Robert Rolf wrote:
> Dwayne Reid wrote:
>   
>> My hope is that the currently selected analog channel is connected to 
>> the sample capacitor even while the a/d is disabled.
>>
>> Any thoughts?
>>     
>
> So why not code it both ways and see if there is any difference in the A/D
> output for input voltage extremes?
> The input MAY be connected through to the charge division cap,
> but it may still need time to settle the reference and charge balance divider tree.
>
> And remember that the BOD is a very power hungry device and should never be
> used in low power applications.
>
> Can you do the work using the A/D RC clock and using a 32khz clock for the program
> clock too?
>
> Robert
>   
I am certain that the input cap IS connected when the A/D is ON, but not 
when it is off.
If the input impedance is very low, you can connect for a short time; 
otherwise I leave
it on for 10mS+ before starting the conversion.

Yes, BOD uses some power, but certainly is worth it to ensure proper 
startup. I have
been burned a few times without it, especially remote sensors whose 
powerup schemes
are suspected to be poor at times.

--Bob A
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