PIC18F1220 MICROCHIP [Microchip Technology], PIC18F1220 Datasheet - Page 269

• Manufacturer Part Number: PIC18F1220
• Description: 18/20/28-Pin High-Performance, Enhanced Flash Microcontrollers with 10-bit A/D and nanoWatt Technology
• Manufacturer: MICROCHIP [Microchip Technology]

FIGURE 22-14:
TABLE 22-14: A/D CONVERSION REQUIREMENTS
 2004 Microchip Technology Inc.
130
131
132
135
136
Note 1:
Param
No.
A/D CLK
Note 1: If the A/D clock source is selected as RC, a time of T
A/D DATA
SAMPLE
2:
3:
4:
5:
ADRES
BSF ADCON0, GO
T
T
T
T
T
Symbol
ADIF
2: This is a minimal RC delay (typically 100 ns), which also disconnects the holding capacitor from the analog input.
AD
CNV
ACQ
SWC
AMP
GO
Q4
ADRES register may be read on the following T
See Section 17.0 “10-Bit Analog-to-Digital Converter (A/D) Module” for minimum conditions when input
voltage has changed more than 1 LSb.
The time for the holding capacitor to acquire the “New” input voltage, when the voltage changes full scale after
the conversion (AV
On the next Q4 cycle of the device clock.
The time of the A/D clock period is dependent on the device frequency and the T
(1)
This allows the SLEEP instruction to be executed.
132
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)
A/D CONVERSION TIMING
DD
(Note 2)
Characteristic
to AV
9
SS
, or AV
8
PIC18F1X20
PIC18LF1X20
PIC18F1X20
PIC18LF1X20
OLD_DATA
SS
7
to AV
Sample
CY
. . .
Sampling Stopped
DD
is added before the A/D clock starts.
). The source impedance (R
CY
. . .
131
130
cycle.
Min
1.6
3.0
2.0
3.0
11
15
10
—
1
2
(Note 4)
PIC18F1220/1320
20
20
Max
6.0
9.0
12
—
—
—
1
(5)
(5)
Units
T
AD
s
s
s
s
s
s
s
S
0
) on the input channels is 50 .
T
T
A/D RC mode
A/D RC mode
-40 C
0 C
This may be used if the
“new” input voltage has not
changed by more than 1 LSb
(i.e., 5 mV @ 5.12V) from the
last sampled voltage (as
stated on C
OSC
OSC
AD
based, V
based, V
clock divider.
NEW_DATA
DONE
Temp
Temp
Conditions
DS39605C-page 267
HOLD
T
CY
+125 C
REF
REF
+125 C
).
full range
3.0V