Most electrical engineers probably are aware that connecting the ground connection for ordinary oscilloscope probes to the wrong part of an ac power line will invite a lot of trouble. Unfortunately the remedies sometimes employed to head off difficulties can cause their own woes. In a lab where I was once employed, the instrument carts […]
FAQ
What does electrochemical impedance spectroscopy have to do with Li-ion health?
Electrochemical impedance spectroscopy (EIS) can be used for estimating the power delivery capability and state of health (SoH) of Li-ion batteries. It is important because it has the potential to improve rapid and accurate SoH monitoring of Li-ion batteries and support more sustainable battery storage systems for electric vehicles (EVs) and grid-scale energy storage systems.…
What causes signal attenuation in a PCB and how can it be controlled?
Except for the most basic designs, system clock rates are inexorably creeping upward across a wide range of applications, from 5G telephony to automotive advanced driver assistance systems (ADAS), medical, industrial, and mil/aero systems. As frequencies rise into the GHz range, the need for impedance control to minimize signal attenuation and protect signal integrity gets […]
Teardown: Amazon 4th generation Echo Dot
One of the latest incarnations of the Echo Dot boasts premium sound and an ability to pair up with Fire TV devices for a home theater audio experience. Construction-wise, there are usually a few changes from one generation of Echo devices to the next, and sometimes between early and later models of the same generation. […]
When to filter, attenuate, and equalize signals
Signal chain management is important in various applications like medical imaging, 5G communications, advanced driver assistance systems (ADAS), and a range of consumer, industrial, and military devices. Filters, attenuators, and equalizers are some of the tools designers have available to optimize signal chain operation. This FAQ begins by looking briefly at the definition of decibels […]
Optical attenuators and loopbacks, what’s the difference?
Fiber optic attenuators (optical attenuators) are used to reduce or control the energy of optical signals. They are used in optical communications systems to protect sensitive receivers or to modulate signals and for engineering evaluation, testing, and system validation. This FAQ reviews the basic operation of optical attenuators, looks at practical applications for optical attenuators, […]
Why use attenuators in quantum computers?
Quantum computers are cryogenically cooled because their quantum bits (qubits) are extremely delicate and sensitive to disruptions from even minute amounts of thermal noise, such as Johnson-Nyquist (J-N) noise. J-N noise is generated by the thermal agitation of electrons, regardless of any applied voltage, when the conductor is at equilibrium. Even small amounts of J-N […]
How to control dc microgrids
Microgrids are a great way to power locations where grid connections are unreliable, though it can be tricky to control them in robust ways. Daniel Zammit, Dept. of Industrial Electrical Power Conversion, University of Malta Microgrids get a fair amount of press coverage these days thanks to their role in distributed power generation. A typical […]
A better way to handle dc-dc converter hold-up times
Converters with built-in holdup circuitry reduce the size and requirements for input capacitors. Dr. André Buffing, L. Dinkelmann, Traco Power DC/DC converters are generally designed to maintain their output despite brief interruptions of their input power. The duration of this output hold-up often is set by the value of an external capacitor connected across the […]
Teardown: IOGEAR Smart USB-C 100-W GaN fast charger
YouTube has several videos featuring really bad designs for fast phone chargers. YouTubers doing these videos often point to problems such as transformers with chintzy insulation, line capacitors that lack the correct safety rating, and even chargers with plastic cases that heat up so much that they actually melt when there’s a heavy load. Fortunately, […]