Your Electronics Open Source

Striking Gold in Advanced Analogue From Farnell
Today’s world is heavily reliant upon monitoring and control of a wide variety of physical effects, for example to utilise resources such as energy more efficiently, and to realise improvements in quality of life. Examples of electronic products that are used to achieve these goals include fuel metering and exhaust monitoring systems, medical scanners, portable health monitoring instruments, remote equipment-status monitors, and advanced security systems. Although the complex processing algorithms that make much of this possible are typically accomplished most quickly and economically within the digital domain, the natural world does not follow the digital roadmap defined by Moore’s Law, and with the human desire for faster and cheaper; it remains resolutely analogue in nature. Hence, engineers must continue to address the challenges in accurately sensing signals in the analogue world and delivering these faithfully to a point where they can be converted into the digital domain.

Analogue alchemy
Analogue design has long been recognised as a black-art, demanding considerable knowledge as well as intuition to ensure the stability of the system, optimise gain and frequency response, deal with grounding issues, manage impedances and matching, and mitigate the effects of noise. At the same time, pressure is growing to meet stringent cost, time to market and high-volume-manufacturability targets. Modern engineers, for the most part, simply do not have the luxury of being able to individually optimise analogue circuits. To address these issues, the most arcane analogue alchemy now tends to happen at the silicon level; the design gold is embedded within the components that make up the signal chain. The latest analogue products nfrom leading manufacturers now seek to “pre-solve” many of the challenges that used to occupy specialist analogue engineers. They are more feature-rich, as well as being less susceptible to variables such as PCB trace lengths and layout. They are also inherently less power-hungry than their predecessors. Hence the latest-generation products emerging from IC vendors are easier to design-in, require fewer external components, support system-level power-management schemes, and use the latest surface-mount package technologies to support high-speed, repeatable assembly.

Products from Farnell
By offering one of the broadest portfolios of signal chain technologies, from influential innovators of advanced and high-performance analogue products, Farnell is ideally positioned to help the designer identify, select and evaluate the products that are now available. To facilitate evaluation, selection and integration of signal chain products to meet ambitious system objectives, Farnell divides the core technologies into five key areas that are easily remembered as MIDAS: Mixed Signal, Interface, Data Conversion, Amplification, and Sensors.
The Mixed Signal category includes devices such as multiplexers, analogue switches, filters, digital potentiometers, isolators, resistors and trimmers. When considering Interface products, engineers have numerous connectivity options including SERDES, LVDS transceivers and Ethernet interfaces. This group also includes oscillators, PLLs and clock devices. Data conversion is the stage of the signal chain closest to the digital domain, comprising various classes of DACs and ADCs including general-purpose, high-speed and high-precision devices depending on the application and system specification. Among the Amplifiers category, engineers will be selecting from an extremely wide range of available options, again largely determined by the application and system performance requirements. Amplifiers available from Farnell’s industry-leading suppliers include audio, current-sensing, differential, general purpose, instrumentation, isolation, logarithmic, operational, programmable gain and video/buffer amplifiers, as well as a wide range of comparators, and companders. Finally, by considering suitable sensors, including accelerometers, current, Hall Effect, pressure, proximity and temperature sensors, alongside the other four categories, engineers can complete their analysis of the signal chain requirements for any number of monitoring, logging or control systems. These may span applications ranging from medical or automotive, to industrial, commercial and domestic systems.
By analysing the signal chain in this way, engineers can quickly identify the elements required to complete a solution, and begin assembling an optimal combination.

Latest technology, available first
In this Technology First campaign, we review some of the latest developments and trends in each of the five categories, to identify how component performance and features are easing analogue design challenges, cost-effectively improving performance, and supporting reduced physical size and power consumption. Finally, it is important to note that Farnell is also able to supply complementary components, to satisfy the digital-design requirements and achieve a comprehensive, high-performance system implementation.
Farnell