Compared to a basic circuit, a simple long range infrared transmitter circuit may transmit infrared light over a longer distance by using easily accessible components.
The fundamental concept is to manipulate the infrared light emitting diode IR LED to produce pulses of light.
Most infrared receivers are built to detect a particular frequency that is generated by the IC 4047.
Range is improved by using additional LEDs in tandem or a higher power LED, which increases the total amount of infrared light emitted.
We may extend the infrared radiations emission range by up to 100 cm by utilizing this circuit.
Here ,it implies that we may use our long range IR transmitter circuit to expand the IR transmitting distance several times.
Circuit Working:
Parts List:
| Category | Item | Quantity | Power Rating |
|---|---|---|---|
| Resistors | 10k | 1 | 1/4 watt |
| 2.2k | 1 | 1/4 watt | |
| 10Ω | 1 | 1/4 watt | |
| Potentiometer | 10k | 1 | – |
| Capacitors | Ceramic 470pF | 1 | – |
| Electrolytic 100μF 25V | 1 | – | |
| Semiconductors | IC 4047 | 1 | – |
| Transistor BC547 | 1 | – | |
| Transistor BC557 | 1 | – | |
| MOSFET BS170 | 1 | – | |
| Components | IR LED transmitter | 3 | – |
Increasing the Infrared Transmissions Power:
The range of infrared IR radiation is increased by this circuit.
We use three infrared LEDs wired in series to do this.
The circuits overall infrared light output is increased by this arrangement.
RC Combination and Oscillating Frequency Set the Pace:
On certain pins 2 and 1 of a specialized chip, the 4047 IC an external resistor and capacitor are connected.
Together, these parts form an RC circuit that produces a precise oscillation frequency, similar to that of a fast on/off switch.
Next, the bases of transistors Q1 and Q2 get this oscillating signal.
The Significance of Regularity:
It is decided to utilize the 4047 IC as it generates a frequency of 38 KHz.
Many infrared IR and radio frequency RF remote controllers operate on a frequency that is similar to this one.
Through ‘modulating’ or overlaying the data signal on top of this 38KHz carrier wave the circuit generates a more powerful output at this particular frequency.
To put it another way this selected frequency is encoded with the data we wish to send in order to improve transmission.
MOSFET for Reduction of Losses and Efficiency:
The oscillating signal that drives a MOSFET BS170 and transistors is likewise produced by the 4047 IC.
This MOSFET functions similarly to an electrical switch and has one important benefit over a conventional transistor, it lowers power loss.
The MOSFET is a more effective option in this application since transistors have a larger power loss.
A 100uF capacitor further aids in preventing voltage dips while turning the circuit on and off.
This capacitor provides a backup power supply to keep everything running smoothly.
A Clean Signal using a Darlington Pair:
The NPN BC547 and PNP BC557 transistors are combined to form a darlington pair, which is utilized to prevent distortion of the signal controlling the MOSFETs gate terminal.
This is required due to a certain electrical characteristic of MOSFETs that may impact the signal.
Prolonged Infrared Transmission:
The drain terminal of the MOSFET is linked to the three infrared LEDs.
The IR LEDs are illuminated when a signal is received at the gate of the MOSFET, which permits current to flow from the drain to the source.
In comparison to a typical IR LED circuit, the IR rays travel a significantly longer distance due to the higher power from the many LEDs and the selected frequency.
This makes it possible for an IR receiver device that is compatible to successfully receive the IR signal.
Formula:
The IC 4047 in astable mode with one resistor R and one capacitor C may be found using the following simplified formula:
Frequency = 1 / (8.8 * R * C)
where:
- Frequency is the output frequency in hertz Hz
- R is the resistance of the single resistor used in ohms Ω
- C is the capacitance in farads F
If you know the resistor and capacitor values for your circuit, you can use this formula to get the planned oscillation frequency.
How to Build:
To build a Simple Long Range IR Transmitter Circuit follow the below mentioned steps for connections:
- Gather all the components as shown in the circuit diagram above.
- Connect pin 1 to pin 3 of IC1 4047 through capacitor C1 and to one leg of P1 10k pot.
- Connect pin 2 to one leg of 10k pot through resistor R1.
- Connect pin 4, pin 5, pin 6 and pin 14 of IC1 4047 to positive supply of +9V.
- Connect pin 7, pin 8, pin 9 and pin 12 of IC1 4047 to ground.
- Connect pin 10 of IC1 4047 to base of transistor Q2.
- Connect collector of transistor Q1 to positive supply, base of Q1 to ground through resistor R2, emitter of Q1 to emitter of transistor Q2.
- Connect emitter of transistor Q2 to emitter of Q1, base of Q2 to pin 10 of IC1 4047, and collector of Q2 to ground.
- Connect a capacitor C2 to positive supply to ground.
- Connect MOSFET Q3 drain pin to positive supply through a resistor R3 and 3 IR LEDs in series, connect gate pin of Q3 MOSFET between emitter pins of transistors Q1 an Q2, connect source pin of MOSFET Q3 to ground.
Safety Measures:
- Before adding more intricate parts, try a simple circuit first.
- Use high quality parts to increase dependability.
- Immediately after touching electronic components, properly wash your hands.
- You can reduce the possibility of mishaps when constructing and operating an IR transmitter circuit by adhering to these safety precautions.
- Before turning the circuit on, make sure all of your connections are correct.
Conclusion:
To conclude, by combining many IR LEDs with a precisely selected oscillation frequency this long range IR transmitter circuit successfully extends the transmission range of infrared signals.
A clean control signal is ensured by a darlington pair, while efficiency is increased by the MOSFET.
Prioritize safety above all else when making and utilizing this circuit, and make sure to follow suggested guidelines.