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Friday, December 8, 2023

PROXY SENSOR . distance sensor . car distance sensor . car distance sensor proximity sensor . DIY


 PROXY SENSOR . distance sensor . car distance sensor . car distance sensor proximity sensor . DIY

It is a simple and useful circuit made with LM3914 Integrated proximity sensor with LED indicator, which I believe will be useful to you. I wish you a good time.


Proximity sensor, which I believe will be useful for you, and a simple and useful circuit made with lm3914 Integration with led display, I wish you a good time.

A tutorial on How to make an InfraRed (IR) proximity sensor circuit along with detailed explanation on how the circuit works. The sensitivity or Range of detection can also be controlled by adjusting the potentiometer.


1.LM 358IC

2.1 InfraRed LED PhotoDiode pair

3.Resistors: 470, 270R, 10K

4.Potentiometer: 10K

5.pcb or breadboard

6.9v battery and clip

7.led

8.buzzer

9.ic base

The sensing component in this circuit is IR photo-diode. More the amount of InfraRed light falling on the IR photodiode, more is the current flowing through it. (Energy from IR waves is absorbed by electrons at p-n junction of IR photodiode, which causes current to flow)


This current when flows through the 10k resistor, causes potential difference (voltage) to develop. The magnitude of this voltage is given by Ohm's law, V=IR. As the value of resistor is constant, the voltage across the resistor is directly proportional to the magnitude of current flowing, which in turn is directly proportional to the amount of Infra-Red waves incident on the IR photodiode.


So, when any object is brought nearer to the IR LED, Photo-Diode pair, the amount of IR rays from IR LED which reflects and falls on the IR photodiode increases and therefore voltage at the resistor increases (from the deduction in previous para) .

We compare this voltage change (nearer the object, more is the voltage at 10K resistor / IR photodiode) with a fixed reference voltage (Created using a potentiometer).


Here, LM358 IC (A comparator/OpAmp) is used for comparing the sensor and reference voltages. The positive terminal of photodiode (This is the point where the voltage changes proportion to object distance) is connected to non-inverting input of OpAmp and the reference voltage is connected to inverting input of OpAmp.


The OpAmp functions in a way that whenever the voltage at non-inverting input is more than the voltage at inverting input, the output turns ON.


When no object is near the IR proximity sensor, we need LED to be turned off. So we adjust the potentiometer so as to make the voltage at inverting input more than non-inverting.


When any object approaches the IR proximity sensor, the voltage at photodiode increases and at some point the voltage at non-inverting input becomes more than inverting input, which causes OpAmp to turn on the LED.

In the same manner, when the object moves farther from the IR proximity sensor, the voltage at non-inverting input reduces and at some point becomes less than inverting input, which causes OpAmp to turn off the LED.


 PROXY SENSOR . distance sensor . car distance sensor . car distance sensor proximity sensor . DIY

It is a simple and useful circuit made with LM3914 Integrated proximity sensor with LED indicator, which I believe will be useful to you. I wish you a good time.


Proximity sensor, which I believe will be useful for you, and a simple and useful circuit made with lm3914 Integration with led display, I wish you a good time.

A tutorial on How to make an InfraRed (IR) proximity sensor circuit along with detailed explanation on how the circuit works. The sensitivity or Range of detection can also be controlled by adjusting the potentiometer.


1.LM 358IC

2.1 InfraRed LED PhotoDiode pair

3.Resistors: 470, 270R, 10K

4.Potentiometer: 10K

5.pcb or breadboard

6.9v battery and clip

7.led

8.buzzer

9.ic base

The sensing component in this circuit is IR photo-diode. More the amount of InfraRed light falling on the IR photodiode, more is the current flowing through it. (Energy from IR waves is absorbed by electrons at p-n junction of IR photodiode, which causes current to flow)


This current when flows through the 10k resistor, causes potential difference (voltage) to develop. The magnitude of this voltage is given by Ohm's law, V=IR. As the value of resistor is constant, the voltage across the resistor is directly proportional to the magnitude of current flowing, which in turn is directly proportional to the amount of Infra-Red waves incident on the IR photodiode.


So, when any object is brought nearer to the IR LED, Photo-Diode pair, the amount of IR rays from IR LED which reflects and falls on the IR photodiode increases and therefore voltage at the resistor increases (from the deduction in previous para) .

We compare this voltage change (nearer the object, more is the voltage at 10K resistor / IR photodiode) with a fixed reference voltage (Created using a potentiometer).


Here, LM358 IC (A comparator/OpAmp) is used for comparing the sensor and reference voltages. The positive terminal of photodiode (This is the point where the voltage changes proportion to object distance) is connected to non-inverting input of OpAmp and the reference voltage is connected to inverting input of OpAmp.


The OpAmp functions in a way that whenever the voltage at non-inverting input is more than the voltage at inverting input, the output turns ON.


When no object is near the IR proximity sensor, we need LED to be turned off. So we adjust the potentiometer so as to make the voltage at inverting input more than non-inverting.


When any object approaches the IR proximity sensor, the voltage at photodiode increases and at some point the voltage at non-inverting input becomes more than inverting input, which causes OpAmp to turn on the LED.

In the same manner, when the object moves farther from the IR proximity sensor, the voltage at non-inverting input reduces and at some point becomes less than inverting input, which causes OpAmp to turn off the LED.

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