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Transitioning Stitching Vias - EMC Simulations
EMI failures can happen due to small, innocent mistakes. One specific issue, as shown in the picture, is the lack of return reference...

Dario Fresu
1 min read


The most important picture you need to see in EMI
This picture helped me bridge the gap between electronic theory and PCB design for EMC in practice. One of the hardest things I found...

Dario Fresu
1 min read


EMC - Common Mode Currents Through Parasitic Paths
Switched Mode Power Supply - EMI will catch you when you least expect it! It's always about them: Common-mode current! They always find a...

Dario Fresu
2 min read


EMC Design In Practice - Conducted Emissions
One of the final tests for your electronic design before it becomes available on the market will be the conducted emissions test....

Dario Fresu
1 min read


EMC in Practice: Conducted Emissions - SMPS
Here are several issues that can arise in your PCB Design if these things are not well taken care of. My hope is to help you see these...

Dario Fresu
2 min read


Digital Signals & Harmonics in EMC
This is why many PCB designs and electronic products fail EMC tests! Oversimplified? Maybe not. In the majority of cases, the problem is...

Dario Fresu
2 min read


Radiations from Differential mode currents
If you are failing the EMC test in Radiated Emissions, this will help you see why: The formula you see here describes the radiated...

Dario Fresu
2 min read


Shielding
Looks like an innocent mistake, but this can cause a great deal of EMI troubles. To put it simply, think about your chassis as acting...

Dario Fresu
1 min read


Radiations from Differential Mode Currents Ribbon Cables
In designing for EMC, details matter. A lot! A simple example is ribbon cables. Most often, to save on costs (only apparent), we cut down...

Dario Fresu
2 min read


Two Layers stackup with both signals layers
The first thing I look at when a client's project fails EMI: The Stackup! I like to think about the stackup as the foundation of a...

Dario Fresu
2 min read


Electrostatic Discharge - ESD
One of the most problematic EMI events for your product! It won't matter if you have a metal enclosure or a plastic enclosure; you always...

Dario Fresu
1 min read


Radiations from Common Mode Currents in PCBs
One of the toughest EMC issues you are likely to encounter when designing printed circuit boards is managing radiations from common mode...

Dario Fresu
2 min read


Subtle Design Mistakes in EMC
When your Printed Circuit Board (PCB) fails EMC tests, often the problem is not one big issue, but the compounding of many poor design...

Dario Fresu
1 min read


ESD - Chassis and Parasitic Capacitance
One of the classic ESD misconceptions is thinking: "We won't have Electrostatic Discharge problems; we connected the chassis to the...

Dario Fresu
2 min read


How to choose the stackup of the board.
Good EMC results start with a well-chosen stackup. Is it that simple? Almost. I like to think about EMC as the test which measures how...

Dario Fresu
2 min read


Signal Propagation in a PCB
This is one of the reasons why many hardware designers fail to pass EMC tests. This is also one of the hardest concepts I struggled with...

Dario Fresu
2 min read


EMC Design for PCBs: Be aware of using Power Planes as Return Reference Planes!
Back when I started designing PCBs I heard it was pretty common to use power planes as Return Reference Planes (RRP), and I still see...

Dario Fresu
2 min read


Radiated Emissions and Current Loops.
If current always flows in loops, how is it possible for a signal to propagate if the signal has not yet reached the load and the...

Dario Fresu
1 min read


How to reduce crosstalk in our PCB and reduce EMI?
Crosstalk can not only be a signal integrity problem, but it can also become a very painful EMI problem if noise couples from a trace to...

Dario Fresu
2 min read
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