Gajendran Rao
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Transcript of Gajendran Rao
GAJENDRAN RAO
A14KE0064
Understanding on OPTOCOUPLER
The above IC is the OPTOCOUPLER wich is consisting 6 pins and covered by poxy
Functions
Usually put in between HIGH voltage circuit and LOW voltage circuit These to isolate the HIGH voltage circuit and LOW voltage circuit directly contacted by each
other Moreover, by putting these OPTOCOUPLER between HIGH voltage circuit and LOW voltage
circuit it will prevent the LOW voltage circuit components from destroyed if there is something goes wrong in HIGH voltage circuit.
Its has the same concepts of circuits relay
The optocoupler ic configuration
These ic was integrated by using simple components which is infrared LED which was realy tiny and its work under 1.2 volts and about 20 miliampere.( HIGH voltage circuit is connected to these part)
Its also have phototransistor (LOW voltage circuit is connected to these part)
The OPTCOUPLER working principals
When at input part have HIGH voltage supply the OPTOCOUPLER is connected then other part is connected with LOW voltage circuit.
When the infrared LED receive currents from HIGH voltage supply it will emits infrared lights to the phototransistor.
The phototransistor will detect the emmited light at base cousing it to be switched on and work as normal bipolarjunction transistor
As we see in the circuit above the base phototransistor is connected to a resistor and then to ground this is because to control the sensitivity of the switch on the LOW voltage circuit and make it more stable.
We can also connected the BASE to the ground strainght way but the swicthing of the cuircuir will not stable.