Conductor type
Microstrip
crossection of the pcb conductor
Source rise time
ns
Source voltage
V
Length of parallel routes (L)
in
Substrate height (H)
mil
Trace Spacing (S)
mil
Substrate dielectric
Results
Coupled voltage
V
Crosstalk Coefficient
dB

Omni's crosstalk calculator is a simple tool that allows you to understand the crosstalk definition and calculate some crosstalk solutions for your circuit. Are you interested in discovering "What is crosstalk?" Then read on.

If, however, you're looking for the numerical crosstalk solutions to your circuit, to the left you have the calculator. If you have any questions about how to use it, take a trip to the "How to use the crosstalk calculator" section below.

What is crosstalk? Understanding the concept

Before we dive into using Omni's crosstalk calculator, we need to understand what is crosstalk. And before we do that at a technical level, we should understand what crosstalk is at a simple, more casual level.

Imagine a crowded room (bare with me, it's just a Covid-less hypothetical); maybe it's an official reception, or maybe it's just a concert about to start. In either situation, what you have is a lot of people talking to each other.

Aside from the lack of social distancing, the biggest problem is understanding the person you're talking to over everyone else's voice. Even if they are not exactly shouting in your ear, and even if you can still have your conversation without a problem, the amount of background noise is annoying.

This is precisely what crosstalk is. Applied to electronics, crosstalk is the interference created in one of the communication lines due there being one or more line of communication present. Its effects can range from imperceptible noise added to the signal up to total disruption of the original message. There are ways to prevent crosstalk; some might call them "crosstalk solutions". The gist of them is to try and electrically (and physically) separate your communication lines as much as possible.

Crosstalk definition - let's get technical

Now that you understand what crosstalk is at a basic level, let's dig a bit deeper into the technical side. We will start with the crosstalk definition and then move on to causes of it as well as some crosstalk solutions. Consider this section to be "What is crosstalk?" version 2.0. Just remember that we are talking about electrical crosstalk, which affects mostly Alternate Current (AC) circuits.

Omni's crosstalk definition is then:

Crosstalk is any phenomenon by which a signal transmitted on one circuit or channel of a transmission system creates an undesired effect in another circuit or channel.

You can see that it is a more technical and accurate description of crosstalk, but it is essentially the same idea we presented in the previous section. The technical crosstalk definition expands the meaning of crosstalk from pure signal integrity to any undesired effect caused by another transmission line in the circuit.

These "other effects" are typically caused by capacitive, inductive, or conductive coupling between the two circuits. It is, therefore, essential to know the characteristics of both your circuits. In particular, things like cable impedance can become crucial when designing an efficient and safe circuit.

This is only relevant in applications where multiple transmission lines are together, which, to be honest, is most real world applications. Think about your internet cable, which might come into your house next to the electrical system, the TV signal... and might even share a socket with electrical outlets in some cases.

One of the most common places to find crosstalk, however, is in PCB circuits, due to the proximity in which designers place the conductors. In such circuits, it is crucial to consider crosstalk and deploy some kind of crosstalk solution to try and minimize it.

It is to such purpose that we have created a collection of PCB calculators like the PCB impedance calculator and the RF unit converter, amongst others. You can find them all in the Tech and electronics calculators section.

How to use the crosstalk calculator? - A.K.A. getting those sweet crosstalk solutions

So we are now ready. Now that we have explained everything thoroughly, we are finally ready to use this calculator and understand whatever it throws at us. Don't worry though, as using this Omni calculator is very simple as you can see in the step-by-step guide we have prepared:

  1. Select the type of conductor you are using on your PCB.
  2. Be amazed at how the calculator shows/hides exactly the variables you need for each case.
  3. Fill in the fields under the image and above the "results" tab.
  4. Confirm you input the data in the right units (we have auto-conversion, so don't worry).
  5. Get your crosstalk solutions, both the coupled voltage and crosstalk coefficient.
  6. Go back to the top of the text and leave feedback on the crosstalk calculator so that we can enjoy the work done or improve, whichever applies.

Easy, right? Hopefully so. Just remember that if you are trying to design the best PCB circuit, we have other useful calculators for your project, like the PCB trace width calculator, PCB trace current capacity calculator and the PCB trace resistance calculator, to name a few.

We hope you enjoyed Omni's crosstalk calculator, and we hope to keep helping you with your projects and calculations!

Álvaro Díez