Asynchronous drive from Analog

Run smarter – Live longer!

Breathe smarter – Live longer!

Tick smarter – Live longer!

I could continue listing these slogans for designing better electronics for the era of trillions of devices and peta, exa and zetta bits of information produced on our small planet.

Ultimately it is about how good we are in TIMING our ingestion and processing of information. TIMING has been and will always be a key design factor which will determine other factors such as performance, accuracy, energy efficiency of the system and even productivity of design processes.

As computing spreads into periphery, i.e. it goes into ordinary objects and fills the forms of these objects like water fills the shape of the cup, it would be only natural to think that computing at the peri or edge should be more determined by the nature of the environment rather than rules of computer design dominated the by-going era of compute-centrism. Computing for ages has been quite selfish and tyranic. Its agenda has been set by scaling the size of semiconductor devices and growing complexity of digital part. This scaling process had two important features. One was increasing speed, power consumption which has led to an ongoing growth in data server capacity. The other feature was the only way to manage complexity of the digital circuitry was to use clock in design to avoid potential racing conditions in circuits. As computing reaches the peri it does not need to become as complex and clocky as those compute-centric digital mosters. Computing has to be much more environment friendly. It has to be amenable to the conditions and needs of the environment – otherwise it simply won’t survive!

But the TIMING factor will remain! What will then drive this factor? It won’t certainly only be the scaling of devices and drive for higher throughput by means of clock – why? for example, because we will not be able to provide enough power for that high throughput – there isn’t enough lithium on the planet to make so many batteries. Nor we have enough engineers or technicians to maintain replacing those batteries. But on other hand we don’t need clock to run the digital parts of those peri devices because they will not be that complex. So, where will TIMING come from? One of natural ways of timing these devices is to extract TIMING directly from the environment, and to be precise from the ENERGY flows in the environment.

We have always used a power supply wire in our electronic circuits. Yes, but we have always used it as an always-ON servant, who had to be there to give us 5 Volts or 3 Volts, or more recently 1 Volt or even less (the so-called sub-threshold operation) like 0.4 Volts. That wire or signal has never been much of a signal carrying information value. Why? Well because such information value was always in other signals which would give us either data bits or clock ticks. Today is time to reconsider this traditional thinking and widen our horizon by looking at the power supply signal as a useful information source. Asynchronous or self-timed circuits are fundamentally much more cognizant of the energy flow. Such circuits naturally tune their tick boxes to the power levels and run/breath/tick smarter!

At Newcastle we have been placing asynchronous circuits at the edge with the environment into analog electronics. In particular, it has been power regulation circuits, A-to-D converters and various sensors (voltage, capacitance, …). This way allows significantly reduce the latencies and response times to important events in the analog, reduce sizes of passives (caps and inductors), but perhaps most importantly, thanks to our asynchronous design tools under Workcraft (http://workcraft.org) we have made asynchronous design much more productive. Industrial engineers in the analog domain are falling in love with our tools.

More information can be found here:

http://async.org.uk

https://www.ncl.ac.uk/engineering/research/eee/microsystems/

 

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