[SI-LIST] Re: TDR Analsis Equipment..Tektronix vs Agilent?

Hi,
The biggest problem in using a TDR or VNA for that matter is to get enough
energy into the DUT since even a very small inductance at the connection
point from the TDR to the DUT will give an insertion loss. It's possible to
get a return loss of -20dB at 5GHz if you work hard. At 50 GHz it's hard to
get -3 dB RL which means that half of the power will enter the DUT and the
rest is wasted. By using a VNA it is possible to make a TRL calibration kit
and remove the effect of the testsystem and only get the DUT
characteristics.
I use a short pigtail with a thin semirigid coax instead of a probe when I
do measurements with the TDR(tektronix). It increases the accuracy a great
deal.

BR
Peter

-----Original Message-----

From: si-list-bounce@xxxxxxxxxxxxx
[*mailto:si-list-bounce@xxxxxxxxxxxxx*<si-list-bounce@xxxxxxxxxxxxx>]
On Behalf Of ext Asbenson, Lyndell L

Sent: 24. april 2007 02:27

To: heidi.barnes@xxxxxxxxxx; si-list@xxxxxxxxxxxxx

Cc: timothy.j.nash@xxxxxxxx; tom_cip_11551@xxxxxxxxx

Subject: [SI-LIST] Re: TDR Analsis Equipment..Tektronix vs Agilent?

Dedicated TDR is much easer to setup then going the VNA route -Lyndell

-----Original Message-----

From: si-list-bounce@xxxxxxxxxxxxx
[*mailto:si-list-bounce@xxxxxxxxxxxxx*<si-list-bounce@xxxxxxxxxxxxx>
]

On Behalf Of Barnes, Heidi

Sent: Monday, April 23, 2007 12:17 PM

To: si-list@xxxxxxxxxxxxx

Cc: timothy.j.nash@xxxxxxxx; tom_cip_11551@xxxxxxxxx

Subject: [SI-LIST] Re: TDR Analsis Equipment..Tektronix vs Agilent?

Hi Tom,

Tim is correct in that probing is not a simple task. If you have the time
and patience, a Vector Network Analyzer with PCB Thru-Reflect-Line
Calibration standards can provide a method for getting measured electrical
data for a PCB structure that does not include the probes or connectorized
transitions on to the printed circuit board. The S-Parameter data can then
be converted to time domain for TDR analysis of the discontinuities and a
40GHz box will give you around an 18pS rise time pulse (an edge that is
~100mils long for a PCB dielectric constant of ~4) which gives a significant
amount of detail (50mils is rather ambitious unless you have money for the
top end 110GHz VNA's or 8pS rise time TDR scopes). The other thing to think
about is that most applications running about 3Gbps are differential so it
is also nice to have a 4-Port system for measurements.

Regards,

Heidi

-----Original Message-----

From: si-list-bounce@xxxxxxxxxxxxx
[*mailto:si-list-bounce@xxxxxxxxxxxxx*<si-list-bounce@xxxxxxxxxxxxx>
]

On Behalf Of Nash, Timothy J

Sent: Monday, April 23, 2007 11:33 AM

To: tom_cip_11551@xxxxxxxxx; si-list@xxxxxxxxxxxxx

Subject: [SI-LIST] Re: TDR Analsis Equipment..Tektronix vs Agilent?

Hi, Tom.

I have tried using a Tektronix TDR (I'm not sure of the model) to probe PCBs
before, and found that what probe you were using, and WHAT you were probing,
can make or break your measurement. We were using a hand-held
pressure-actuated type probe and simply bending your wrist a little would
change the response. We had a tough time even discerning between two vias
spaced an inch apart from each other. I believe the probes used by most PCB
manufacturers are on a robotic arm and they are probing PCB coupons that
have pre-defined TDR features. I found it very difficult to glean much
useful info from real PCB traces when the discontinuities were as close
together as what you are describing. I don't believe this was a fault of the
scope - just a function of the probing method and the feature constraints of
the PCB.

Tim





-----Original Message-----

From: si-list-bounce@xxxxxxxxxxxxx
[*mailto:si-list-bounce@xxxxxxxxxxxxx*<si-list-bounce@xxxxxxxxxxxxx>
]

On Behalf Of tom_cip_11551

Sent: Monday, April 23, 2007 10:47 AM

To: si-list@xxxxxxxxxxxxx

Subject: [SI-LIST] TDR Analsis Equipment..Tektronix vs Agilent?

Hi to the Signal Integrity community.

I am looking for a set of equipment with wich to do TDR analysis on=3D20
high speed PCB structures. We are now building boards to run at=3D20 speeds
of 3 Gb/s or faster and I would like to resolve=3D20 discontinuites within,
say, 50 mils to 80 mils of each other.

I have gotten quotes from Tektronix and Agilent for TDR equipment. =3D20

The Tektronix system consists of the DSA8200 digital sampling = scope,=3D20
the 80E04 TDR sampling module and the 80SICON signal integrity and=3D20
failure analysis software (a $20K item by itself).

The Agilent system consists of the 86100C scope, the 54754A TDR=3D20 module
and various other software programs for S parameters, Jitter=3D20 analysis,
etc.

I am wondering what the Signal Integrity community at large is=3D20 using.
Which system is more popular and, most important, cost=3D20 effective?

What are some of the advantages and drawbacks of each?

Are there other solutions on the market that are more cost effective?

Thank You

Tom



------------------------------------------------------------------

To unsubscribe from si-list:

si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field

or to administer your membership from a web page, go to:

*http://www.freelists.org/webpage/si-list*<http://www.freelists.org/webpage/si-list>

For help:

si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field



List technical documents are available at:

*http://www.si-list.net* <http://www.si-list.net/>

List archives are viewable at: =3D20

*http://www.freelists.org/archives/si-list*<http://www.freelists.org/archives/si-list>

or at our remote archives:

*http://groups.yahoo.com/group/si-list/messages*<http://groups.yahoo.com/group/si-list/messages>

Old (prior to June 6, 2001) list archives are viewable at:

*http://www.qsl.net/wb6tpu* <http://www.qsl.net/wb6tpu>

=3D20

------------------------------------------------------------------

To unsubscribe from si-list:

si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field

or to administer your membership from a web page, go to:

*http://www.freelists.org/webpage/si-list*<http://www.freelists.org/webpage/si-list>

For help:

si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field



List technical documents are available at:

*http://www.si-list.net* <http://www.si-list.net/>

List archives are viewable at: =3D20

*http://www.freelists.org/archives/si-list*<http://www.freelists.org/archives/si-list>

or at our remote archives:

*http://groups.yahoo.com/group/si-list/messages*<http://groups.yahoo.com/group/si-list/messages>

Old (prior to June 6, 2001) list archives are viewable at:

*http://www.qsl.net/wb6tpu* <http://www.qsl.net/wb6tpu>

=3D20

------------------------------------------------------------------

To unsubscribe from si-list:

si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field

or to administer your membership from a web page, go to:

*http://www.freelists.org/webpage/si-list*<http://www.freelists.org/webpage/si-list>

For help:

si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field



List technical documents are available at:

*http://www.si-list.net* <http://www.si-list.net/>

List archives are viewable at: =20

*http://www.freelists.org/archives/si-list*<http://www.freelists.org/archives/si-list>

or at our remote archives:

*http://groups.yahoo.com/group/si-list/messages*<http://groups.yahoo.com/group/si-list/messages>

Old (prior to June 6, 2001) list archives are viewable at:

*http://www.qsl.net/wb6tpu* <http://www.qsl.net/wb6tpu>

=20

------------------------------------------------------------------

To unsubscribe from si-list:

si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field

or to administer your membership from a web page, go to:

*http://www.freelists.org/webpage/si-list*<http://www.freelists.org/webpage/si-list>

For help:

si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field



List technical documents are available at:

*http://www.si-list.net* <http://www.si-list.net/>

List archives are viewable at:

*http://www.freelists.org/archives/si-list*<http://www.freelists.org/archives/si-list>

or at our remote archives:

*http://groups.yahoo.com/group/si-list/messages*<http://groups.yahoo.com/group/si-list/messages>

Old (prior to June 6, 2001) list archives are viewable at:

*http://www.qsl.net/wb6tpu* <http://www.qsl.net/wb6tpu>


------------------------------------------------------------------
To unsubscribe from si-list:
si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field

or to administer your membership from a web page, go to:
http://www.freelists.org/webpage/si-list

For help:
si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field


List technical documents are available at:
                http://www.si-list.net

List archives are viewable at:     
                http://www.freelists.org/archives/si-list
or at our remote archives:
                http://groups.yahoo.com/group/si-list/messages
Old (prior to June 6, 2001) list archives are viewable at:
                http://www.qsl.net/wb6tpu

Other related posts: