Touch Plate Circuit With High Sensitivity PCB

This is a highly sensitive touch plate circuit utilizing the NE555 timer IC, which activates a buzzer when a person touches the metal plate or hovers their hand above it. Compared to previously published touch control switch circuits, this design offers enhanced sensitivity, capable of detecting input voltages as low as 1 microvolt. The circuit can be adapted for various applications, including touch plate lighting or motor control, with necessary modifications. The primary component of this circuit is the 555 IC, which triggers when pin number 2 receives a voltage of approximately 1 microvolt. A relay connected at the output enables the circuit to function as a switching mechanism. In this particular configuration, a Unijunction Transistor (UJT) is connected through an output transformer to produce sound.

The touch plate circuit employs the NE555 timer IC in monostable mode to achieve high sensitivity. The circuit is designed so that when a conductive object, such as a finger or hand, approaches the metal touch plate, it induces a small voltage change that is detected by the 555 timer. The sensitivity can be adjusted by varying the resistor and capacitor values connected to the timer, allowing for fine-tuning according to specific application requirements.

The output of the NE555 timer drives a relay, which can control a variety of loads, such as lights or motors, depending on the design requirements. The relay acts as a switch that closes when the timer is triggered, allowing current to flow to the connected load. This feature makes the circuit versatile for different applications.

In the sound-producing configuration, the UJT is utilized to generate a tone when the relay is activated. The UJT can be configured to oscillate, producing a square wave output that drives the output transformer. This transformer converts the low-voltage signal from the UJT into an audible sound through a connected buzzer or speaker.

Overall, this touch plate circuit is a practical solution for applications requiring sensitive touch detection, with the potential for integration into various electronic devices. The modular nature of the circuit allows for easy modifications to suit different operational needs, making it an effective choice for designers and engineers.Here is a high sensitive touch plate circuit using NE555 which turns on a buzzer when anyone touches the metal plate or by hovering his hand over the plate. From the previously published touch control switch circuit, this circuit has an advantage of high sensitivity that it can detect an input voltage as low as 1 micro volt.

This circuit is attac hable to various designs such as touch plate lightning or motor control with necessary alterations. As i said before, the main component of this circuit is a 555 IC which triggers when the pin no. 2 gets a voltage about 1 micro volt. The relay connected at the output will allow you to use this as a switching circuit. In this specific circuit, a UJT is connected through an output transformer to produce a sound. 🔗 External reference