ANSI EIA-364-90-2000 pdf free download.Crosstalk Ratio Test Procedure for Electrical Connectors, Sockets, Cable Assemblies or Interconnect Systems.
21L2 Probes
Probes, when us&I, shall have siiitable rise time performance and circuit loading characteristics (eg. resistance and capacitance).
11.2 Method B, frequency domain
A network analyzer is piferrcd. When greater dynamic range s desired, a signal generator arid spectrum analyzer may aIteritivelv be used. An 8 port network analyzer or baliins may be used for differential measurements.
2.2 Fixture
Unless otherwise specified in the iferencing document the specimen environment impedance sh.all match the impedance of the test equipmcnt. Typically this will be 50 ohms for singk-ended measurernent.s ancJ 100 ohms for cUfferential.
2.2.1 Specimen conductor assignments
For each measurement, tht driven and quiet lines shall be fixtured as indicated in thc rcferencing document. Adjacent signal lines to these should likewise e terminated if possible (electricaliy long adjacent signa’ lines may resonate adding error to the resuks). Unless otherwise specified a 1:1 signal to ground ratio (one differatial pair to one ground if differential nieasuremens are performed) shall bc used with etch end having all grounds commoned, for an example, see figure A.4. The fixture should be designed with equal delays for all lines4
NOTE — When the drive signal is differential and not balanced, the common mode energy shall t terminated.
2.2.2 TerminaLlon
The far end uf the Linven lines and both ends of the quiet line shall be terminated in the specimen environment impedance specified usiTig one of the methods in figures A.2 and A3. Mttching networks may be used if the specimen environment impedance does not match that of the test equipment. Care should be taken to minimize the reactances of the resistive terminations over the range of test frequencies.
NOTE — ‘[he txture geomery and materials may impact the mcasurements due to the fixture paiasiücs. Usually the product’s intended use diciates the most meaningful way to fixture it.ANSI EIA-364-90 pdf download.