Temperature is by far the most commonly measured physical parameter in industrial, commercial, and even residential settings. It’s obviously about much more than just “what’s the temperature, so I will know what coat to wear?” Temperature readings are needed to control processes and systems via a negative feedback loop, PID algorithms, and comparators (References 1 […]
basics
Common emitter circuit for analog signal amplification
Today’s microcontrollers are crammed with useful features that have obviated the need for going off chip in order to gain useful functionality. So-called “system-on-chip” or SoC platforms have streamlined product development cycles. They have done this by allowing engineers to spend more time focusing on value-added work and less time on the more mundane glitches […]
Radio receiver architectures, Part 1—TRF and Superhet
A transmitter has much-less challenging task than the receiver. The former operates on a higher-level, known signal in a known setting, while the latter must find and decode a largely unknown signal corrupted by internal and external noise, interference from other signals, distortion, low signal levels, and constantly changing parameters. This FAQ looks at the […]
Analog computing 2.0
Since the late 1970’s, digital technology has dominated the field of computing. Left behind for most applications was the analog computer, a tool that had existed in purely mechanical forms since ancient times (think the Antikythera mechanism, astrolabe or even the humble slide ruler). Before the digital revolution, analog computing offered a lot of promise […]
Practically speaking: 4-20mA current loops
In a world where digital it is all the rage thanks to the promises of concepts such as the Internet of Things, wearables, and augmented reality it’s easy to overlook just how relevant analog technology remains for many industries. Many engineers and technicians can appreciate that from a signals perspective digital signals are but a […]
Photodiode: light sources, the amount of light, and color
I have touched on light sensing methods and the amplification of the signals from them in the past, but at a more fundamental level, how do you choose one? What parameters are important? The answer depends, among other things, on the light source (focused or not), the amount of light and its color. Focused or […]
Practical points for Analog-to-Digital converters
Confusion often arises around the topic of criteria for picking analog-to-digital converters (ADC). Much discussion is usually given to the sampling rate (also referred to as the conversion rate) which dictates how frequently the source signal must be sampled per second to faithfully reproduce that signal. Twentieth-century electronic communications engineer Harry Nyquist answered that question […]
Amplifiers: What do rail-to-rail and single supply mean?
With respect to analog signals, a “rail” is a boundary that a signal has to work within. For a long time, operational amplifiers have required opposite but equal voltage supplies. If you see a dual-supply or dual-voltage op amp, it means that two supply voltages power the amplifier; the absolute supply voltage levels are the […]
IBIS model: How can it help with signal analysis?
An Input Output Buffer Information Specification (IBIS) model is a standard in the semiconductor industry for modeling semiconductor devices from a behavioral perspective, for both analog and digital perspectives. IBIS modeling enables engineers to describe detailed signal behavior in a circuit design without revealing proprietary information about the circuits (or the processes used to make […]
Current feedback amplifiers, Part 2
Part 1 of this FAQ look at the operation of the CFB op amp and compared it to the VFB op amp. Part 2 continues the discussion of these two op amp topologies and their characteristics. Q: How do you choose between VFB versus CFB? A: Today’s CFB and VFB amplifiers have comparable performance, but […]