In this tutorial, we are making a project of an ultra-sensitive vibration sensor using a 555 timer and CA3140 IC. The purpose of this circuit is to sense any kind of vibration and switch on the relay so that you can operate any AC/DC appliance with this circuit.
The CA3140 is a BiMOS operational amplifier IC that has combined qualities of PMOS transistors i.e., MOSFET and Bipolar transistors. It is working as a comparator in this circuit. The other IC used in this circuit is a 555 timer IC. It is the most commonly used and versatile IC, the purpose of this IC is to provide time delays, oscillations, or pulses in the circuit. Another important component of this circuit is a PZT sensor, it is a piezoelectric sensor that produces a small amount of current when receiving any vibration.
Hardware Components
The following components are required to make an Ultra-Sensitive Sensor Circuit
| S.no | Component | Value | Qty |
|---|---|---|---|
| 1. | IC | NE555 Timer | 1 |
| 2. | IC | CA3140 | 1 |
| 3. | Sensor | PZT | 1 |
| 4. | Relay | – | 1 |
| 5. | LED | – | 1 |
| 6. | Diode | 1N4007 | 1 |
| 7. | Resistor | 1KΩ, 10MΩ, 1MΩ, 10KΩ, 470Ω | 1, 6, 2, 1, 1 |
| 8. | Electrolytic Capacitor | 220µF | 1 |
| 9. | Ceramic Capacitor | 0.1µF | 1 |
| 10. | DC Supply | 9-12V | 1 |
CA3140 Pinout
For a detailed description of pinout, dimension features, and specifications download the datasheet of CA3140
NE555 IC Pinout
For a detailed description of pinout, dimension features, and specifications download the datasheet of 555 Timer
Ultra-Sensitive Sensor Circuit
Working Explanation
The operating voltage of this circuit is 9 to 12 volts DC. When the piezo electric sensor will senses vibrations it will generate a current and send it to the CA3140 IC which will activate the transistor 2N3904. The transistor is acting as a switch here for the delay circuit. The delay circuit is built around 555 timer IC. So the 555 IC will activate now and switch on the LED and the relay for a specific period of this. The delay of this circuit depends on the capacitor Cx used with the 555 timer IC. The sensor’s sensitivity depends on the 10M variable resistor, it can be increased or decreased by increasing or decreasing the number of these variable resistors.
Applications and uses
- Vibration sensor
- Knock sensor etc.
