[sdiy] Square to Sine

[Magnus Danielson]

Hi Elain,

On 04/04/2017 08:32 PM, Elain Klopke wrote:
>
>         I'm assuming that the circuit would go something like this:
>         output from
>         PIC -> RC network chain -> Non-inverting amplifier -> 4066
>         switch matrix
>
>         I'm thinking the non-inverting amp since the resistors for the gain
>         aren't dependent on the resistors involved in the filter networks.
>         Unless of course I'm entirely wrong on how that works...
>
>
>     Exactly. Straight and simple.
>
>     Cheers,
>     Magnus
>
>
>
> I.... I got something right?! I'm actually learning things!

Yay! :)

The input of the op-amp can have pretty darn high impedance. When you 
setup your op-amp to have non-invertive gain, you have only the op-amp 
input as load for the circuit, and for this case you can use that 
regardless if you do gain 1 for buffering or hgher gain to compensate 
that filter frequency was low to cut of also some of the fundamental.

Cheers,
Magnus