Free electronic circuit design and schematic diagram
A schematic diagram of a touch switch circuit is shown below. This circuit consist of timer, one shoot multivibrator and touch terminal. As timer, this circuit uses 555 timer which is connected to one-shot multivibrator. The touch terminal is used to trigger this circuit. The output of this circuit can be used to drive a power transistor, CMOS circuitry, hexFET […]
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This is an interface circuit for digital data input. This circuit consist of touch button, op-amp, diode, capacitor and resistors. Any conductor surface can be used as the touch probe, such as a machine-screw head having comparable area around 0.5-inch-square or similar area of any pattern on printed-circuit board. This circuit need a DC power supply that is produced by […]
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This schematic diagram is about touch switch circuit. Separate ON and OFF switch improves the ergonomics for safety, since the touching off button when the state is off doesn’t make the system acts in the opposite way: turning ON the system. This accident usually happens when we make wrong assumption of the current state about ON or OFF of the […]
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This is a simple circuit of Touch switch activated relay. This circuit is used to turn on/off electronic relay using touch sensor. This circuit consist of two main parts, they are a decimal counter and an current amplifier circuit. This circuit is need a 5volts power supply. Here is the circuit: As the counter circuit, this circuit uses JK flip […]
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This 555 circuit will activate a buzzer and turn on a LED lamp when you touch the probe. Here is the circuit’s schematic diagram: lf you touch the plates, the lamp and the buzzer will be activated for a predetermined time period. The time period is determined by 100k resistor and the 10uF capacitor. You can easily change the value […]
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We can make a simple touch switch using only two inverter gates, two resistors, and two capacitors. The schematic diagram of the circuit is shown in the figure below. At power up, the output (of U1A) will be high, and the inverting output will be low because U1A gate will be triggered to ground level by C2. After triggered, the […]
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Many efforts has been made to make simpler circuit, and here is one result, a very simple touch switch. You can build up to 6 similar circuit using only one 4050 chip. If you touch the “on” pad, the output will be on on remains on until you or some one the “off” pad. Here is the circuit schematic diagram: […]
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