Concepts and features
R&S
®
ZNB/ZNBT
217
User Manual 1173.9163.02 ─ 62
C
G
R
L
Balun
Differential Matching Network
In contrast to standard balanced embedding (4-port), the matching circuit is only
applied to the differential mode port (2-port). It can be specified via a Touchstone s2p
file or by parametrizing a lumped "Shunt L, Shunt C" element model.
4.6.2.9
Fixture modeling and deembedding
When performing tasks such as verifying digital high-speed signal structures on printed
circuit boards (PCBs), measurements have to be carried out on certain layers without
the effects of probes, probe pads, vias, lead-ins and lead-outs. This requires the use of
accurate deembedding algorithms to calculate and remove these effects from the mea-
surements, leaving only the result for the area of interest.
Instead of asking the user to define the fixture by parametrizing one of the given lum-
ped circuit models or by "somehow" providing a suitable
snp
file, the firmware of the
R&S
ZNB/ZNBT now also provides integration for third-party tools that model the test
fixture from measured data:
●
AtaiTec's
(ISD)
●
PacketMicro's
●
Eazy de-embedding based on IEEE 370
The tools are integrated into the deembedding functionality of the R&S
ZNB/ZNBT
firmware. More fixture modeling tools may be added in future firmware releases.
Test Setup
The setup below shows an example for verifying the high-speed differential signal lines
on a PCB.
Offset parameters and de-/embedding
