Don’t ignore analog—it’s the secret sauce of IoT

Most of the innovation in IoT is focused on digital technology. From power servers running software in the cloud, to increasingly more intelligent devices operating ever closer to the edge in our factories, homes and personal devices. What is often lost in the discussion is that the very edge of IoT is still actually entirely analog, seen and measured in terms of light, pressure, temperature, proximity and so on.

In other words, IoT is really the intelligent manipulation of digital data generated from analog sources. Because analog technology sits at the very edge of the network, the quality of the analog layer ultimately determines the quality of everything else in the system, from the digital data generated to the insights drawn and the actions taken.

So, a noisy analog front-end will result in distorted digital information, which has major impacts on the entire system. Get the analog part right and the digital application will be all the better. What’s more, for IoT applications that control processes, digital information must also be accurately converted back into analog, at the edge.

Still don’t believe it? Here’s why analog is the secret sauce of the Internet of Things.

Analog parts + digital connectivity = effective IoT deployments

It may be unfashionable, or even unwelcome, but the truth is that many of the sophisticated devices that are essential to the IoT rely on analog technology. In fact, it is integral to the successful implementation and operation of the IoT. IoT applications simply won’t work without tried and tested solutions such as analog to digital converters (ADCs), digital to analog converters (DACs), voltage amplifiers and filters.

Sensors, for example, are fundamental in the IoT. IoT systems are made up of sensors and devices that connect to communicate and share data with each other either directly or via the cloud. Without them, there’s no way to gather and share data. Yes, some IoT devices integrate directly with digital sensors, but native analog often can be a far more accurate representation of the source of data. While ADCs integrated into a device can both lower development effort and cost as well as reduce the amount of power required to drive a device, discrete converters are still critical.

That data is then used to perform some kind of action, which may involve machines, electronic devices, human beings or some combination of those. Typical signal acquisition sources include temperature variations, light levels and pressure differences, as well as proximity, speed and touch-sensing. Others include the presence or absence of smoke, gases, CO2 and many more.

Defining the analog-digital gap

The fact is that most engineers involved in designing IoT-related solutions may primarily think digital and consider analog functions later in the design process, but this can create unnecessary obstacles while increasing a product’s time to market. IoT engineers need to bridge the gap between digital and analog design requirements earlier so that they can reduce product complexity while shortening development times. To help achieve this, they would benefit from greater awareness of and access to analog-based solutions that are created with digital designers in mind. These high-performance devices should be capable of handling a variety of IoT-based design challenges.

For example, power management circuits need switching regulators, pulse-width modulation controllers, power modules and drivers, and battery chargers. This can be addressed with linear products that includes comparators and amplifiers (such as current sense amplifiers, instrumentation amplifiers and op amps), as well as mixed signal products comprising analog/digital converters, power monitoring and metering ICs, current/DC power measurement ICs and digital potentiometers.

Defining the challenge and identifying the solution

Even with access to such capable products, many IoT engineers continue to see analog as an especially challenging prospect. For instance, it’s hard to keep up with the interplay of analog concepts such as feedback as well as amplification and filtering (to keep signals clean) when also negotiating these connections into complex IoT systems. When comparing filters, for example, the common perception is that an analog filter can involve far more complicated design than the low complexity of a digital option. Likewise, when looking for the best op amp, designers have to take into consideration whether the amplifier degrades the performance of the ADC or DAC. They also need to factor in signal range, gain, static and dynamic loading and power supply voltage.at times even more difficult than digital technology. This is a serious hurdle to IoT implementation because working at the edge requires good analog technology.

Another common misperception is that there is a trade-off: while analog circuits can be more difficult to design than digital circuits, the latter are likely to be a lot more costly. This belief that analog design is significantly harder can be self-defeating, because designers with a working knowledge of analog can be even more productive when working on the digital part of their applications. 

As a starting point, IoT engineers need to understand that analog design employs passive components along with diodes, transistors, op amps and other semiconductor devices to change the amplitude, frequency, or shape of an input voltage or current. The engineering challenge is to control signal fidelity, amplification and filtering prior to digitization, so it is essential that a designer be able to grasp the fundamentals of amplifiers, be they differential amplifiers, op amps or others. Think of amplifiers in terms of smart homes; strong analog technology makes the audio technology for voice assistants or notifications much easier. [WJ1] While designers may understand and appreciate the importance of analog, there is still an analog/digital divide that needs to be overcome

End-to-end partners are a bridge from analog to digital and beyond

Navigating that technical complexity is part of what a strong end-to-end partner can offer to designers. Genuinely created with digital designers in mind, industry leaders like Microchip offer a strong portfolio suited for any level of complexity. Plus, Avnet’s evaluation, development and reference boards, online design support centers, webinars, instructional videos and worldwide technical support link designers into a product development ecosystem to help get their designs to market.

Ready to go from thinking analog to designing analog? Then view our guide on the most critical areas of analog for designing in the IoT.