Hall effect sensors are everywhere right now. Keyboards, game controllers, and DIY kits use them to make more precise inputs. But with any newly popular device, it can be easy to immediately jump to the hype and assume that a new technology is better without knowing the advantages.
As a fan of mechanical keyboards who has also reviewed peripherals that employ Hall effect sensors, I’m excited about the technology. I’m here to help answer all your questions, whether you’re deciding to upgrade or just want to know what the Hall effect means.
What is the Hall effect?
The Hall effect is a principle of magnetic fields. discovered by Edwin Hall in 1879. He discovered that placing a magnet next to an electric current flowing through a conductor would cause the electrons to move with the position of the magnet. This affects the voltage of the current when the electrons are pushed to both sides of the conductor. The resulting changes in voltage can be measured to determine the distance from the magnet to the conductor.
Put more simply, bringing a magnet close to an electrified piece of metal will cause electric current to react, and this reaction can be measured. A Hall Effect (HE) sensor measures this voltage change and returns a value to the computer.
This principle is used today in countless technologies in multiple fields. One of the most common uses is as a car wheel speed sensor. These sensors use the Hall effect to measure the speed at which a wheel rotates, which is then reported to the car to control things like cruise control, ABS and the speedometer.
Hall effect sensors have also been used in computer technology for decades. Honeywell produced the first Hall-effect keyboards in the 1970s and 1980s, but the technology eventually fell out of favor as more cost-effective keyboards became widespread. It only started to re-emerge in the 2010s with manufacturers like XMIT producing small batches of modern HE keyboards.
Advantages of the Hall effect in peripherals
The biggest improvement that Hall effect sensors offer is response time. Because an HE switch relies on magnets rather than physical contact to register input, it can theoretically register information much faster than a traditional mechanical keyboard switch. This is one of the main reasons HE switches are popular in esports and competitive gaming, where milliseconds matter.
For the average keyboard enthusiast, the most impressive feature of an HE switch is how the sensor registers user input. A traditional mechanical switch will only return two binary values of “on” and “off” in static positions. It will tell your computer when a switch is pressed beyond a certain point, but it doesn’t provide any other information. On the other hand, a Hall effect switch can return a multitude of numbers that correlate to the position of the switch. These values range from near the top of the switch, to halfway down the keystroke, to fully compressing the switch. As a result, the computer will know exactly how far the key is pressed and will be able to provide variable input based on this information.