Hello,

I look for a scheme allow me to sync my output with the main voltage(230V).
I mean that my output will be a 0-5V signal

 

Search on zero crossing or zero crossing trigger. There are lots of options. John

 

i want a square wave circuit() synchronous with the main power and not a zero crossing detector.

 

One viable solution has been presented to you. I'd recommend you investigate that solution.

 

Your search on zero crossing should have yielded circuits based on voltage comparators where the reference is zero. That gives you a square wave of the same frequency and in sync, except for a small delay dependent on the comparator. How close to sync do you need? John

 

If it were me, I'd use a zero-crossing detector to synchronize the square wave with the line frequency.