4-channel optocoupler IC

I'm using a circuit with Arduino Nano and a couple of 4N35 optocoupler ICs which works great for controlling focus and shutter on a camera.

Now I want to add two additional optocouplers. So, instead of using 4 x 4N35's I'm looking for a 4-channel optocoupler IC.

I found several online but I'm not sure which one to use. Here's a couple I found:

TLP521−4 ILQ615 which comes in 4 different versions

Which one should I use???

Probably the easiest to get and cheapest. Unless you have a specific specialised project, they would both appear to be suitable.


Why are you asking ? All the specs are on the datasheet. Do you not know how to read the datasheet or what to look for ? What you are asking is like asking what kind of car to buy. It depends on your application . Do you , or do you not know which parameters to look up on the datasheet and how to use them ? If the answer is " yes" then the cost is the only factor . A camera shutter circuit is neither high speed or high current so it's sort of like asking what brand of peanut butter you should buy. If you are already using optocouplers it doesn't necessarily imply you know how to read or use the datasheet. You have to tell us that. So after comparing the specs, which one better suits your application ? ( or , is THAT , in fact , what YOU are REALLY trying to ask US ?) I'm prefer Vishay products and I drive a Hummer.


Thank you for your input Weedpharma.

@raschemmel: what's wrong with you? I said it's for controlling camera focus & shutter. If I knew how to read datasheets I wouldn't be asking. That's the beauty of Arduino, you don't have to be an electronics expert to use it. Even someone like me who barely understands how to connect components & modules can create nice projects.

The 4N35 is from Vishay; might be worth digging on their site to see if there's a "4x4N35-in-1".

@raschemmel: what's wrong with you? I said it's for controlling camera focus & shutter.

which is why I said :

A camera shutter circuit is neither high speed or high current so it's sort of like asking what brand of peanut butter you should buy

which is the same as

Probably the easiest to get and cheapest.

do you see any difference between the two ?

Skippy or Jiff ?

If you are not going to post a schematic of your circuit we have no way to know if you know what changes you need to make to your circuit for the 4-channel optos. You only asked which to buy. You didn't ask what to change and you didn't say if you knew or didn't know how to design the circuitry for the 4-channel optos. Were you planning to use the same resistor values without doing any calculations ? It would probably work , but it would be better to look up the specs and do the math. The forward current is the same or close to the same for all three chips (4N35 and the other two) If you are going to post here you might as well ask how to read the datasheet so next time you can figure it out for yourself. (if you want to learn) There's nothing wrong with me. You are the one asking for help so you are the one who needs to tell us exactly what help you need. I asked you a simple question. Do you know how to read a datasheet ? How am I supposed to know if you do or don't if you don't say so ? You answered (in your own rather rude way) "NO" . So that being the case, how do you expect to use the 4-channel optos if you don't know what specs to look up and what to do with them. If you want help , tell us exactly what you need the help with. Asking us which to buy isn't going to tell you how to use it. If you know how , fine. If not , say so. we shouldn't have to play 20 questions here. You post should have stated:

"I need to switch from pair of single optos to a 4-channel opto chip. Here is my current circuit schematic using the 4N35. Which chip should I buy and what changes do I need to make to my circuit ?"

I have used these: https://www.sparkfun.com/datasheets/Components/ps2501.pdf

CTR is good @ 300%+

OP doesn't know ( or want to learn) how to read a datasheet because he has us.(so he says) He doesn't want to know what CTR is.


If you barely understand how to connect components it's your fault. We're here 24/7/365. It's not rocket science If you learn one thing a day....

@raschemmel: Maybe you’re right about providing more info, I do understand the basics of how to connect the optocouplers and calculate the resistor values. My question was more about the suitability of the ICs for the task. Vishay for example has a full page of different optocoupler models and I just wanted to make sure I didn’t pick the wrong one.

Like I said, for your apolication it doesn't matter.

Optocouplers come in standardised families. If you have a dual optocoupler that’s working then that same part number with a “4” instead of a “2” will probably function exactly the same except there’s 4 optocouplers.

Not every family has a full set of single-dual-quad and if yours doesn’t then just buy two of the duals.

The parameters in the datasheet and the design methods are surprisingly complex for optocouplers. If you’re not an electrical engineer and don’t want to become one then just test with one and then always buy that same one after you find what worked.