Transistor-transistor logic (TTL) and complementary metal oxide semiconductor (CMOS) logic are the principal types of integrated circuit-based logic gates implemented in digital circuitry. TTL employs bipolar junction transistor technology while CMOS uses the field-effect transistor concept at the input. TTL consumes far more power than CMOS, which is one reason CMOS has eclipsed TTL as […]
FAQ
RISC-V: an Open Instruction Set Architecture
The benefits of open source have been bestowed upon an Instruction Set Architecture (ISA) called RISC-V. One of the earliest, best-known examples of open source technology is Linux. For a widely accepted, official definition of open source, see The Open Source Initiative. Open source does not stop at Linux, however. One of the more recent […]
Driving LED arrays, Part 2: power
Part 1 of this FAQ looked at the basics of using LEDs in series, parallel, and series/parallel arrays, the implications on the power-sourcing requirements, and the impact of an LED failure. Part 2 looks at other practical issues associated with powering the array. Q: Given the various configurations, what sort of drive is “best” for […]
Rotary encoders, Part 2: magnetic encoders
Part 1 of this FAQ looked at the optical rotary encoder, a low-cost, high-resolution, easy-to-use sensor for indicating incremental shaft position (although it can be “upgraded” to indicate absolute position as well). Q: What is the basic principle of the magnetic encoder? A: The magnetic encoder uses a rotating gear made of ferrous metal and […]
Basics of measurement resolution
In electronic instrumentation, resolution is a measure of the distance in amplitude at which we can distinguish between two points on a waveform. This is not the same as accuracy, which is a measure of how closely a waveform as displayed or measured agrees with the signal at the instrument’s input. One of the principal […]
Can SSDs replace all storage and memory?
The short answer is no. Here’s why. Solid-State Drives (SSDs) have no mechanical or moving parts, which makes them ideal for mobile devices. SSDs are associated with flash memory and as a replacement for hard disk drive storage for computers. At the lowest level, SSDs are based on transistors (similar to DRAM), but SSD is […]
Rotary encoders, Part 1: optical encoders
Across a wide range of applications, it is necessary to need to accurately sense the motion of a rotary shaft and know its position, speed, or even acceleration. To do this, a component called a shaft or rotary encoder is added to the motor/shaft assembly. (Note that the term “rotary encoder” is often shortened to […]
Driving LED arrays, Part 1: topologies
Light-emitting diodes – often referred to simply as LEDs – have become the preferred light source in many applications, whether for area illumination, spotlighting, signage, or backlighting. While there are some applications which prefer to use a smaller number of very high-power LEDs, many applications benefit from, or must use, a larger number of lower-to-moderate-power […]
Making measurements on balanced transmission lines
Stray electrical fields are everywhere. They infiltrate signal transmitting and receiving devices as well as the transmission lines that connect them, taking the form of noise and unwanted signals. The effect is to raise the signal to noise ratio, obscuring desired analog and digital information. There are mitigation techniques, but to be effective they must […]
VIDEO: Domains in the Tektronix MDO3000 Oscilloscope
An overview of time and frequency domains and demonstration of the Spectrogram. Hi again and welcome to our 85th Test and Measurement Video. Today we’ll talk about domains in the Tektronix MDO3000 oscilloscope. By way of background, in mathematics a function is frequently graphed in Cartesian coordinates. Two axes intersect at right angles at the […]
