New
DZD 1,300.00
Optoelectronics
152 results
Optoelectronic components for your projects: 3mm and 5mm LEDs, infrared emitters and receivers, 7-segment and LCD displays, optocouplers and LDR photoresistors.
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152 results
17 available
New
P2026100871
4-Pin Photodarlington Optocoupler KP4010
DZD 150.00
New
P2026100870
MCT271 Optocoupler
DZD 150.00
New
P2026100869
QTC4502 Optocoupler
DZD 150.00
New
P2026100868
PC714 Optocoupler
DZD 150.00
New
DZD 150.00
New
P2026100866
CNY17-2 Optocoupler
DZD 150.00
New
P2026100865
CNY17-4 Optocoupler
DZD 150.00
P2026080631
0.91-Inch OLED Display
DZD 950.00
P2026080630
1.8 Digital TFT Display 128*160
DZD 1,450.00
P2026080606
Incandescent Festoon Bulb 12V 40mA
DZD 100.00
P2026080605
Incandescent Festoon Bulb 12V
DZD 100.00
P2026070327
LED BADGE
DZD 2,000.00
P2026070327
LED BADGE
DZD 2,000.00
P2026070262
PC814BS Optocoupler SMD-4P
DZD 85.00
P2026070262
PC814BS Optocoupler SMD-4P
DZD 85.00
Choosing your optoelectronic components
Optoelectronics covers everything that turns current into light, or light into an electrical signal. For a signaling LED, the choice depends on diameter (3mm or 5mm), color and brightness: a high brightness LED is visible in a lit room, while a standard colored LED is enough for a front panel indicator. Every LED needs a series resistor calculated from the supply voltage and its threshold voltage, which is higher for blue and white than for red. In SMD, the 0603, SM0603 or PLCC3528 packages are soldered onto a circuit board.
For detection and remote control, components work in pairs: an 850 or 940nm infrared emitter LED facing a receiver LED, a demodulated receiver such as the VS1838 for remote controls, or a reflective sensor like the TCRT5000 to follow a line or count turns. A GL5528 photoresistor simply measures ambient light.
- Displays: 1, 2 or 4 digit 7-segment displays, MAX7219 matrix, character LCD or TFT — see Display modules.
- Galvanic isolation: a optocoupler PC817 or CNY17 for a logic signal, a MOC3023 or MOC3083 to drive a triac on the mains, with the MOC3083 featuring zero-crossing detection.
- LEDs and infrared: full details in LEDs, matrices, infrared and 7-segment displays.
Frequently asked questions
Which resistor should be used in series with an LED?
Subtract the LED's threshold voltage from the supply voltage, then divide by the desired current, often 10 to 20 mA. Under 5V, a red LED requires a higher resistance than a blue or white LED, whose threshold voltage is close to 3V.
What is the difference between an infrared receiver LED and a VS1838 receiver?
The 940nm receiver LED is a simple photodiode or phototransistor: it produces a current proportional to the infrared light received. The VS1838 additionally integrates a filter and a 38 kHz demodulator, which makes it suitable for decoding remote controls.
What is an optocoupler like the PC817 used for?
It transmits a signal between two circuits without any electrical connection between them, using an LED and a phototransistor in the same package. It is used to protect a low voltage board from a power section, or to link two different grounds.
Common cathode or common anode 7-segment display?
With common cathode, all cathodes are connected to ground and each segment lights up with a high level; with common anode, it is the opposite. The choice depends on the driver or microcontroller used, the two are not interchangeable.
Why does the price vary so much from one LED to another?
Brightness, wavelength, package (through-hole or SMD) and manufacturer make the difference. A standard signaling LED remains inexpensive, while a calibrated high brightness LED or a multi-digit display cost more.