According to a press release issued by the FCC last month, the company, Truphone, failed to disclose individual investments of more than 5% of the company by Russian investors Alexander Abramov, Alexander Frolov, and Roman Abramovich…

as it happened to you? When troubleshooting an electromagnetic interference (EMI) issue, you’ve tried various combinations of components and saw the signal of interest reduced. But another frequency signal unexpectedly raised above the limit line. Or, you introduced a chassis plane on your printed circuit board (PCB), only to find the radiated emissions became much worse instead of getting better. These are typical cases of “tuning the resonances of a circuit.”

Most EMI emissions are related to structural resonances. Structural resonances are also one of the main reasons that electromagnetic compatibility (EMC) can be mystifying. Unknowingly, engineers often spend days and months tuning the resonances of a circuit by adding passive elements such as inductors and capacitors. Sometimes, they are lucky enough to finally arrive at a combination that would give them a pass. But most of the time, solutions are hard to find.

IEEE and OPEN Alliance Standards and Testing

thernet solutions have been popular in industrial and computing applications for several decades but were not widely adopted in the automotive area. Automotive Ethernet enables fast and robust data communication, with high flexibility in bus topologies for multiple electronic control units (ECUs). This makes Ethernet technologies a potential candidate to provide high bandwidth, connectivity, and robust operation while accelerating the evolution of automotive networks from domain to zonal architecture.

In 2016, two standards, 100BASE-T1 and 1000BASE-T1, were drafted for the automotive industry. As of 2022 two additional standards, namely 10BASE-T1s and MGB-T1, are in development by the One Pair Ethernet Network (OPEN) Alliance committees. OPEN Alliance includes several technical committees for the standardization of Ethernet-based technologies in the automotive market. The Institute of Electrical and Electronic Engineers (IEEE) covers 100BASE-T1 and 1000BASE-T1 with the IEEE 802.3bw and IEEE 802.3bp standards. Both were adopted to serve specific automotive requirements, mostly related to electromagnetic compatibility (EMC).

he smart battery was hailed as an engineering marvel when it was first introduced in 1994 by Intel and Duracell. The heart is the system management bus, or SMBus, that tracks state-of-charge (SoC) and captures performance data. The SMBus also includes the battery management system (BMS) to assure the safe operation of Li-ion batteries by limiting over-voltage and preventing current overloads.

Unlike a regular battery in which the charger is in command, the smart battery is the host that controls the charge function in a Level 2 charger. Being the master enables charging future battery chemistries for which no charge algorithm currently exists. Level 3 is a hybrid charger accommodating batteries with SMBus protocol, as well as regular batteries. Level 3 is the preferred system as the charger charges regular batteries and takes control when SMBus communication fails. Level 1 chargers only supported a single chemistry and have been discontinued.

China’s Latest Regulation on 2.4 GHz and 5 GHz Equipment

MIIT 2021 No. 129 Updates China’s Requirements for Multiple Types of Radio Services

n October 13, 2021, the Ministry of Industry and Information Technology of the People’s Republic of China (MIIT) issued MIIT 2021 No. 129, “Notice on Strengthening and Standardizing the Radio Management of 2400 MHz, 5100 MHz, and 5800 MHz bands.” This regulation came into effect on January 1, 2022, with a two-year transitional period.

Scope

MIIT 2021 No. 129 applies to equipment operating in the 2400-2483.5 MHz, 5150-5350 MHz, and 5725-5850 MHz frequency bands which are allocated for multiple types of radio services, including fixed, mobile, radio navigation, fixed-satellite, earth exploration-satellite, satellite radiolocation, or space research applications. The 2400-2483.5 MHz and 5725-5850 MHz bands are also designated for industrial, scientific, and medical (ISM) applications that emit electromagnetic energy, which is subject to a different regulation. Radio stations or equipment do not have exclusive access to or use of the 2400-2483.5 MHz, 5150-5350 MHz, and 5725-5850 MHz frequency bands.

Concept of a Phasor in Sinusoidal Steady State Analysis

his article introduces a concept of a phasor which is extensively used in several EMC topics including electromagnetic waves, antennas, and transmission lines. The following series of articles will use phasors to determine voltages and currents along the transmission line, and subsequently the input impedance to transmission line.

1. Sinusoidal Voltages

any articles published in In Compliance focus on ESD design and testing methods. But there is a lot more to semiconductor reliability. ESD reliability is based on the understanding of the high current behavior of protection devices. Protection designs are implemented in the IC to meet the ESD targets. This approach is not feasible for most of the other semiconductor reliability phenomena. In contrast to ESD, the actual understanding and definition of semiconductor reliability for field applications is less precise. It requires the understanding of device physics and reliability models. These models are mostly established and allow with some confidence to predict the IC device lifetime during field applications. In this article, we will have a look at different reliability phenomena and models and their contribution to the overall semiconductor reliability. We specifically cite only three representative references here [1-3] although the literature has an immense amount of work on the different reliability aspects, especially exhaustively covered by the technical papers at the International Reliability Physics Symposium for the last five decades.