Feedback is relevant not only to electronic circuits but also to all kinds of natural and human-based phenomena ranging from mechanical engineering to economics and finance. Feedback emerges when one or more system outputs are connected back to system inputs. If polarity is inverted, it is an instance of negative feedback, which in electrical circuits […]
FAQ
Basics of CMOS and measuring CMOS logic parameters
Complementary metal-oxide semiconductor (CMOS) fabrication uses p-type and n-type complementary and symmetrical pairs to implement logic functions. The fundamental building block of the CMOS circuit is the MOSFET semiconductor, which enables it to operate at far lower current levels than bipolar transistors. This current reduction comes via pairs of p-type and n-type MOSFETs connected gate-to-gate […]
Hysteresis and its measurement
Hysteresis might be defined as something that happens when the physical state depends upon its history. The classic example of hysteresis in action is the residential thermostat. It has built-in hysteresis to prevent rapid cycling. It’s low cut-in and high cut-out levels are designed to prevent the heating/cooling system from rapid switching, which would quickly […]
The hot and cold of thermocouples
The common temperature probe contains a thermocouple consisting of two dissimilar metals welded together to form an electrical junction. A voltage that varies with temperature is generated. Slightly less accurate than resistance temperature detectors (RTDs), thermocouples cover a wide temperature range and respond quickly. Combinations of different metals create different voltage responses. All dissimilar metals […]
Lasers and how to measure their output
Laser is an acronym for light amplification by stimulated emission of radiation. Lasers, of course, started out as comprised of discrete components. The most basic laser consists of a cylinder containing the lasing medium, a material that emits light when exposed to an outside source of energy. The gain medium can be gas, liquid, solid […]
Understanding electro-optic modulation
The electro-optic modulator is used to modulate a beam of light. Laser-controlled modulators are capable of operating in the gigahertz range, and modulation may be imposed on the amplitude, phase, or polarization of the beam. The component that makes this possible incorporates an element that exhibits an electro-optic effect, a change in its optical properties […]
Understanding and measuring optoelectronic oscillators
The problem with even a high-end electronic oscillator–such as a quartz crystal oscillator, dielectric resonator, sapphire resonator or air dielectric resonator–is that as the output frequency rises, excessive phase noise also rises. Optoelectronic oscillators are not subject to this and other dysfunctional high-frequency characteristics, and consequently they are suitable in certain exacting 21st century applications […]
Getting familiar with work-at-home instrumentation
The rise in social distancing has fostered a need for professional-grade test instruments that function as well at home as in the lab. David Horn | Digilent The events that have unfolded across the world since the beginning of 2020 have turned the global marketplace upside down. Few industries have felt this seismic shift as […]
Work-at-home tools: PC-based instruments address demanding applications
Advanced technology now lets budget-priced instrumentation handle tasks once requiring specialized and pricey test gear. Trevor Smith | Pico Technology Test & Measurement With a significant segment of engineers and researchers working at home or away from their lab during the pandemic, there is a large incentive to troubleshoot designs and validate performance using systems […]
Monitoring heart rate variability for better athletic ability
Sensors and sophisticated algorithms together deliver check heart-rate variability and other exercise metrics. Alisher Kholmatov, Recep Ozgun Micros, Security & Software Business Unit, Maxim Integrated From weekend warriors to professional athletes, most people who engage in regular sports activity take note of various factors that influence their performance. Some meticulously track certain metrics from game […]