Modern electronics should be able to easily solve a temperature-sensing challenge, but the harsh real-world complexities make it a difficult proposition. Part 1 of this article looked at the basic issues of railway bearing failure and detecting these before they happen. This part looks into more details and sensing options. Q: What can the railroad […]
FAQ on railroad hot-box-temperature sensing, part 1
Modern electronics should be able to easily solve a temperature-sensing challenge, but the harsh real-world complexities make it a difficult proposition. Freight railroads are a very important part of the logistics infrastructure around the world for transporting raw materials as well as finished goods. They are a major constituent of intermodal transportation along with trucks, […]
Smoke detectors and alarms, Part 4
The low-cost, reliable, ubiquitous smoke detector is an example of complex physics and optics made real by semiconductors. Technology is always improving and adding features to existing products, and that’s true of smoke detectors and alarms. At the same time, the “protection” world is very cautious about adding features and frills which may detract, impede, […]
Smoke detectors and alarms, Part 3
The low-cost, reliable, ubiquitous smoke detector is an example of complex physics and optics made real by semiconductors. Given the huge market for smoke alarms of both types – easily tens of millions of units per year for new and replacement/upgrade units – it’s no surprise that many IC vendors offer components and reference designs […]
Smoke detectors and alarms, Part 2
The low-cost, reliable, ubiquitous smoke detector is an example of complex physics and optics made real by semiconductors. This part looks at the two widely used approaches to smoke detection. Q: How do smoke detectors actually detect smoke? A: There are two basic and very different approaches, one based on photoelectric principles and the other […]
Smoke detectors and alarms, Part 1
The low-cost, reliable, ubiquitous smoke detector is an example of complex physics and optics made real by semiconductors. We’ve come to accept the basic residential smoke detector, which retails for just $15 to $30, as a standard home-safety accessory. Most building codes now require these in or near designated areas such as the kitchen, bedroom […]
Signal integrity can’t kill the breakout box
Just when you thought the trusty breakout box would fall victim to high-speed digital signals, it lives on
PIGAs can indeed fly – and are still the best, Part 3: History and future
The PIGA is the oldest accelerometer and widely used in rocketry and guidance, and still the best – but MEMS-based devices are getting closer. The previous parts looked at the principle and operation of the PIGA. This part looks briefly at its history and refinement and the MEMS-based versions of the PIGA being developed and […]
PIGAs can indeed fly – and are still the best, Part 1: Frame of reference
The PIGA is the oldest accelerometer, is widely used in rocketry and guidance, and is still the best – but MEMS-based devices are getting closer. When you see an inexpensive drone, a more sophisticated one, an unmanned aircraft, a standard piloted aircraft, guided or intercontinental ballistic missile ICBM), an underwater drone or submarine, or a […]
Getting one wire to do more, Part 4 – headphone wire as antenna
Using one wire in two very different roles is widely done, requiring some simple circuity and basic components. Using a headphone wire as an FM antenna The earliest portable AM/FM portable radios used two antennas: an internal long wire wound on a ferrite core for the lower-frequency AM band (550-1600 kHz), and a “whip” antenna […]
Getting one wire to do more, Part 3 – Powering the antenna LNA
Using one wire in two very different roles is widely done, requiring some simple circuity and basic components. Providing DC power to an antenna amplifier via an RF coaxial cable In most applications where the antenna is located at a distance from the radio receiver front end, it is desirable or necessary to add a […]
Simple double-duty: How to get one wire to do more, Part 1: The rationale
Using one wire in two very different roles is widely done, requiring some simple circuity and basic components. It makes a lot of sense to use an individual single copper cable and its connection between two points to do more than it initially intended, especially if that additional function is aligned with the primary function […]
What are the varieties of electromechanical on/off switches?
Despite wide use of “soft” on/off switching, the traditional electromechanical switch is still often required or preferred and is available in countless versions. Let’s look at some available switch styles. 1) The knife switch It doesn’t get simpler than the knife switch. The first and simplest switch is the knife switch (Figure 1). This style […]
What are the parameters of electromechanical of/off switches?
Despite wide use of “soft” on/off switching, the traditional electromechanical switch is still often required or preferred and is available in countless versions. As with all components, there are some top-tier parameters as well as many secondary ones, and some of those secondary ones may be very important in a specific application. As expected, the […]
What are the symbols for electromechanical on/off switches?
Despite wide use of “soft” on/off switching, the traditional electromechanical switch is still often required or preferred and is available in countless versions. Switches are represented by their schematic diagram symbols, which correspond to the number and arrangement of their contacts. Schematic symbols tell part of the story In an electromechanical hardwired on/off switch, the […]
What is the role of electromechanical on/off switches?
Despite wide use of “soft” on/off switching, the traditional electromechanical switch is still often required or preferred and is available in countless versions. Switches are an integral, very necessary part of most electronic products. They have two broad roles: As power switches which, as their name indicates, cut the flow of power from the source, […]
The automotive Tire-Pressure Monitoring System, Part 4: Issues
Sensor-based monitoring systems for tire pressure can warn of potential problems, but there’s much more to the story than just a pressure-measurement system. The TPMS adds a highly specific safety-related feature to cars. However, as with many presumably good ideas, the “devil is in the details”, and that’s especially true for the TPMS. There are […]
The automotive Tire Pressure Monitoring System, Part 3: Implementation
Sensor-based monitoring systems for tire pressure can warn of potential problems, but there’s much more to the story than just a pressure-measurement system. Once the decision was made to use the direct measurement technique, IC vendors developed the needed components and equally important packaging. A TMPS requires a significant amount of analog, digital, and RF […]
The automotive Tire Pressure Monitoring System, Part 2: Perspectives
Sensor-based monitoring systems for tire pressure can warn of potential problems, but there’s much more to the story than just a pressure-measurement system. During the comments phase before the formal safety mandate was published per the legislative direction, the automotive-related communities had differing views on the need or wisdom of the electronic TPMS: The auto […]
The automotive tire-pressure monitoring system, Part 1: The situation
Sensor-based monitoring systems for tire pressure can warn of potential problems, but there’s much more to the story than just a pressure-measurement system. You may have had the misfortune to have the “Check Engine” light come on in your car. This single illuminated indicator encompasses a wide range of possible problems ranging from trivial where […]
The challenge of temperature measurement and sensor calibration, Part 3
Temperature is a widely measured real-world physical variable, but achieving credible results is harder than it seems, even for a simple device such as a kitchen oven. While many temperature-related measurements require high accuracy, precision, and repeatability – let’s say, to better than 1⁰C – many others do not, yet still bring challenges. Consider the […]
The challenge of temperature measurement and sensor calibration, Part 2
Temperature is a widely measured real-world physical variable, but achieving credible results is harder than it seems, even for a simple device such as a kitchen oven. What is temperature, anyway? While we all “know” intuitively what temperature is, actually defining and calibrating its readings is a complicated discussion. A fundamentalist approach is to go […]
The challenge of temperature measurement and sensor calibration, Part 1
Temperature is a widely measured real-world physical variable, but achieving credible results is harder than it seems, even for a simple device such as a kitchen oven. Calibration of a sensor and its associated electronics channel before making critical measurements or monitoring system performance is a common requirement in many situations. In some cases, it’s […]
Graphene-based flowmeter sensor measures nano-rate fluid flows, Part 3: The sensor
The first part of this article looked at the challenges of sensing nano-level flow rates such as found in the blood vessels. In contrast, the second part looked at graphene, an allotrope of elemental carbon at the heart of a new sensor used to measure those flows. This third and final part looks at the […]
Graphene-based flowmeter sensor measures nano-rate fluid flows, Part 2: The graphene context
The previous part of this article looked at the challenges of nanoflow sensors, especially with respect to blood flow. This part looks at graphene, which is the basis for the new sensor. Graphene is a material structure which did not exist until relatively recently. However, its constituent element of graphite – the crystalline form of […]