[SI-LIST] Re: How to measure the resistance, inductance and capac itance parasitic of a packaged chip?

  • From: "Clewell, Craig" <Cclewell@xxxxxxxxxxxxx>
  • To: "'jamesh235914@xxxxxxxxx'" <jamesh235914@xxxxxxxxx>
  • Date: Mon, 27 Aug 2007 13:16:01 -0400

 James, 

For low frequencies I believe you could use a smith chart as long as your
DUT is less than a quarter wavelength at the frequency of interest.  Use a
short for the inductance and an open for the capacitance.  L would be equal
to the imaginary portion of the measurement from the smith chart divided by
2pi*f.  The capacitance is equal to 1 / (reflection coefficient*2pi*f).
These equations assume that the VNA reading is not normalized.  If the DUT
has significant losses, or the frequency gets too high the trace on the
smith chart will start to spiral inward because the impedance is no longer
purely imaginary making this method worthless.

You may be able to get more accurate measurements if you create two
identical structures that vary only in length.  This will help to reduce the
affects of the vias, probes, pads, etc if the paracitics of these things are
significant compared to the DUT.  If you use 2 structures you can take the
difference in the measured parasitics divided by the difference in the
length which will yield the L or C per unit length.

There may be other methods, but thought I  would just throw this out there
to chew on.

CC

-----Original Message-----
From: James H [mailto:jamesh235914@xxxxxxxxx] 
Sent: Monday, August 27, 2007 11:38
To: si-list@xxxxxxxxxxxxx
Subject: [SI-LIST] How to measure the resistance, inductance and capacitance
parasitic of a packaged chip?

Dear All,


I am studying how to measure the resistance, inductance and capacitance
parasitic of a packaged chip. What is the best method to model and measure
the parasitic of a chip+package? If I get S11 parametric by one port
measurement, how could I use S11 parametric fit to get the resistance,
inductance and capacitance value?



Thanks & Best Regards,

 H


------------------------------------------------------------------
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:
//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:     
                //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
  

|**************************************************************************|
This email is intended only for the person or entity to which it is
addressed and may contain confidential, proprietary and/or privileged
material. Any review, distribution, reliance on, or other use of this
information by persons or entities other than the intended recipient is
prohibited. If you receive this message in error, please immediately notify
the sender and delete it and all copies of it from your system. Thank you.
|**************************************************************************|
------------------------------------------------------------------
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:
//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:     
                //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:

  • » [SI-LIST] Re: How to measure the resistance, inductance and capac itance parasitic of a packaged chip?