PIC18C242 MICROCHIP [Microchip Technology], PIC18C242 Datasheet - Page 271

• Manufacturer Part Number: PIC18C242
• Description: High-Performance Microcontrollers with 10-Bit A/D
• Manufacturer: MICROCHIP [Microchip Technology]

FIGURE 21-22: A/D CONVERSION TIMING
TABLE 21-22: A/D CONVERSION REQUIREMENTS
Note 1: ADRES register may be read on the following T
Param
7/99 Microchip Technology Inc.
130
131
132
135
136
No.
Note 1: If the A/D clock source is selected as RC, a time of T
2: See the Section 16.0 for minimum conditions, when input voltage has changed more than 1 LSb.
3: The time for the holding capacitor to acquire the “New” input voltage, when the voltage changes full scale
4: On the next Q4 cycle of the device clock.
5: The time of the A/D clock period is dependent on the device frequency and the T
A/D DATA
SAMPLE
A/D CLK
ADRES
Symbol
after the conversion (AV
50 .
BSF ADCON0, GO
2: This is a minimal RC delay (typically 100 nS), which also disconnects the holding capacitor from the
T
T
T
T
ADIF
T
ACQ
SWC
AMP
CNV
GO
AD
Q4
This allows the SLEEP instruction to be executed.
analog input.
A/D clock period
Conversion time
(not including acquisition time) (Note 1)
Acquisition time (Note 3)
Switching Time from convert
Amplifier settling time (Note 2)
132
Note 2
Characteristic
DD
9
to AV
SS
8
PIC18CXXX
PIC18LCXXX
PIC18CXXX
PIC18LCXXX
, or AV
OLD_DATA
7
sample
Preliminary
SS
to AV
. . .
SAMPLING STOPPED
CY
DD
cycle.
. . .
). The source impedance ( R
130
131
Min
1.6
3.0
2.0
3.0
CY
11
15
10
—
1
is added before the A/D clock starts.
2
Note 4
20
20
Max
6.0
9.0
12
—
—
—
(5)
(5)
1
Units
T
AD
s
s
s
s
s
s
s
0
PIC18CXX2
T
T
A/D RC Mode
A/D RC Mode
-40 C
This may be used if the
“new” input voltage has not
changed by more than 1LSb
(i.e. 5 mV @ 5.12V) from the
last sampled voltage (as
stated on C
OSC
OSC
AD
0 C
S
) on the input channels is
clock divider.
based, V
based, V
NEW_DATA
DONE
Temp
Temp
Conditions
DS39026B-page 271
HOLD
T
REF
REF
CY
125 C
125 C
).
full range
3.0V