Piezoelectric

35mm Piezoelectric Sensor (Vibration & Impact)
This sensor operates on the Piezoelectric Effect. When you tap, bend, or vibrate the disc, the ceramic material experiences mechanical stress, which causes an internal shift in electrical charges. This results in a voltage spike across the two wires. The harder the impact, the higher the voltage produced.

 
Why the 35mm Disc is a Project Essential:
• Self-Generating (Passive): It requires zero power to "listen" for vibrations. This makes it incredible for low-power or battery-operated projects that need to "wake up" only when an impact is detected.
• Dual-Purpose (Sensing & Sound): While it is an excellent vibration sensor, it can also act as a buzzer. If you apply an oscillating electrical signal to it, the disc will vibrate and create sound.
• Ultra-Thin Profile: At less than 1mm thick, it can be hidden under surfaces, taped inside a drum, or even placed inside the sole of a shoe to track footsteps.
• Extreme Sensitivity: 35mm is a relatively large diameter for a piezo disc, which increases its surface area and makes it highly sensitive to even subtle vibrations or distant knocks.

 
Technical Capabilities:
• Voltage Output: A sharp knock can produce a spike of over 10V to 50V. While the voltage is high, the current is extremely low.
• Fast Response: It reacts in microseconds, making it ideal for detecting high-speed events like a ball hitting a target or a glass breaking.
• Durability: With no moving parts to wear out, these sensors can withstand millions of taps and vibrations.

 
Best For:
The 35mm piezo is the gold standard for knock-activated locks, electronic drum pads, security alarms (glass break detectors), and energy harvesting experiments (turning footsteps into milliwatts of power).