Forgive my limited electronics background, but what is the purpose of the
RC component in this diagram?  I understand the purpose of the diodes,
but why would you use the RC component?  I would guess as a method to
reduce spikes and "slow down" the rate of change of the incoming signal?

Thanks in advance for increasing my electronics knowledge,
Adam

On Mon, 24 May 1999 09:39:54 +0530 Ravi Pailoor <chiptech@VSNL.COM>
writes:
> Along with RC filter use 2 diodes for clamping.
>
>           |   Max vtg of ADC input
>         ---
>          /\
>          -
>          |
> ----------------/\/\/\/\/--------
>          |            |
>        ---        ----
>         /\         ----
>         -            |
>         | GND   |
>
> Pailoor
> -
> Ross Bencina wrote:
>
> > Greetings O PICsters,
> >
> > I'm building a device for a friend that has a bunch of external
> (user
> > connected) (8 to 12bit) adc inputs (the current design uses a
> 16f84 and a
> > tlc542 adc). The box will be used in a "musical" environment. The
> adc inputs
> > will be (mostly) powered from the unit itself (ie resistive
> sensors, light
> > sensitive transistors circuits etc.). Sensors may be connected
> using longish
> > leads.
> >
> > As electronics isn't my strong point I'm looking for some advice
> on
> > how/whether to "protect" the inputs to avoid having the adc inputs
> fried. At
> > the moment I'm planning to connect simple (RC) lowpass filters at
> each
> > input. Other than noise I'm not sure what other potential "issues"
> could
> > arise (esd etc?), or whether I should even be worried about this
> in a
> > non-industrial context.
> >
> > Any comments would aid my understanding considerably,
> >
> > Thanks,
> >
> > Ross.
> > <rossb@audiomulch.com>
> >
> > .................................
> > http://www.audiomulch.com/~rossb/
>
> --
> Website : http://business.vsnl.com/chiptech
>

Adam Bryant (age 0x23)
abryant@peaktech.com (work)
adamdb@juno.com (home)
Parker, CO, USA
Robotics, RC Airplanes, anything using a PIC

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