Many who develop with microcontrollers have access to compatible Wi-Fi modules. Do you need to be concerned about updating to the latest version 802.11ax when it comes out? The answer depends on whether your MCU will reside in an area where the Wi-Fi access point is typically congested. If so, 802.11ax can help. In short, […]
FAQ
RF/Microwave noise, Part 2: Noise temperature and applications
Part 1 of this FAQ looked at the basic specifications of noise factor and noise figure, widely used in RF/microwave system and circuit analysis to predict and assess both requirements and performance. This part looks at the additional parameter of noise temperature, as well as the impact this parameter has on system performance. It also […]
IoT via Cellular: Out with 2G and 3G, in with LPWA
Wireless connections are convenient and cheap to set up, but Wi-Fi, Bluetooth, and other commercially available technologies do not always have the range needed. Wireless cellular is an option, but cellular connections are expensive. A lot of devices use 2G and 3G cellular technologies because they cost less, especially when only little chunks of data […]
RF/microwave noise, Part 1: Noise figure basics
The lower-frequency world of electronic circuits and systems for communications links routinely uses parameters such as voltage and current, bit rates, and signal/noise ratio, to cite just a few of many, many possibilities. While these are also important in the world of RF and microwave links and system functions, engineers doing work in this arena […]
Load switches, Part 1: Basic role and principle
Load switches are used to enable/disable power to selected ICs or circuit subsections. Although they don’t get much attention, they are useful for both saving power as well as management of multiple power rails. This FAQ will discuss their function, basic design, advanced IC implementations, and additional benefits of IC load switches. Q: What is […]
Making measurements with Matlab
Matlab was released in 1984 by Mathworks, an American privately-held corporation whose other major product is the closely-related Simulink. Additionally, Mathworks offers close to 100 other programs, such as Polyspace, SimEvents and Stateflow. Matlab’s main focus is numerical computing, including matrix and algorithm operations, plotting of data and functions and creation of user interfaces. It […]
Can you operate circuits at sub-threshold voltages?
Yes, you can operate circuits below the 0.9 volts where some transistors can run. The result is mind-blowingly low power consumption, as in a full-featured Real Time Clock (RTC) with a supply current below 14 nA (that’s nanoamps). First, some background on how transistors work Transistors operate much like an electronic switch. Apply voltage above […]
Load pull for RF devices, Part 2: How and where
Part 1 of this FAQ explained the what and why of load-pull tests of RF devices and impedance matching. Part 2 looks at various ways the test can be set up and run. Q: What’s the basic test setup for a modern load pull? A: As shown in the figure of Part 1 (and repeated […]
When tin whiskers spontaneously erupt
First reported in the 1940s, Metal Whiskers (MW) are spider-web-thin conductive filaments that sprout (most often) from tin, zinc, and cadmium metal surfaces. A “tin whisker” can be manually formed with poor soldering techniques, but metal whiskers actually grow on their own, too. They are a phenomenon that many engineers are not aware of. Silver, […]
What are hermetic connectors?
Hermetic connectors are designed to prevent ingress of air, gases and other liquids into the vacuum-sealed connector in extremely harsh environments. In testing, these connectors should show no detectable gas or fluid leakage. They should be able to withstand high pressures of 10,000 psi or more, ensuring a stable pressure differential on both sides of […]