Is there is another cheapest way instead of using linear optocoupler like il300 and do the same function

 

How about, Led attached to a photocell via a heat shrink tube?

 

How about, Led attached to a photocell via a heat shrink tube?

I need to be linear

 

I need to be linear

I don't think so. The photo transistors need to be matched.
https://people.ece.cornell.edu/land/courses/ece5030/labs/s2014/clareAN107.pdf

 

Here's a little blurb I wrote on that very subject.

 

Here's a little blurb I wrote on that very subject.

Is this ok if I use it to sence the voltage feedback, it will be very fast response to the input

 

I don't think so. The photo transistors need to be matched.
https://people.ece.cornell.edu/land/courses/ece5030/labs/s2014/clareAN107.pdf

Here's a little blurb I wrote on that very subject.

Did you use isolated delta segment converter to do the same like linear optocoupler

 

Is this ok if I use it to sence the voltage feedback, it will be very fast response to the input

I have no idea.
What is "very fast"?
What are you trying to do?
What signal are you trying to send through the opto?

 

I don't think so. The photo transistors need to be matched.
https://people.ece.cornell.edu/land/courses/ece5030/labs/s2014/clareAN107.pdf

Thanks so much , I need to use something cheaper than linear optocoupler. Did you use isolated delta segment converter

 

I have no idea.
What is "very fast"?
What are you trying to do?
What signal are you trying to send through the opto?

I need to sense the voltage feedback , that why I need the sensed voltage linear and fast response

 

I need to be linear

http://www.goldmine-elec-products.com/prodinfo.asp?number=G15396

Cost about $1.00. Cheaper in small quantity.

 

View attachment 113070


http://www.goldmine-elec-products.com/prodinfo.asp?number=G15396

These use Cadmium Sulfide (CDS) sensors, very slow and highly non-linear.

 

I need to sense the voltage feedback , that why I need the sensed voltage linear and fast response

That tells me nothing useful.
Is "fast" milliseconds, microseconds, nanoseconds, picoseconds...?
Sense voltage feedback from what?
Please answer my questions in post #8 if you want any further help.
Post a diagram of what you are trying to do.
You lack of more specific information makes it impossible to help you further.

 

See

 

These use Cadmium Sulfide (CDS) sensors, very slow and highly non-linear.

Over what range do you need linearity? Input voltage, output voltage, current, resistance? You might find something with a workable region.

 

See
View attachment 113079

That also uses a specialized opto isolator which the OP wants to avoid.

 

That tells me nothing useful.
Is "fast" milliseconds, microseconds, nanoseconds, picoseconds...?
Sense voltage feedback from what?
Please answer my questions in post #8 if you want any further help.
Post a diagram of what you are trying to do.
You lack of more specific information makes it impossible to help you further.

Sorry Crutschow,
This basically DC DC bidirectional ,the input to the primary is 40-100VDC and the output from the secondary is 500-1000VDC ,the switching frequency is 65Khz ,i need to sense the output voltage from the secondary side, the control is in the primary side,

 

See
View attachment 113079

Can i get the LT spice model for the linear opto coupler HCNR200, is this you create it or you download it?

 

The model can be found here.

 

I need to be linear

Its described in some appnotes - you need 2 optocouplers; one is your isolated signal path, the other is the feedback loop controlling the op-amp driving the IRLEDs. The 2 IRLEDs are in series so they carry identical current.