Quick Answer: Can An LED Be Used As A Photodiode?

Can I use LED as diode?

Practically, LED can not be used as diodes.

Reverse voltage rating (PIV rating) of LEDs is less than 5-10 volts, which is not enough for most of the applications.


Reverse leakage current even for low reverse voltages (less than 5-10 volts) is too large for LEDs..

What type of diode is an LED?

The “Light Emitting Diode” or LED as it is more commonly called, is basically just a specialised type of diode as they have very similar electrical characteristics to a PN junction diode. This means that an LED will pass current in its forward direction but block the flow of current in the reverse direction.

What are the two basic types of LEDs?

The two basic types of LEDs are indicator-type LEDs and illuminator-type LEDs. Indicator-type LEDs are usually inexpensive, low-power LEDs suitable for use only as indicator lights in panel displays and electronic devices, or instrument illumination in cars and computers.

What is the difference between a phototransistor and a photoresistor?

Following table mentions difference between photoresistor and phototransistor….Difference between photoresistor and phototransistor.FeaturesPhotoresistorPhototransistorResponsive to lightLessMoreMaximum Resistance in darknessLowerHigherMinimum resistance in bright lightHigherLowerCurrent carrying capacityHigher (Twice)Lower5 more rows

Can a phototransistor receive light from an LED?

An LED and a phototransistor are sealed in a light-proof plastic package, so that light from the LED is received by the phototransistor. When the LED is turned on by a current supplied from an external source, the phototransistor is turned on. If the phototransistor is wired as a switch, this can turn on other devices.

What resistor do I need for LED?

The resistor must have a value of at least 183.3 ohms. Note that the voltage drop is 5.5 volts. It would have been possible to connect additional LEDs in the circuit.

Why is led not made of silicon or germanium?

LEDs are p-n junction devices constructed of gallium arsenide (GaAs), gallium arsenide phosphide (GaAsP), or gallium phosphide (GaP). Silicon and germanium are not suitable because those junctions produce heat and no appreciable IR or visible light. … An exposed semiconductor surface can then emit light.

What is the symbol of photodiode?

PhotodiodeOne Ge (top) and three Si (bottom) photodiodesTypePassiveWorking principleConverts light into currentPin configurationanode and cathodeElectronic symbol1 more row

What is the difference between simple pn junction diode and LED?

The most significant difference between the LED and diode is that the LED emits the light while the diode allows the current to flow only in one direction and opposes the flow in the opposite direction.

What is difference LED and photodiode?

LED and Photodiode are reverse of each other. LED generates light with the help of charge carriers while photodiode generates current due to incident photons. In a nutshell, LED converts electric energy into light energy but Photodiode converts light energy into electrical energy.

What can I use instead of a diode?

What can be used in place of diodes? You can make a synchronous rectifier, one that senses the voltage difference and opens or closes a MOSFET.

What is dark resistance of photodiode?

[′därk ri‚zis·təns] (electronics) The resistance of a selenium cell or other photoelectric device in total darkness.

What are the two types of LED configurations?

LED configurationsSingle colour: This is the standard format or configuration for an LED. … Bi-colour LEDs : This format for LEDs uses a pair of LEDs wired in an inverse parallel formation. … Tri-colour LEDs : This LED configuration again uses two separate LEDs, but in a different configuration.More items…

Is led a photodiode?

In addition to emitting light, an LED can be used as a photodiode light sensor / detector. … As a photodiode, an LED is sensitive to wavelengths equal to or shorter than the predominant wavelength it emits. A green LED would be sensitive to blue light and to some green light, but not to yellow or red light.

What is difference between Photodiode and phototransistor?

The photodiode is a semiconductor device which converts the light’s energy into an electrical current. Whereas, the phototransistor uses the transistor for the conversion of light energy into an electrical current. The phototransistor generates current whereas the photodiode produces both the voltage and current.