Little higher in this PIC

From page 116, section 11.1 of the 16F87x datasheet,

The source impedance (RS) and the internal sampling switch (RSS)
impedance directly affect the time required to charge
the capacitor CHOLD. The sampling switch (RSS)
impedance varies over the device voltage (VDD), see
Figure 11-2. The maximum recommended impedance
for analog sources is 10 kohm. As the impedance
is decreased, the acquisition time may be decreased.
this acquisition must be done before the conversion
can be started.


Hope that helps,

Brendan
----- Original Message -----
From: "Lyle Killough" <lyle@SUREGRIPCONTROLS.COM>
To: <PICLIST@mitvma.mit.edu>
Sent: Tuesday, June 11, 2002 9:33 AM
Subject: Re: [PIC]:strange analog in problem


> . . . Disclaimer . . .  I have never even read the F877 data sheet
>
> Are you maybe having trouble charging the input capacitance of the ADC
> through 50k?  I kind of remember a 5k recommended maximum on the data
> sheets for some of the other PICs with analog inputs.
>
> Lyle

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