PC Transistor Output Optocouplers are available at Mouser Electronics. Mouser offers inventory, pricing, & datasheets for PC Transistor Output. Sharp Microelectronics, Transistor Output Optocouplers OPTOISOLATOR 5KV TRANS 4ESOP, Optoisolator Transistor Output 1 Channel. Datasheet, 7, Optocoupler Tutorial about how Optocouplers and Opto-isolators use light to electrical isolate its input signal from its output signal.

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You need a pull-up resistor at pin 4.

In choosing appropriate values for R1, the value for the current limiting resistor is set pc817 optocoupler produce the correct forward current I F through pc817 optocoupler infrared LED in the optocoupler.

Although this example describes the design of a simple interface pc817 optocoupler two HCT logic circuits, the difference between the results achieved here and those needed for any other optocoupler are that similar calculations can be made just using data appropriate to other voltages and currents and other optocouplers.

I am using the same setup, different kind of optocouplerr and it is working. Bipolar Junction Transistors 4. You contribute a lot to the site but I think that you go over the pc817 optocoupler of the OPs quite often using acronyms, initialisations and electronic concepts that the users may not have come across.

There pc817 optocoupler of course, more useful applications for an optocoupler than simply isolating one logic IC from another. The output current available from a HCT gate to drive the optocoupler input is limited to 4mA, which is pc817 optocoupler optocoupleer for driving an optocoupler. These calculations look OK. Bring 12 V to 3. The problem is lessened by ensuring that the external circuit is fully isolated from the computer and an optocoupler such as the PC is a cheap and effective assuming no major user errors solution.

Using Opto Couplers

Each logic family e. Also at higher frequencies amplitude of the output signal reduces markedly. By clicking “Post Your Answer”, you acknowledge that you have read our updated terms of serviceprivacy policy and cookie policyand that your continued use of the website is subject to these policies.


I cannot post the schematics but i can tell you the resistor value. I’ve already said – because you’re trying to use a voltage divider as a regulated power supply. There are many different applications for optocoupler circuits, pc817 optocoupler there are many pc817 optocoupler design requirements, but a basic design for an optocoupler providing isolation for example between two circuits, simply involves the choice of appropriate resistor pc817 optocoupler for the two resistors R1 and R2 shown in Fig.

Assuming that a single HCT pc817 optocoupler is only feeding this optocoupler, a logic 1 voltage of about 4. The 1 K value on pin one is fine, but increase the value of resistor to k between Pin 4 and 3. Sign up using Email and Password.

Because the CTR of an optocoupler can be expected to reduce over time, it is common practice to choose a value for I F somewhat lower than the maximum, so that the intended performance can still be achieved over the intended lifetime of the circuit.

Pc817 optocoupler this is wrong can you suggest me another circuit? I mean if I make this connection in real, will this work?

I might be wrong too. Pc817 optocoupler is more than the 5mA minimum required to drive the 2N into saturation. It looks to me like you will probably achieve about 3. If you have a 1k resistor on the output that you hope to have 3V3 across it means an output current Ic of 3. Now coming to collector load resistor pc817 optocoupler which is not mentioned in the image, in data sheet the Vce saturation voltage is 0.

Using the data in Table 5. It would also be possible pc817 optocoupler replace R13 pc817 optocoupler a constant current source. By using our site, you acknowledge that you have read and understand our Cookie PolicyPrivacy Policyand our Terms of Service.

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An extra few moments writing complete English sentences subject – verb – object would help too. This simple interface has one more safety feature; diode Pc817 optocoupler connected across the motor will effectively prevent any nasty back EMF spikes generated by the inductive load the motor from causing damage pc817 optocoupler the interface.

Can you check my calculation based on your response as well as based on response in the comment section. Post as a guest Name. Sign up pc817 optocoupler Facebook. Manufacturers will normally quote a range of CTR values for different output phototransistor collector voltages Pc817 optocoupler C and different ambient temperatures T A The CTR will also vary with the age of the optocoupler, as the efficiency of LEDs decreases with age over s of operating hours.


Ideally you should have a pull up resistor. What is the pull down value? If you supply a schematic with values as you use it, we will be able to offer much better answers much quicker. Typical optocouplers can handle input and output currents from a few microamps to tens of milliamps.

This site uses cookies to deliver our services and to show you relevant ads and job listings. The main purpose of an optocoupler interface is to completely isolate the input circuit pc817 optocoupler the output circuit, which normally means there will be two completely separate power supplies, one for the input circuit and one for pc817 optocoupler output. By using our site, you acknowledge that you have read and understand our Cookie PolicyPrivacy Policyand our Terms of Service.

Pc817 optocoupler the optocoupler should in this case act as though it is invisible, that is the HCT gate connected to the pc81 output should see an available current of up to 4mA, just as though it was connected to the output of another HCT gate.

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Is this thing correct.?

If you can’t take a screenshot of the relevant bit, use the pc817 optocoupler cp817 schematic editor to redraw it. How to get 3. If you have 12V feeding the input diode pc817 optocoupler 1K you will be producing a forward current of about 10mA.

The graph in Fig. You have both sides sharing a common ground, therefore they’re not isolated, therefore why pc817 optocoupler you need the opto-isolator?