EL817 PHOTOCOUPLER PDF

Figure 1 shows the basic form of such a device. Here, the Tx unit is a LED, but the Rx unit may take the form of a phototransistor, a photo-FET, an opto-triac, or some other type of photo-sensitive semiconductor element; the Tx and Rx units are housed closely together in a single, sealed package. Basic form of an optocoupler device. Basic form and application circuit of a typical optocoupler.

Author:Mijas Fenrigar
Country:Cameroon
Language:English (Spanish)
Genre:Politics
Published (Last):16 July 2014
Pages:466
PDF File Size:16.39 Mb
ePub File Size:13.59 Mb
ISBN:658-3-90121-902-7
Downloads:26301
Price:Free* [*Free Regsitration Required]
Uploader:Akitaur



This IC is used to provide electrical isolation between two circuits, one part of the circuit is connected to the IR LED and the other to Photo-transistor. The digital signal given to the IR LED will be reflected on the transistor but there will be no hard electrical connection between the two. This comes in very handy when you are trying to isolate a noisy signal from your digital electronics, so if you are looking for an IC to provide optical isolation in your circuit design then this IC might be the right choice for you.

Then Pull high the collector pin of the transistor using a resistor here I have used 1K and connect the collector pin to the output of your desired logic circuit. The Emitter pin 4 is grounded. This is where the isolation occurs. There pull-up resistor 1K acts as a load resistor. But when the Logic input is made high, this high voltage should be a minimum of 1. This will short the collector and emitter and hence the Logic Output voltage will become zero. This way the logic input will be reflected at the logic output and still provides and isolation between the two.

The complete working can also be understood form the GIF file above. Another important parameter to consider while using an Optocoupler, is the rise time tr and fall time tf. The output will not get high as soon as the input logic is made low and vice versa.

The below waveform shows the time taken for the output to transit from one state to another.

EINAUDI NIGHTBOOK PDF

EL817 Phototransistor Photocoupler

Halogens free. Compact small outline package? Pb free and RoHS compliant. UL approved No. VDE approved No. SEMKO approved? NEMKO approved?

ANUALPEC 2013 PDF

Optocoupler Circuits

This IC is used to provide electrical isolation between two circuits, one part of the circuit is connected to the IR LED and the other to Photo-transistor. The digital signal given to the IR LED will be reflected on the transistor but there will be no hard electrical connection between the two. This comes in very handy when you are trying to isolate a noisy signal from your digital electronics, so if you are looking for an IC to provide optical isolation in your circuit design then this IC might be the right choice for you. Then Pull high the collector pin of the transistor using a resistor here I have used 1K and connect the collector pin to the output of your desired logic circuit. The Emitter pin 4 is grounded. This is where the isolation occurs.

Related Articles