How can I isolate the analog voltage?

Thread Starter

Mohamad Knight

Joined Mar 21, 2016
23
I want to measure voltage with pic microcontroller by this circuit and my question is
1- is this circuit is safe for microcontroller ?
2- how can I isolate the output of the circuit v(an) AN1 to the pin of the microcontroller AN1 ?

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MrAl

Joined Jun 17, 2014
8,390
I want to measure voltage with pic microcontroller by this circuit and my qustion is
1- is this circuit is safe for microcontroller ?
2- how I can to isolate the output of the circuit v(an) AN1 to the pin of the microcontroller AN1 ?
Hi,

Are you sure that is what you want to do? Or just isolate from the AC voltage? That's more typical.
 

crutschow

Joined Mar 14, 2008
27,477
I want to measure voltage with pic microcontroller by this circuit and my qustion is
1- is this circuit is safe for microcontroller ?
2- how I can to isolate the output of the circuit v(an) AN1 to the pin of the microcontroller AN1 ?
1- What do you mean "safe".
2- What type of "isolation" are you referring to?
 

Dodgydave

Joined Jun 22, 2012
10,041
Your Lm258 is only going to give out 12v, then its halved by the 10k resistors to 6V, is that too high for your micro???
if so lower the resistor R10.
 

Thread Starter

Mohamad Knight

Joined Mar 21, 2016
23
no my friend
Dodgydave
the output of the lm258 is about (1-3) volt
I sorry about my many questions
but if lm258 destroyed by high voltage or another problem
a high voltage may reashed to microcontroller and destroyed
Am i right ?
so i want to using optocouplers to overcome this problem
 
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