ANALOGUE DESIGN DSPs DSPs are critical to how our electronics communicate with one another, but what does the future hold for this technology? By Aneet Chopra DSPs AND MODERN DEVICE DESIGN ith almost any technology, the path to progress is chaotic. No matter how mundane the gadget in your hand might seem, it’s part of a market that is constantly iterating on itself. Designers are always reimagining, refining, and reinventing their products and, as a result, the devices we’re developing are having to accommodate an increasingly wide spectrum of inputs and signals. As new ideas take hold and our electronics become more capable of communicating both with us and with one another, we need them to be able to recognise and understand one another without missing a beat. This is especially important in the era of the Internet of Things (IoT). If we’re developing products capable of intelligently processing data and performing tasks autonomously, they need to be able to recognise stimulus perfectly and respond to it appropriately. Amidst the chaos of development, we also need to be able to rely on a common frame of reference for understanding those signals – technologies in common that help us to perform the basics of communication. W THE 101 ON DSP One of these is digital signal processing, or DSP. DSP silicon has been very popular and pervasive in all our devices; we use it on a day-to-day basis without even realising it. Just as it sounds, DSP is literally digitising the functions of analogue signal filters. You take real-world input and manipulate the maths behind that data in certain ways to achieve the desired output. Analogue filters are well established – but so are their limitations. A physical filter is fixed once you build it, which means that components themselves can delay, and their values can drift. The longer you use one, the more the quality of its output gradually deteriorates. DSP offers several advantages – the most obvious of which is that it’s not going to deteriorate in the same way. Encoding the filter digitally gives you a robustness that a physical alternative can’t necessarily match. Furthermore, DSP can incorporate very specific effects that are more difficult through analogue equivalents. That’s not just ‘cleaning’ the audio to better isolate and understand the signal within, but also augmenting it: compression, AUTHOR DETAILS Aneet Chopra , EVP Marketing & Product Management, XMOS modulation, equalisation, and so on. Once the process is complete, the device can output that signal however it’s intended. The ubiquity of DSP, then, comes from its consistency and its efficiency: it’s a trusted means of being able to receive and process key information. So, what does that consistency mean for modern device design? Why is DSP so important to the ways in which our electronics communicate with one another? Well, the electronics market has massively diversified over the past few years. It’s not so long ago that semiconductor manufacturers could sink an immense amount of time and resource into chips for one specific market sector: personal computers, digital cameras, and so on. These days, as more and more smart devices have been brought to the table and entirely new markets have sprung up, we’ve seen a diverse market of small niches emerge, each with unique requirements. In an ideal world, every company designing a product has the money, time, and supply to cater to that niche with the perfect hardware. But with the sheer number of use cases and applications, that’s not realistic. 44 / MAY 2024
New Electronics May 2024: Page 44
