im working to a special project
the thing is i wana be able to active my 9v circuit ( completly independent ) from a output of 1.5v
so the 1.5 on ( a LED ) is active i wana be able to active the 9v circuit
any sugestion ?

 

I don't like to nitpick but someone has to tell you.

A subject title of "need help please" is of no help to anyone. Try to be more descriptive in your subject title.

Even if English is a Second Language (ESL) for you, it displays laziness on your part when you write with poor spelling, grammar and punctuation.

Proper communication skills matter.

 

What do you mean "completely independent"?
Can the circuits share a common ground?

 

Most optocouplers can be activated by 1.2v on their inbuilt LED.

 

What is this mystical '9V circuit'? How much current does it draw?

 

i dont think the questions about isolation (apologies if im wrong), think the OP just wants a 1.5V single to trigger something on a 9v rail, if this is the case a npn transistor will do