August 2023 Archives - In Compliance Magazine

Pre-Compliance EMI Testing

Pre-compliance testing saves time and costs by detecting potential problems early in the design process. The use of appropriate tools and techniques improves the chances of passing the full compliance test on the first try.

(Re)Discovering the Lost Science of Near-Field Measurements, Part 2

This article is the third in a series commemorating 70 years since the advent of modern EMI testing. But this last article is itself divided into multiple parts, due to the topic’s complexity. Unlike the previous two articles, which mainly tracked evolution and explained issues, this series of installments argues that we started off correctly seventy years ago, but then took the wrong fork in the road in 1967.

Clock Duty Cycle Tuning for Desense Mitigation in Modulation‑Involved Cases

This paper provides a comprehensive study on how to mitigate desense with the change in the spectrum distribution by tuning the duty cycle of the interfering clock. Measurements conducted on a real cellphone showed a 10 dB suppression of desense for certain TX bandwidth condition.

The Legal Perils of Customer Service

Customer service, before and after sale, is one of the most important functions that must be performed by a manufacturer or product seller. It is also one of the riskiest. Obtaining no information, inadequate information, wrong information, misleading information, or harmful information can make it difficult to evaluate future risk, meet your regulatory obligations, and defend a product liability lawsuit.

Return-Current Distribution in a PCB Microstrip Line Configuration, Part 1

This is the first article of a two-article series devoted to the return current distribution in a 2-layer FR-4 PCB microstrip line configuration with a solid reference plane.

Can Electrostatic Discharge Design Problems Be Solved with Electronic Design Automation Tools Alone? Part 1

Going back several decades, Electrostatic Discharge (ESD) design and layout checks that were done manually were laborious and time-consuming, let alone not confidently reliable.

Locating the Noise Source of the 10-30 MHz “Hump”

During conducted emission tests, one of the challenges manufacturers face is the resonance peaks in the harmonic noise somewhere between 10 MHz and 30 MHz. Often, no amount of filtering will eradicate or attenuate the peak.

Cavity Resonances of Shielding Boxes and Cans

Many years ago, the author experimented on a metal enclosure of one of his company’s main products. The experiment involved placing an electric field probe inside the empty metal enclosure (no electronics inside) and applying 10 V/m using the IEC 61000-4-3 radiated RF immunity test system.

Questions to Ask Before Purchasing a TEM Cell or GTEM Cell

When it comes to conducting electromagnetic compatibility (EMC) testing, TEM (Transverse ElectroMagnetic) cells and GTEM (GigaHertz Transverse ElectroMagnetic) cells are widely used for their ability to generate controlled and repeatable test environments.