Engineers designing game controllers must consider both performance and touch responsiveness. Here’s an overview of what makes good gaming hardware and a profile of the latest touch switches for gaming environments from C&K.
An unresponsive controller can ruin a player’s experience and throw themselves into a room, but even a great controller has to endure a lot of abuse. C&K recently released a number of new touch switches that give us the opportunity to think about what demands come with this application.
Game controller design considerations
When designing a product, the environment it will be exposed to is a critical factor. High temperatures require high temperature parts, thermal cycling environments must consider expansion and cracking of the weld, etc.
A game controller is most often used in a good, temperature-stable environment with controlled humidity. However, game controllers are not ordinary hardware. They’ve smashed their keys hundreds of times in a single minute, aggressively flipping when a character navigates a scene, and flinging themselves through rooms when a player becomes frustrated.
The Sony PlayStation DualShock controller, considered by some to be the pinnacle of good controller design. Image used courtesy of Evan Amos.
Despite being used in stable conditions, the violent movements and extensive handling that come with the game create a harsh mechanical environment. The latest discussions may focus on virtual reality gameplay advancements and game graphics updates, but the manual interface is still key to the experience.
A decent game controller should use parts that can handle a high degree of mechanical force, as well as many mechanical cycles. A typical tactile switch cannot do in such situations.
The importance of a good switch
While some components in a circuit can be replaced by less expensive versions with little to no effect on overall performance, there are some parts of a bill of materials that cannot afford the sacrifice. Interfaces are a good example, as the feel of the buttons and the responsiveness of screens can be just as important as a device’s specifications.
The latest discussions may focus on virtual reality gameplay advancements and game graphics updates, but the manual interface is still key to the experience. Poorly done product reviews often focus on the feel of the toggle interfaces, describing them as too heavy, “sticky,” “having no touch at all,” or failing after multiple keystrokes. Conversely, designers continue to update the Switch push button to improve the user experience.
For an example of the inside of a game controller, check out our Steam controller teardown.
C&K Tactile Switches
To meet the demanding industry requirements for switches, C&K announced this week its latest line of miniature switches that are well suited for gaming environments. These switches, which can be mounted directly on the PCB, are customizable, allowing designers to fine-tune the exact feel and sound when pressed.
The KMT0 switch. Image used courtesy of C&K.
One of their ranges of switches is the KMT0 nano-miniature SMT top trigger which have the smallest footprint in the C&K line. These switches are rated for up to 1 million cycles, have a 50 mA contact current rating, a contact resistance of less than 150 mΩ, and operate between -40 ° C and 85 ° C. Their incredibly low profile and Ability to handle many mechanical cycles makes this switch also ideal for Bluetooth headsets and MP3 accessories.
The KXT3 switch. Image used courtesy of C&K.
Another switch is the KXT3 ultra-low profile top actuated tactile switch which measures just 3mm x 2mm and 0.6mm high. The switch is capable of up to 500,000 cycles with an operating temperature range of -40 ° C to 85 ° C. An alternative to the KXT3, the KSC2 and KSC4 are sealed tactile switches that have an IP rating of IP67, making them makes it incredibly resistant to the unstoppable spill of energy drink, as well as being useful for outdoor equipment and even virtual reality applications.
The KBD switch. Image used courtesy of C&K.
Controllers are not the only products used by gamers. The computer keyboard is also one of the most common mechanical input devices for games. While ghost protection and LED backlighting can be incredibly useful, the only feature gamers (and even engineers) look for in a keyboard is touch; There’s nothing like the feel of an old IBM clicky keyboard! The KBD series of C&K switches are touch keyboard switches with an electrical life of up to 50 million presses. These switches are rated for 10 mA at 12V, have a contact resistance of 200 mΩ, and operate at temperatures between -10 ° C and 70 ° C.
For what other applications are these design considerations important? What other touch switches have you used in the past? Let us know in the comments below.