Number of wavelengths between signal via and ground return vias
returns the number of wavelength between signal via and ground returns vias at a
given frequency to analyze for resonant responses or structures. The critical
wavelength is given by the equation:
d — Center to center distance between signal via and ground via.
f — Operating frequency.
Er — Relative dielectric constant.
c — Speed of light.
You can use this function to quickly determine the maximum wavelength for a given layout. The consequences of exceeding a specified wavelength is given in .
Critical Wavelength of Single-Ended Via
Calculate the critical wavelength of a single-ended via at 20 GHz.
obj = viaSingleEnded; criticalwavelength(obj,20e9)
ans = 0.2067
via — Single ended via
Single ended via, specified as a
frequency — Frequency to calculate initial wavelength
scalar | vector
Frequency to calculate initial wavelength, specified as a scalar or vector integer in Hz.
n — Choice of signal via
1 (default) | positive scalar integer
Choice of signal via, specified as a positive scalar integer.
 Steinberger, Telian, Tsuk, Iyer and Yanamadala, “Proper Ground Via Placement for 40+ Gbps Signaling”, DesignCon 2022, April 2022.
 Ramo, Whinnery and Van Duzer, Fields and Waves in Communications Electronics, third edition, section 9.3, John Wiley and Sons Inc., copyright 1994
Introduced in R2023a