Presented by:

Sergey Volkovich

Vladimir Dibnis

Fall 2011

Supervisor:Mony Orbach

To research high speed channels phenomena on the gen. 2 board

To find the correlation between the measurements, theory and simulation

Agilent Infiniium Scope

PC simulations

Phenomena Creation

Environment

Altera DE2 Board

Gen.2 Board

DC Power Supply GUI

Studying the project environment

Analyzing and measuring the signals from the crystal to the transmission lines

Building simulation models for each line and performing the simulations

Analyzing, measuring and simulating the lines with the resistive, capacitive and inductive mismatches. Finding the correlation between them and deriving conclusions

Analyzing, measuring and simulating crosstalk line. Finding the correlation between them and deriving conclusions

Summarizing the results and writing the project book

0 01 221 12

2 0 0 1 0

12 210 0

2

S L

L

SL

L S

R Z Z ZV V

V Z R V Z Z

RZT T

Z Z R Z

Time [ns]0-TpTp-2Tp2Tp-3Tp3Tp-4Tp4Tp-5Tp5Tp-6Tp6Tp-7Tp7Tp-8Tp8Tp-9Tp

Square Input's V in comparison [%]NANA25.695.615.611.551.251.2525.69

Square Input's V out comparison [%]NANANA13.502.932.9315.273.203.20

Time [ns]0.00Tp2Tp3Tp4Tp6Tp

Pulse Input's V in comparison [%]0.00NA13.25NA17.34NA

Pulse Input's V out comparison [%]NA3.07NA13.52NANA

( )Error= 100-100

( )i

i

Measurement t t

TheoreticalValue t t

,

, 1

,

, 1

( )

( )100-100

( )

( )

p p simulation i

p p simulation i

p p measurement i

p p measurement i

V t t

V t tError

V t t

V t t

Time [ns]0-TpTp-2Tp2Tp-3Tp3Tp-4Tp4Tp-5Tp5Tp-6Tp6Tp-7Tp7Tp-8Tp8Tp-9Tp

Square Input's V in comparison [%]NANANA0.0042.80NANANANA

Square Input's V out comparison [%]NANANA11.650.00NANANANA

Time [ns]0.00Tp2Tp3Tp4Tp6Tp

Pulse Following Amplitudes Relations [%]6.2813.0221.51166.67NANA

High correlation between theory, measurements and simulation at the amplitude and time domain

Overshoots and undershoots at low voltages

Ringings

General offset of -3mV at some lines

Rise time is slower than fall time, maybe due to the amplifier characteristics or ground capacitance

The signal fading in the simulation is much smaller than in the measurements

0, 0,

0, 0,

0, 0,

0, 0,

3. t=2TP,

5. t=3TP,

7. t=5TP,

9. t=6TP,

source reflected charging

source reflected charging

source reflected discharging

source reflected discharging

V V V

V V V

V V V

V V V

00 1 0( )

t

V t V V V e

( )Error= 100-100

( )i

i

Measurement t t

TheoreticalValue t t

Measurement and theory comparison for square input-

123456789

Square Input's t,in error comparison [%]NA0,0012,0013,647,416,789,296,770,00

Square Input's Vout error comparison [%]NA36,6843,89

Measurement and simulation comparison for square input-

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Square Input's t,in error comparison [%]NA12,5013,3310,457,416,789,296,770,00

Measurement and theory comparison for pulse input-

1234567

Pulse Input's t,in error comparison [%]NA0,0021,7412,0012,9416,000,00

Pulse Input's t,out error comparison [%]4,767,275,710,00

1234567

Pulse Input's t,in error comparison [%]NA30,0030,4310,6715,2915,000,00

Pulse Input's t,out error comparison [%]4,7612,7314,290,00

Measurement and simulation comparison for pulse input-

Time constant τ comparison for measurement, theory and simulation-

1

max min

0 min

ln 1V V

TV V

theory [ns]5,00

measurement charging [ns]6,37

measurement discharging [ns]8,38

measurement pulse [ns]7,25

simulation charging [ns]4,89

simulation discharging [ns]12,73

τ simulation pulse [ns]8,28

The most interesting phenomena that were analyzed were in the time domain

There was a high correlation between the theory, measurements and simulation at all of the three measured lines including the time constant

Similar to what we saw at the resistive termination the signal fading at the simulation is much smaller than at the measurements. other than that there’s excellent correlation between the simulation and the theory

0

( )(1 )t

I F IV t V V V e

L

Z

1. The beginning of the measurement2. Continuation of charging due to the return

wave3. The reflected waves arrives to the line

entrance4. The reflected wave changes it’s sign5. The input voltage changes it’s sign6. Continuation of discharging due to return

wave

Measurement and theory comparison for square input-

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Square Input's t,in error comparison [%]NANA5.715.064.76NA7.785.910.00

Square Input's Vin error comparison [%]0.003.980.000.0044.0711.4413.9312.212.58

Square Input's t,out error comparison [%]3.122.446.455.004.670.43

Square Input's Vout error comparison [%]NA1.79NANA0.14NA

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Square Input's t,in error comparison [%]NA4.065.717.595.710.748.897.530.00

Square Input's t,out error comparison [%]3.120.0011.295.004.670.43

Measurement and simulation comparison for square input-

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Pulse Input's t,in error comparison [%]NA4.260.0013.166.179.83NANA0.00

Pulse Input's t,out error comparison [%]0.902.381.057.14NA0.13

Pulse Input's Vout error comparison [%]NANA0.0035.79NANA

Measurement and theory comparison for pulse input-

Measurement and simulation comparison for pulse input-

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Pulse Input's t,in error comparison [%]NA25.5343.4811.8411.1118.95NANA0.00

Pulse Input's t,out error comparison [%]0.907.1415.7912.504.460.13

Time constant τ comparison for measurement, theory and simulation-

1

maxln 1 I

F I

V VT

V V

τ theory [sec]=2.00E-09

τ measurement discharging [sec]=1.25632E-09

τ measurement charging [sec]=1.54116E-09

τ measurement pulse [sec]=1.64953E-09

τ simulation discharching [sec]=2.45998E-09

τ simulation charching [sec]=2.45998E-09

τ simulation pulse [sec]=2.42187E-09

The main reason for the deviation between the measurements and the theory/simulation is the non-ideal nature of the coil

There is an 0.5ns delay between the measurements and the theory

The rise time is slower than the fall time, similar to what we have seen at the resistive mismatches

There’s a good compatibility in the order of the magnitudes between the time constants

The amp model that was constructed for the simulation did not express the Tfall, Trise and Tflat parameters for the pulse input

Similar to what we saw at the resistive termination the signal fading at the simulation is much smaller than at the measurements

Zs

Zo

Zo

Zo

Zs

Zo

Zo

Zo

ICmLm

near

far

near

far

ILm

LmCmfarLmCmnear IIIIII

TD

2TD

~Tr

~Tr

far end crosstalk

Near end crosstalk

Zo

V

Time = 2TD

ZoNear end current

terminated at T=2TD

V

Time = 0

Zo

Near end crosstalk pulse at T=0 (Inear)

Far end crosstalk pulse at T=0 (Ifar)

Zo

ZoV

Time= 1/2 TD

ZoV

Time= TD

Zo Far end of current terminated at T=TD

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Square Input's t near comparison [%]NA16.672.874.015.667.764.996.770.00

Square Input's t far comparison [%]3.4113.6310.915.153.081.550.36

Square Input's V near comparison [%]NA3.823.82NANA12.4112.41NANA

Square Input's V far comparison [%]NA82.12NANA89.71NANA

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Square Input's t near comparison [%]NA16.671.761.695.666.902.864.170.00

Square Input's t far comparison [%]0.007.1411.436.533.682.130.00

Square Input's V near comparison [%]NA1.961.96NANA14.2914.29NANA

Square Input's V far normalized comparison [%]NA6.67NANA7.64NANA

Measurement and theory comparison for square input-

Measurement and simulation comparison for square input-

Measurement and theory comparison for pulse input-

Measurement and simulation comparison for pulse input-

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Pulse Input's t near comparison [%]NA14.2920.0018.182.685.705.907.350.00

Pulse Input's t far comparison [%]0.736.278.2912.6813.5316.630.08

Pulse Input's V near comparison [%]NA18.2511.62NANA16.799.00NANA

Pulse Input's V far comparison [%]NA13.82NANA35.91NANA

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Pulse Input's t near comparison [%]NA14.2960.0036.363.921.6911.4512.330.00

Pulse Input's t far comparison [%]0.000.002.9413.1618.6012.770.00

Pulse Input's V near comparison [%]NA17.5027.03NANA157.14140.00NANA

Pulse Input's V far normalized comparison [%]NA84.52NANA6.61NANA

There is a high correlation between the measurements, theory and simulation at the time domain

There is an overshoot in the pulse simulation at the near end which affects the measured values

The theoretical calculation of the voltages at the near and far ends is based on the line’s parameters, such as mutual and self capacitance and inductance. Inaccuracy in them may cause a worse correlation

There is a high correlation between the measurements, theory and simulation

Higher correlation was found for square inputs

At lines with conductive and capacitive termination we focused at the time domain and the time constant due to their exponential nature

The following phenomena were noticed at the measurements: bias voltages, noises, different rise and fall speeds

The wave’s voltage decay at the simulation was much lower than in the measurements

Mixing analog and digital components isn’t recommended from the point of view of the simulation

There is a high correlation in the analysis from the crystal to the transmission lines between the measurements and the expected values of the voltages according to the theory and the datasheets