Looks okay to me. The opamp is in the follower configuration (- input to the
output) reference to the + input.
Yes, the opamp is pulling the input line to reference. If you want something
closer to vref, use a schottky diode instead of 1n4001.
Rick

Benjamin Bromilow wrote:

> Hi all,
>
> Does this circuit make sense to anyone? Someone very kindly drew it up for
> me and e-mailed it but it doesn't make sense to me! It is supposed to take a
> 2.5v ref, buffer it and limit the input line (going horizontally) to around
> this level.
> However, in my mind, there appears to be some problems. Perhaps the second
> comma is critical!  :o)..... Firstly, the op-amp doesn't appear to be in
> voltage follower mode which is my understanding of a buffer mode.
> Additionally, I'm not sure where any excess voltage is supposed to be
> "disposed" of other than through the op-amp output stage. Is this okay?
> Am I being dense here or am I missing something??
>
> Ben
>
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>                Name: temp.jpg
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