Vibration Sensor

The piezo sensor is usually used for flex, touch, vibration and shock measurements. A small AC and large voltage is created when the film is touched or moved.

Step 1: What You'll Need

Breadboard

Jumper wires

Piezo film vibration sensor => http://uk.rs-online.com/web/p/vibration-sensors/89...

Dual Op Amp (LM358) => http://uk.rs-online.com/web/p/operational-amplifie...

Zener Diode (5.1v)

Capacitor: 100nF

LED

Resistors: R1: 1MΩ

. R2: 100KΩ

R3: 1KΩ

Rf: 200KΩ

Rpot: 100KΩ (potentiometer)

RL: 220Ω

Step 2:

The purpose of the Zener Diode is to protect the IC from large voltage spikes

The capacitor serves as a DC decoupler

The Variable resistor (potentiometer) adjust the threshold

Step 3:

The LM358 is a dual Op Amp, we'll be using it as a non-inverting amplifier and a comparator

The gain(A) of the amplifier can be changed to suit your need. All you have to do is change the values of R3 and Rf.

A = 1+(Rf/R)

In this circuit, the gain is 201 therefore: 201=1+(Rf/R) {choose a value for R and the find Rf or vice-versa }

Step 4: Circuit Diagram