The piezoelectric effect. From principle to product.
Certain ceramics generate an electrical charge when pressed. That single physical principle is the foundation of every RNC switch, keypad, and panel. No moving parts. No mechanical contacts. No wear. Understanding how it works explains why piezo outlasts, outperforms, and outsurvives every conventional interface technology.
Press a surface. Get a signal.
When you press a surface with a piezoelectric ceramic disc behind it, the disc deforms by a few microns. That deformation generates an electrical charge. Release the pressure, the charge dissipates. That is the entire principle. Mechanical force in, electrical signal out. Direct. Immediate. No intermediate mechanism.
The signal the disc generates is a brief voltage pulse. Its amplitude depends on the force applied and the properties of the ceramic material. Converting this raw pulse into a reliable, repeatable switching output requires electronics that condition, filter, and interpret the signal. This is where the engineering begins.
How a ceramic disc becomes a sealed switch.
A raw piezo disc generates a signal but it is not a product. Turning the piezoelectric effect into a reliable, sealed, production-ready switch requires mechanical engineering, electronics, and signal processing working as one system.
The disc must be mechanically coupled to the activation surface so finger pressure transfers efficiently to the ceramic. How this coupling is engineered determines the sensitivity, consistency, and long-term reliability of the switch. The electrical connection from the disc to the signal electronics must survive millions of thermal cycles and years of vibration without degradation.
In an RNC switch, the housing is machined from a single piece of stainless steel or aluminium. The piezo element and electronics are fully potted inside with an application-specific compound that fills every cavity. No air gaps, no voids. The potting protects the electronics, locks the piezo element in position, provides vibration damping, and creates an additional seal barrier.
The result is a monolithic unit with no moving parts, no gaskets, no seams, and no ingress path. IP69K is not achieved by adding better seals. It is inherent in the one-piece construction. The product is sealed after manufacture. You cannot inspect, adjust, or repair the inside. It must be right the first time, every time.
How RNC approaches build quality →What changes when you remove the moving parts.
Every conventional switch relies on mechanical movement to function. Remove that movement and you eliminate the entire failure category that comes with it.
How piezo compares to other interface technologies.
We have published a detailed engineering comparison of piezo against mechanical, membrane, capacitive, and inductive switching. It covers durability, environmental performance, usability, power consumption, and design flexibility.
| Piezo | Mechanical | Membrane | Capacitive | |
|---|---|---|---|---|
| Moving parts | No | Yes | Yes (dome) | No |
| Sealed without gaskets | Yes | No | No | Partially |
| Works with any glove | Yes | Yes | Yes | No |
| Senses through metal | Yes | No | No | No |
| Typical lifecycle | 50M+ | 1-5M | 1-5M | Unlimited* |
| IP69K inherent | Yes | No | No | Possible |
The piezoelectric effect is well understood. What we build on top of it is a leap beyond.
The piezoelectric effect is open physics. Dozens of companies make piezo switches based on the same principle, the same ceramic, the same basic construction. What separates a commodity piezo switch from an RNC PiezoTouch product is everything that happens after the disc generates its signal.