# Sort out any voltage below 2 volt

I have an input, which varies from 0 to 12 volt, but I want to have it vary from 2 to 12 volt. So any volt below 2 volts should come out as 0 volt instead.

I have looked into op amps, but I can't see how a comperator will solve this problem.

Thanks!

Set up a comparator with a >2V threshold. And let that switch on the output when >2V. Or, depending on what you need to dive, set it up with a <2V threshold and short the output to 0V if <2V.

Aka, for a real answer we need to know more about the signal.

How accurate does it need to be? Do you mean any voltage below 2V appears as 0V, or do you mean
appears as 2V ? A diode clamping setup could do the later.

Bassusour:
I have an input, which varies from 0 to 12 volt, but I want to have it vary from 2 to 12 volt. So any volt below 2 volts should come out as 0 volt instead.

I have looked into op amps, but I can't see how a comperator will solve this problem.

Thanks!

There's a contradiction in what you wrote. You say you want to "have it vary from 2 to 12 volt". But, then you say that "any volt[sic] below 2 volts should come out as 0 volt instead".

So, do you want the output to vary from 0 to 12 volt, i.e. with the output holding at 0 until the input reaches 2V, then jumps up to 2V, and from there, tracks the input? I.e., a 2V stair step, with a unity gain.

OR, do you want the output to start at 2V, when the input is at 0V, and vary linearly to 12V as the input increases to 12V? Which, basically means the output will have an offset of 2V, and a gain of 0.83.

OR, if I take you literally, you want this thing to force a voltage, that would normally go from 0 to 12V, to, instead, go from 2V to 12V? And, if so, the next question might be, is this to be a one time occurance -- essentially Zapping it into a 2 to 12V compliance -- or is this source to be wrangled repeatedly? ;D

Three diode drops should change your input from 0-12 volts to 0 to 10 volts

noweare:
Three diode drops should change your input from 0-12 volts to 0 to 10 volts

Except, be aware that doing it this way is imprecise, and vulnerable to temperature changes, and probably doesn't meet the requirement, since it seems pretty clear that the max output voltage is meant to be 12V, and this method would only net a 10V max. Also, the forward drop on a diode, though somewhat stable, does still vary with current. And, it's not established what sort of impedances are required. This is a fairly low impedance solution.