what is a optocoupler?
Do you know what is optocoupler and how does optocoupler work? Optocoupler is actually a combination of LED and phototransistor. Optocoupler is used to provide feedback from output to input so that the result of output will be stable. In this article the admin will discuss about understanding optocoupler and the working principle of optocoupler
An example of using optocoupler can be found on the phone charger. In a good quality phone charger is usually always equipped with an optocoupler
By using optocoupler then the output on the mobile phone charger will be exactly 5VDC even though the input voltage is fickle
Optocoupler usually has 4 legs with 2 legs as input and 2 other legs as output. But there is also an optocoupler that has more than 4 feet
In the optocoupler electronics circuit the symbols with the following picture
the parts of optocoupler?
what are the optocoupler parts? Optocoupler consists of two parts of the sender and receiver and both are isolated
part sender optocoupler is an LED as a light transmitter and the receiver is a phototransistor that serves to detect light
photo transistor is a component made of a semiconductor that serves to convert light signals into electricity
how photo transistor works is similar to LDR
read also what is a LDR and how the LDR works
After you know about the parts of optocoupler then you need to know how optocoupler works
how does optocoupler work?
How does optocoupler work? To make it easier to understand how the optocoupler I will take the example of a mobile charger
On the phone charger there are 2 parts of the hot part and cool part
the hot part is the charger part of the phone that will cause an electric shock when touched while the cool will not cause electric shock when touched
Can also be interpreted the hot part is the part that is connected to AC 220V while the cool part is the part that the output that produces voltage 5VDC
The hot part is the input and the cool part is the output
In the hot phone charger there is a series of diodes, capacitors, and transistors
Well the optocoupler is placed between the hot part and the cool part
As you have already known, the mobile phone charger must issue a proper voltage of 5VDC in order to work optimally
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Optocoupler will provide feedback when there is an increase in voltage or voltage drop
When there is a voltage drop the optocoupler will inform the input that the output voltage must be raised
Similarly vice versa when there is an increase in voltage then optocoupler will provide information that the output voltage should be lowered
The information provided to optocoupler is electrical signal that is signal from LED sent to photo transistor
Why use optocoupler?
maybe you still asked why use optocoupler? Why not use resistors?
The reason why using optocoupler is isolation
In the above explanation explained that the input and output of optocoupler using LED and phototransistor and mutually isolated
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Thus the optocoupler is safely used in hot and cool areas
In this way a precise 5VDC voltage will be obtained
The use of optocoupler not only on mobile phone charger only. Optocoupler can also find on TV, VDC, PC and so on