hello there
i have to do a project at my school and i need some help.the project is that i should design a circuit with amplifiers,converter dc to dc,sine signal from 2,5-5 volts and should convert it to the output in sine signal from 0-6 volts and it should be in the same phase as the input signal.i was thinging to do it with operational amplifier,but how i will take the output 0 volts when i give in the input 2,5 volts should i use voltage divider?i am confused any help will be apreciatable

 

Its a bit difficult to make up what you are trying to do from your post. Be more precise and don't write your text in clusters that are difficult to decipher. Paragraphs and good sentances are your friend

 

On another website, I questioned his poor English and he explained with more details. Then I thought he wants an "expander" circuit.

It also might be a "voice gate" circuit that mutes when the input signal is low.

I asked twice but he did not say the function of the DC to DC converter.