For good linearity you want to use the photovoltaic mode. Put the diode from
ground to the (-) input of a good op-amp, and ground the (+) input. Wrap a
feedback resistor, probably something like 1 meg, from the output to (-). The
op-amp wants to have low input bias current, and stable bias current over the
temperature range you use. Consider a FET or CMOS input amp.

If the output oscillates you may need some capacitance in parallel with the
feedback resistor. This RC product will set the maximum speed signals that can
be used.

SherpaDoug

--- In sensorforum@yahoogroups.com, Bruno Ferrarezi <bferrarezi84@...> wrote:
>
> I need to detect luminosity only.
>
>
>
> 2009/6/29 Douglas Butler <sherpadoug@...>
>
> >
> >
> > A lot depends on what you are looking for. Are you trying to detect a fast
> > pulse with accurate timing, or high frequency carrier? Are you detecting a
> > feeble signal in darkness. Are you looking for a signal buried in noise?
> > These different situations require very different signal conditioning.
> >
> > Basic tradeoffs are speed vs. sensitivity, speed vs. linearity, and
> > bandwidth vs. noise rejection.
> >
> > SherpaDoug
> >
> >
> > --- In sensorforum@yahoogroups.com <sensorforum%40yahoogroups.com>, Bruno
> > Ferrarezi <bferrarezi84@> wrote:
> > >
> > > Hello.
> > >
> > > I design a project and I need to know how can I do for conditioning
> > signal
> > > provide for a photodiode.
> > > Do you have some ideas about this?
> > >
> > > Att
> > >
> > > Bruno
> > >
> > >
> > > [Non-text portions of this message have been removed]
> > >
> >
> >
> >
>
>
>
> --
> Bruno Ferrarezi
> 9888-5737
>
>
> [Non-text portions of this message have been removed]
>