
PIC18FXX39
DS30485A-page 286
Preliminary
2002 Microchip Technology Inc.
TABLE 23-22: A/D CONVERSION REQUIREMENTS
Param
No.
Symbol
Characteristic
Min
Max
Units
Conditions
130
TAD
A/D clock period
PIC18FXXXX
1.6
20(4)
sTOSC based
PIC18LFXXXX
2.0
6.0
s
A/D RC mode
131
TCNV
Conversion time
(not including acquisition time) (Note 1)
11
12
TAD
132
TACQ
Acquisition time (Note 2)
5
10
—
s
VREF = VDD = 5.0V
VREF = VDD = 2.5V
135
TSWC
Switching Time from convert
→ sample
—
(Note 3)
Note 1: ADRES register may be read on the following TCY cycle.
2: The time for the holding capacitor to acquire the “New” input voltage, when the new input value has not
changed by more than 1 LSB from the last sampled voltage. The source impedance (RS) on the input channels
is 50
. See
Section 18.0 for more information on acquisition time consideration.
3: On the next Q4 cycle of the device clock.
4: The time of the A/D clock period is dependent on the device frequency and the TAD clock divider.