Inverter to non-inverter cct

[Gene Zumchak]

Jezz,

    Yes it works, and it is linear from -1 to +1.  It's so simple, you just
should have tried it, but it's nice that you asked because some others may have
need of it.

    When the pot is at the bottom, the non-inverting input is grounding and is
simply a unity-gain inverter.  When at the top it is a voltage follower.  The
non-inverting input is Vin, the inverting input is Vin and the output must be
Vin.  If you have need to go between an equal an opposite +V and -V you simply
go from the input of a unity inverter to the non-inverting input.  From the
non-inverting input to ground you put a switch (transistor, FET, transmission
gate.  When the switch is on it is unity inverting.  When the switch is off it
is unity non-inverting.

Gene Z.



Jezz Brookes wrote:

> I've scoured my collection of circuits but couldn't find a circuit I'm after
> but I've seen it somewhere. So naturally I turn to you guys for help
> (again!)
>
> I want a circuit that you can vary the gain from +1 to -1 (i.e. inverting)
> and I came up with this circuit (attached). Is it going to work?
>
>   ------------------------------------------------------------------------
>                  Name: Invert.gif
>    Invert.gif    Type: GIF Image (image/gif)
>              Encoding: base64