> I have a linear signal that goes from +0.45V to +1.15V. I
> need to convert it to a signal that is +0.3V, when level
> is +0.45V and +10V when the signal is +1.15V.
> Could somebody suggest an op-amp circuit that would do
> this. Would I need some type of offset to get this
> "strange" range? I tried using a regular "non-inverting
> op-amp circuit", but I couldn't get the full range. I am
> using a R-R op-amp with +10V as the positive supply.
> Steve

I can't figure out why I see no replies. Anyway, to get started,
run the input signal to the non-inverting input, then create a
reference voltage (your "some type of offset") by making a voltage
divider with two resistors to get something in between. (.3+1.15)/2
Figures out to .72 V.  Tie that to the inverting input and now it
will switch as it crosses the reference point.

Did it need to still be linear?  Reduce the gain of the op amp
with a feedback resistor from the output to the inverting input.
This will upset the offset but it will get you started if you
are going nowhere.  There's more to do but maybe this will
kick off a discussion, if you still need it and I didn't miss
the whole thread somehow.

I just noticed you said you had a circuit.  Maybe post a link
to that and we can look at it.  Probably you just need to
up the gain by adjusting the resistors in the feedback path
from output to inverting input.

Barry

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