Datasheet

PIC17C7XX
DS30289C-page 182  1998-2013 Microchip Technology Inc.
Figure 16-2 shows the conversion sequence and the
terms that are used. Acquisition time is the time that the
A/D module’s holding capacitor is connected to the
external voltage level. Then, there is the conversion
time of 12 T
AD, which is started when the GO bit is set.
The sum of these two times is the sampling time. There
is a minimum acquisition time to ensure that the holding
capacitor is charged to a level that will give the desired
accuracy for the A/D conversion.
FIGURE 16-2: A/D CONVERSION SEQUENCE
Acquisition Time
A/D Conversion Time
A/D Sample Time
When A/D holding capacitor starts to charge.
After A/D conversion, or when new A/D channel is selected.
When A/D conversion is started
(setting the GO bit).
A/D conversion complete, result is loaded in ADRES register.
Holding capacitor begins acquiring voltage level on selected
channel, ADIF bit is set.