnown materials

–– Test fixture deembeddedTest fixture deembedded


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

[T] Deembed

Normalization

Time Gating

FrequencyDomain

Considerations

SOLT Cal


Circuits & Design41

Microprobe LRM with Deembedding


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

[T] Deembed

Normalization

Time Gating

FrequencyDomain

Considerations

SOLT Cal

•• Microprobe LRM/Deembed vs. PredictedMicroprobe LRM/Deembed vs. Predicted


Circuits & Design42

Comparison of All Techniques


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

[T] Deembed

Normalization

Time Gating

FrequencyDomain

Considerations

SOLT Cal

•• Insertion LossInsertion Loss


Circuits & Design43

Comparison of All Techniques


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

[T] Deembed

Normalization

Time Gating

FrequencyDomain

Considerations

SOLT Cal

•• Return LossReturn Loss


Circuits & Design44

Comparison of All Techniques•• InIn--fixture SOLT inaccurate, without detailed fixture SOLT inaccurate, without detailed

standards characterizationstandards characterization•• InIn--fixture TRL/LRM accurate and easy to fixture TRL/LRM accurate and easy to

implementimplement•• Simple normalization is inaccurate if the DUT Simple normalization is inaccurate if the DUT

has any significant reflectionshas any significant reflections•• Enhanced time domain gating accurate, but:Enhanced time domain gating accurate, but:

–– Reflection phase and band edges are inaccurateReflection phase and band edges are inaccurate–– Heavy user judgment and postHeavy user judgment and post--processing processing

involvedinvolved•• Microprobe LRM cal very accurate, but:Microprobe LRM cal very accurate, but:

–– Still must complete [ T ] matrix deembeddingStill must complete [ T ] matrix deembedding–– Determining error sDetermining error s--parameters can be very parameters can be very

difficultdifficult


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

TRL/LRM Cal

[T] Deembed

Normalization

Time Gating

FrequencyDomain

Considerations

SOLT Cal


Circuits & Design45

TRL/LRM Calibration Implementation


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

FrequencyDomain

Considerations

T Lines

Test Points

Cal Kit

Measurement

Standards

TRL/LRMCalibration

Implementation

• Choosing RF Test Points• Transmission Line Guidelines

• Making the Measurements• Configuring the Calibration Kit

• Designing PWB Standards


Circuits & Design46

Designing PWB Standards•• Necessary TRL/LRM StandardsNecessary TRL/LRM Standards


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

FrequencyDomain

Considerations

T Lines

Test Points

Cal Kit

Measurement

Standards

LOAD dPerfect 50 Ohms

REFLECT dOPEN or SHORT

THRU d d

LINE1 d dLong Length (low frequency)

LINE2 d dMid-Length (mid-frequency)

LINEX d dShort Length

(high frequency)

LAUNCH RECEIVEDUTd d

LAUNCH RECEIVEKnownDUT

d d


Circuits & Design47

Designing PWB Standards•• TEST FIXTURETEST FIXTURE

–– Each must be identical & same as standardsEach must be identical & same as standards•• THRUTHRU

–– Direct connection of launch/receiveDirect connection of launch/receive•• REFLECTREFLECT

–– Can be OPEN or SHORTCan be OPEN or SHORT–– Does NOT need to be perfectDoes NOT need to be perfect–– REFLECT must be the same for both portsREFLECT must be the same for both ports

•• LOADLOAD–– Must be perfect matchMust be perfect match–– Only achievable at low frequencyOnly achievable at low frequency

•• Known DUTKnown DUT–– Used to validate calibrationUsed to validate calibration


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

FrequencyDomain

Considerations

T Lines

Test Points

Cal Kit

Measurement

Standards

DUTd d

d d

d

d

KnownDUT

d d


Circuits & Design48

Designing PWB Standards•• LINEsLINEs

–– Any LINE length has invalid frequency rangesAny LINE length has invalid frequency ranges–– Numerical difficulties deriving Numerical difficulties deriving γ γ = = α α + j+ jΒ Β occur occur

when the wave phase at the reference plane when the wave phase at the reference plane approaches n*180approaches n*180oo, where n = 0, 1, 2, 3, …, where n = 0, 1, 2, 3, …

–– For 0For 0--20 GHz, one LINE length will not be enough20 GHz, one LINE length will not be enough–– Must use LOAD at low frequency (LRM)Must use LOAD at low frequency (LRM)–– Must design multiple LINEs for high frequenciesMust design multiple LINEs for high frequencies


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

FrequencyDomain

Considerations

T Lines

Test Points

Cal Kit

Measurement

Standards

n=1

n=2

Etc.


Circuits & Design49

Designing PWB Standards•• LINEs LINEs –– Calculating LengthsCalculating Lengths

–– Must know the prop velocity of the LINEs (Must know the prop velocity of the LINEs (vv))–– Must know phase span of interest (Must know phase span of interest (spanspan))

•• 180180o o * n (n=0,1,2,3…) is bad* n (n=0,1,2,3…) is bad•• Keep span < 140Keep span < 140oo (20(20oo--160160oo, 200, 200oo--340340oo, etc.), etc.)•• Tightening the span will increase accuracyTightening the span will increase accuracy

–– Must know one of the following frequencies:Must know one of the following frequencies:•• Low frequency (Low frequency (fflolo))•• Center frequency (Center frequency (ffcc))•• High frequency (High frequency (ffhihi))


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

FrequencyDomain

Considerations

T Lines

Test Points

Cal Kit

Measurement

Standards

...5,3,1=n( )

±×

××=

290

90spann

nfflohic

( )

×

±××=

n

spannff c

lohi 90

290

××

=

36090 n

fvxc


Circuits & Design50

Designing PWB Standards•• LINEs LINEs –– LINE length calculation exampleLINE length calculation example

smcv

r

88

105.14103 ×=×==

ε


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

FrequencyDomain

Considerations

T Lines

Test Points

Cal Kit

Measurement

Standards

•• Notes:Notes:–– Can iterate example above…next LINE fCan iterate example above…next LINE fhihi=5.72 GHz=5.72 GHz–– Using n=1 will give the widest bandwidth per LINEUsing n=1 will give the widest bandwidth per LINE–– Using n>1 allows longer LINEs to be used at higher frequency…canUsing n>1 allows longer LINEs to be used at higher frequency…can

be more accuratebe more accurate

Assumptions:LINEs in stripline FR4 (εr=4.0), Phase span = 100o, fhi = 20 GHz, n=1

GHzGHzspanff hic 86.12

210090

9020

290

90 =

+×=

+×=

mfvxc

39

8

1092.236090

1086.12105.1

36090 −×=

×

×=

=

GHzGHz

span

ff chi 2090

210090

86.1290

290

=

+×=

+×=GHzGHz

span

ff clo 72.590

210090

86.1290

290

=

−×=

−×=


Circuits & Design51

Transmission Line Guidelines•• TRL calibration cannot recover DUT TRL calibration cannot recover DUT

response if too much information is lostresponse if too much information is lost–– At high frequency, VNA & cables already have At high frequency, VNA & cables already have

some degree of losssome degree of loss–– Must choose launch/receive transmission lines so Must choose launch/receive transmission lines so

that loss is not too much worsethat loss is not too much worse


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

FrequencyDomain

Considerations

T Lines

Test Points

Cal Kit

Measurement

Standards

Pre-Calibration


Circuits & Design52

Transmission Line Guidelines•• Rule of Thumb Rule of Thumb –– Design THRU so that insertion Design THRU so that insertion

loss (test pointloss (test point--toto--test point) is no less than 0.707 test point) is no less than 0.707 ((--3 dB) at highest frequency of interest3 dB) at highest frequency of interest–– Keep traces short and use low loss dielectricKeep traces short and use low loss dielectric–– Keep traces wide (also keeps Zo consistent)Keep traces wide (also keeps Zo consistent)


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

FrequencyDomain

Considerations

T Lines

Test Points

Cal Kit

Measurement

Standards

Good Cal

Pre-Cal Loss Test for TRL Accuracy:VNA/Cable loss budget: -3 dBTHRU loss budget: + -3 dB“Cutoff frequency (fcut)”: -6 dB

Fcut = frequency above which datawill become invalid for calibration(Typically seen as ‘wavy’ frequencydata…especially in reflected data)


Circuits & Design53

Transmission Line Guidelines•• Allow no coupling between test fixture Allow no coupling between test fixture

transmission linestransmission lines–– Challenging when measuring dense DUTsChallenging when measuring dense DUTs–– Stripline is better than microstripStripline is better than microstrip

•• Design transmission lines to match test Design transmission lines to match test equipment Zo (typically 50 Ohms)equipment Zo (typically 50 Ohms)–– TRL DOES allow measurement in ANY TRL DOES allow measurement in ANY

impedance environmentimpedance environment–– TRL calibration can automatically TRL calibration can automatically

renormalize results to 50 Ohmsrenormalize results to 50 Ohms


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

FrequencyDomain

Considerations

T Lines

Test Points

Cal Kit

Measurement

Standards


Circuits & Design54

Choosing RF Test Points•• Intrinsic propertiesIntrinsic properties

–– Density, cost, ease of use, ease of terminationDensity, cost, ease of use, ease of termination

•• Quality of cable interfaceQuality of cable interface–– Zo, IL, moding, variability, & mating cycle lifeZo, IL, moding, variability, & mating cycle life

•• Quality of PWB interfaceQuality of PWB interface–– Zo, IL, moding, & attachment repeatability (solder)Zo, IL, moding, & attachment repeatability (solder)


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

FrequencyDomain

Considerations

T Lines

Test Points

Cal Kit

Measurement

Standards

TermCable


Circuits & Design56

Choosing RF Test Points•• Tyco has examined over 50 familiesTyco has examined over 50 families


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

FrequencyDomain

Considerations

T Lines

Test Points

Cal Kit

Measurement

Standards

•• Choose your own favorite…Choose your own favorite…


Circuits & Design57

Configuring the Calibration Kit•• Characterizing the standardsCharacterizing the standards

–– Measure transmission line impedances (TDR fine)Measure transmission line impedances (TDR fine)–– Measure each LINE propagation delay (TDT fine)Measure each LINE propagation delay (TDT fine)

•• LINE propagation delay is relative to the THRULINE propagation delay is relative to the THRU–– Calculate the valid frequency range for each LINECalculate the valid frequency range for each LINE

•• Calculated previously when board was designedCalculated previously when board was designed•• ReRe--calculate real values for increased accuracycalculate real values for increased accuracy


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

FrequencyDomain

Considerations

T Lines

Test Points

Cal Kit

Measurement

Standards

Example:20ps delay LINE, n=1, span=100o

Ghz

span

Delayfhi 4.19

3602

10090

10201

3602

901

12 =

+

××

=

+

×= −Ghz

span

Delayflo 6.5

3602

10090

10201

3602

901

12 =

−

××

=

−

×= −

( )...5,3,1,

3602

901 =

±×

×= n

spann

Delayf

lohi


Circuits & Design58

Configuring the Calibration Kit•• Preparing the VNA for calibrationPreparing the VNA for calibration

–– Can enter calibration constants directly into VNACan enter calibration constants directly into VNA–– Can use Cal Kit Manager to load from PCCan use Cal Kit Manager to load from PC

•• Freeware from Freeware from www.vnahelp.comwww.vnahelp.com


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

FrequencyDomain

Considerations

T Lines

Test Points

Cal Kit

Measurement

Standards


Circuits & Design59

Configuring the Calibration Kit•• Defining the standardsDefining the standards

–– C0C0--C3 and LOC3 and LO--L3 ARE NOT USED for TRL!L3 ARE NOT USED for TRL!–– ZZoo should be the same for each standardshould be the same for each standard


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

FrequencyDomain

Considerations

T Lines

Test Points

Cal Kit

Measurement

Standards


Circuits & Design60

Configuring the Calibration Kit•• Mapping standards to class assignmentsMapping standards to class assignments

–– Standard numbers are just arbitrary definitionsStandard numbers are just arbitrary definitions–– Must map standard numbers to known definitionsMust map standard numbers to known definitions


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

FrequencyDomain

Considerations

T Lines

Test Points

Cal Kit

Measurement

Standards


Circuits & Design61

Configuring the Calibration Kit•• Setting reference impedance and planesSetting reference impedance and planes

–– Line Zo relative to line, system Zo renormalizedLine Zo relative to line, system Zo renormalized–– THRU reference plane more accurateTHRU reference plane more accurate


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

FrequencyDomain

Considerations

T Lines

Test Points

Cal Kit

Measurement

Standards


Circuits & Design62

Making the Measurements•• Complete calibrationComplete calibration

–– Load calibration kit into the VNALoad calibration kit into the VNA–– Measure standards, as instructed by VNAMeasure standards, as instructed by VNA

•• Verify calibrationVerify calibration–– ReRe--measure standards to test repeatabilitymeasure standards to test repeatability–– Measure knownDUT to test accuracyMeasure knownDUT to test accuracy

•• Take measurementsTake measurements–– Connect two ports to desired DUT portsConnect two ports to desired DUT ports–– Terminate all other coupled portsTerminate all other coupled ports


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

FrequencyDomain

Considerations

T Lines

Test Points

Cal Kit

Measurement

Standards

for 0 where, jkaabS k

j

iij ≠==

bi is output wave on port iaj is incident wave on port jIncident waves on all other non-j ports is zero(meaning they are all matched impedance)

Terminate Terminate


Circuits & Design63

Making the Measurements•• Importance of terminationsImportance of terminations

–– Sharp error resonances will occur when coupled Sharp error resonances will occur when coupled paths in the DUT are not terminated properlypaths in the DUT are not terminated properly

–– Spikes caused by high reflections that take a long Spikes caused by high reflections that take a long time to return to the measurement porttime to return to the measurement port

•• Anything long in time is narrow in frequencyAnything long in time is narrow in frequency•• Anything short in time is broad in frequencyAnything short in time is broad in frequency


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

FrequencyDomain

Considerations

T Lines

Test Points

Cal Kit

Measurement

Standards


Circuits & Design64

TRL/LRM Success Stories


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

FrequencyDomain

Considerations

TRL/LRMCalibration

Success Stories

• Tyco HM-Zd PWB Footprint

•Tyco HM-Zd Connector•Tyco PT Connector (SFP/XFP Standard)


Circuits & Design65

Tyco HM-Zd PWB Footprint


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

FrequencyDomain

Considerations

•• Modeled vs. Measured (TRL/LRM)Modeled vs. Measured (TRL/LRM)


Circuits & Design66

Tyco PT Connector (SFP/XFP Standard)


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

FrequencyDomain

Considerations



Circuits & Design67

Tyco PT Connector (SFP/XFP Standard)


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

FrequencyDomain

Considerations

•• Time Domain: Measured TDR vs. Measured Time Domain: Measured TDR vs. Measured TRL/LRM TransformTRL/LRM Transform

TDR

IFFT

VNA


Circuits & Design68

Tyco HM-Zd Connector


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

FrequencyDomain

Considerations



Circuits & Design69

Tyco HM-Zd Connector


TRL/LRMCalibration

Implementation

TRL/LRMCalibration

Success Stories

In-FixtureTechnique

Comparison

FrequencyDomain

Considerations

•• Time Domain: Measured TDR vs. Measured Time Domain: Measured TDR vs. Measured TRL/LRM TransformTRL/LRM Transform

TDR

IFFT

VNA


Circuits & Design70

A Final Thought

•• Full 3D EM modeling becoming more prevalentFull 3D EM modeling becoming more prevalent–– Multiple packages can be purchasedMultiple packages can be purchased–– Having a tool DOES NOT guarantee accuracyHaving a tool DOES NOT guarantee accuracy

•• SS--parameter test data is becoming standardparameter test data is becoming standard–– Obtaining high frequency DUT data is challengingObtaining high frequency DUT data is challenging–– TRL/LRM calibration combines accuracy & practicalityTRL/LRM calibration combines accuracy & practicality

•• CAN ONLY BE SURE OF RESULTS WHEN MEASURED CAN ONLY BE SURE OF RESULTS WHEN MEASURED AND MODELED DATA OVERLAY!!!AND MODELED DATA OVERLAY!!!


Circuits & Design71

Further Information•• Presentation copies can be obtained from:Presentation copies can be obtained from:

– Chad Morgan, (717) 986-3342, [email protected]

– Dave Helster, (717) 986-5686, [email protected]

– Alex Sharf, (717) 986-5447, [email protected]

•• Tyco Electronics Circuits & DesignTyco Electronics Circuits & Design

Connector modeling & design

High-speed measurement & analysis

Gigabit system simulation & optimization

• For further information, email [email protected] or go to www.tycoelectronics.com/products/simulation

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