Light has varying definitions; it’s usually limited to the visible portion of the electromagnetic spectrum, but sometimes it’s defined to include the near-infrared (IR) and ultraviolet (UV) portions. For example, LidAR (light detection and ranging) uses various portions of UV, visible, or near IR spectrum to image objects. And ‘light’ has a different definition if […]
Quantifying embedded MCU energy consumption
There are several methods and benchmarks for quantifying the energy consumption of embedded microcontroller units (MCUs) and related energy consumption benchmarks for common peripheral functions such as Bluetooth low energy and Wi-Fi. Over time, MCU designs have changed to support the demand for higher energy efficiency. In addition, there is another world of energy consumption […]
Specifying MCUs for satellites and spacecraft
There is not a single group of standards but a continuum of qualification criteria for the components and systems used in satellites and spacecraft (Figure 1). With the growth of low earth orbit (LEO) satellites where the environment is less demanding and where some satellites are expected to be replaced regularly with upgraded designs, the […]
How does embedded software work?
Embedded software is specialized programming on a chip, such as a microcontroller (MCU), or in firmware in an embedded MCU, to control its functions. Unlike general computer applications, designed to be installed on various computer systems or modified to provide varying levels of functionality, embedded software is generally purpose-built for a single hardware environment and […]
What’s special about embedded microcontrollers?
Embedded MCUs are purpose-built for use in various specific applications and rely on embedded peripherals, various communications protocols, conventional operating systems (OS) or specialized real-time operating systems (RTOS), middleware, application software, and development environments. While MCU stands for microcontroller unit, it could also be interpreted as mission controller unit since these devices are optimized for […]
What are voltage rail splitters and virtual grounds for batteries and PFCs?
Rail splitters are usually associated with battery-powered devices, but that’s not always the case. There are several definitions of a “rail splitter,” sometimes referred to as a “virtual ground” or “pseudo ground.” The most common meaning is creating a new “0V” reference point, usually the mid-point Vin/2 of a single supply voltage such as a […]
Power supply regulations, requirements, and standards
Regulatory standards cover safety and electromagnetic compatibility (EMC), in addition to efficiency. Safety and EMC standards are relatively straightforward, and their numbers are limited. Efficiency is a different matter: Society’s drive to reduce greenhouse gas emissions results in increasingly sophisticated energy efficiency standards for all types of power converters. It started with relatively simple ENERGY […]
Power supply control techniques
Power supply control has evolved from primitive ferroresonant regulation and linear power supplies to simple hysteretic control, analog voltage-mode control, analog current-mode control, and now various approaches to digital control. Compared with switched-mode power supplies, the output of ferroresonant designs is not as precisely regulated, while linear regulation can produce very tightly regulated and very […]
Two- and four-switch power conversion topologies
Compared with one-switch topologies, two- and four-switch power conversion topologies have several benefits in addition to the ability to process higher power levels. This FAQ will review some of the basic two-, and four-switch topologies. It will look at where they are used and their performance tradeoffs. This article does not consider various switched capacitor […]
What is one-switch power conversion?
DC/DC conversion is the basic building block for many power converter designs including AC/DC power supplies, battery chargers, and uninterruptible power systems. This FAQ reviews some of the most common one-switch topologies. Specialty topologies such as the Joule Thief are not included. This article also does not consider various switched capacitor topologies, a review of […]
