Magnets Might Be the Future of Switches…

Since the expiration of Cherry’s patent on the MX switch design in 2014, the world of mechanical keyboards custom and prebuilt alike have largely been overtaken by the MX footprint. While there are still some holdouts of Alps and Topre enthusiasts out there trying to fight against the current, it’s hard to deny that there’s any competing with the two part leaf and cross-shaped keycap mounting point that has become emblematic of the hobby as it is today. However, this wasn’t always the case. Long before Cherry’s patent lapsed and the rubber dome technology ran rampant through OEM keyboard designs, companies used to design the switches used in their keyboards from the ground up. It’s because of the inventiveness required to do something as complex as this that there’s so many unique and cool looking vintage keyboards that can still be found out there today. On the flip side, though, the lack of coherent and consistent design themes between different companies over the years is exactly what has prevented a standard of ever being established over the years. Well, that much is at least partially true up to now. What if I told you that there was some very old switch technology starting to gain some traction again in today’s modern, highly competitive keyboard market? This article dives into “Hall Effect” switches and why the future of switches might have a whole lot more magnets in it than you would have guessed…

First introduced all the way back in the early 1970’s by tech giant Honeywell, Hall Effect (HE) switches are ones which, in the broadest of senses, use a weird trick of physics that occurs between magnets and electricity in order to register a simple keypress. While the original Honeywell Hall Effect switches were certainly unique in their shape and general execution, the underlying technology was actually a lot more widespread back then than people realize, with “Hall Effect” or “Magnet Switches” appearing in several other brands of keyboards throughout the 70’s and 80’s such as RAFI and Nixdorf. Yes, you read that right – the same company responsible for the famous Cherry MX Nixdorf switches known as ‘Nixies’ also had boards with magnetic valve switches in them before the Nixies were ever produced! Falling a bit out of fashion in the 90’s and 00’s, HE switches are once again beginning to make a comeback, with prebuilt brands like Wooting and Akko reviving the ancient technology with a little bit of fancy PCB designing in order to help stand out from the heavily MX-favored prebuilt keyboard market. Even custom keyboard companies like Geonworks, Matrix Labs, and AEBoards are all beginning to jump on this trend too, making it spread even faster than even I had at first guessed. However, the fancy programming and extra design work being put in by all these companies isn’t just for show, as the Hall Effect switches don’t work anything like what you’re used to in traditional MX-style switches…

Figure 1: Honeywell 'Micro Switch' Hall Effect switches in a keyboard.

Since the day they were first released back in the 1980’s, the MX-style of switches have operated through the use of two metal leaves that were connected to the PCB directly and then separated or allowed to come together through the use of the stem in the switch. When the stem is pressed inwards, the metal leaves come together to touch, complete a circuit with the PCB, and register a keystroke. On the upstroke, the leaves are then separated, the circuit is broken, and the keyboard no longer registers an input. In the simplest of senses, MX-style switches work just like the basic light switches in most rooms and are fully on or fully off with no in between. Hall Effect switches, on the other hand, are “contactless” and have no metal that connects their internal structures with the PCB at all. Instead, HE switches work via an interaction between electromagnetic sensors in the PCB and magnets which are embedded inside of the stems of the switch. All the way back in 1879, Edwin Hall discovered that a current of electricity will have a force exerted on it if a magnet is moved perpendicular to it, causing the electrical current and magnetic fields to interface. Dubbed the ‘Hall Effect’, the PCBs used in HE switch keyboards operate on this principle and have tiny currents of electricity running underneath each switch that can feel the force of the magnets in the stems of the switches when you depress them and move it closer to the PCB. Unlike normal MX-style switches which can only ever be fully on or fully off, though, sensors hooked up to these currents can tell just how strong the force that the current feels is, with the stems being pushed all the way down producing a stronger force than those only pressed halfway down. Where the fancy programming used in HE switch keyboards comes in is that it allows the users to effectively choose how much force felt by the sensors counts as a “full” keystroke. Think about it kind of like a dimmer switch for a lightbulb rather than a simple ‘on or off’ mechanism – you can choose how much “on” you want the light to be with a huge spectrum of options! While it’s a bit more complex than that in reality, the difference between MX and HE switches is actually about that simple.

Figure 2: A much more picture-heavy representation of the Hall Effect in keyboard switches from Daniel Beardsmore.

Admittedly, its probably easy to think that all of the effort required to exploit physics and redesign keyboard PCBs for Hall Effect switches over MX ones isn’t much worth the effort that everyone seems to be putting in. However, there’s actually some benefits to be had in using Hall Effect style switches even in spite of their tradeoffs. If you can deal with the fact that there’s not too many boards that operate on this style of technology out there as of the time of writing this article, some people will argue that the smoothness of the switches alone makes them worth hunting down. Without any internal leaf mechanisms that have to touch the springs, linear HE switches almost always have less surface area for scratch to occur than linear MX-style switches. As well, the sheer ability to program the actuation point of the switches as ‘on’ at 25%, 35%, or even 85% of the way through a downstroke is a pretty big draw in functionality over that of traditional switches even if they are hard to come across. Do keep in mind, though, that if you hunt down a Hall Effect keyboard and switches separately that not all boards’ programming works equally as well across all brands of switches. Hall Effect switches aren’t quite as cross-compatible as MX-style ones… yet. Don’t worry too much about the accessibility of these, though, as the technology seen in modern Hall Effect switches seems to be being worked on by more and more companies by the day.

Figure 3: Underside of a Gateron Dual Rail Magnetic Orange switch showing the magnet embedded in the center of the stem.

As Hall Effect switches are making a resurgence and run on the MX-switch market, and potentially fighting Topre for bragging rights along the way, we certainly will be seeing more of these switches pop up in the coming years. At the time of writing this article, I know of over 50 different switches out there with dozens more on the horizons from well-known switch manufacturers like Kailh, Outemu, and most notably Grain Gold and Gateron. So if this switch technology or some of its particular benefits sound a bit interesting to you, consider hunting down a Hall Effect keyboard to be on the cutting edge of it all. Or if you’re okay in sticking with the traditional MX design, consider learning more about that in my articles here on Dangkeebs such as ‘A Short Talk About Long Stem Poles’ or ‘A Few Switch Lubing Tips’!