PIC18F2450/4450
TABLE 21-17: A/D CONVERTER CHARACTERISTICS: PIC18F2450/4450 (INDUSTRIAL)
PIC18LF2450/4450 (INDUSTRIAL)
Param
No.
Symbol
Characteristic
Min
Typ
Max
Units
Conditions
A01
A03
A04
A06
A07
A10
A20
NR
Resolution
—
—
—
—
—
—
10
< 1
bit ΔVREF ≥ 3.0V
EIL
Integral Linearity Error
Differential Linearity Error
Offset Error
—
LSb ΔVREF ≥ 3.0V
LSb ΔVREF ≥ 3.0V
LSb ΔVREF ≥ 3.0V
LSb ΔVREF ≥ 3.0V
EDL
EOFF
EGN
—
—
< 1
—
< 1.5
< 1
Gain Error
—
Monotonicity
Guaranteed(1)
—
VSS ≤ VAIN ≤ VREF
ΔVREF Reference Voltage Range
1.8
3
—
—
—
—
V
V
VDD < 3.0V
VDD ≥ 3.0V
(VREFH – VREFL)
A21
A22
A25
A30
VREFH Reference Voltage High
VSS
—
VREFH
VDD – 3.0V
VREFH
V
V
VREFL
VAIN
Reference Voltage Low
Analog Input Voltage
VSS – 0.3V
VREFL
—
—
—
—
V
ZAIN
Recommended Impedance of
Analog Voltage Source
2.5
kΩ
A50
IREF
VREF Input Current(2)
—
—
—
—
5
150
μA During VAIN acquisition.
μA During A/D conversion
cycle.
Note 1: The A/D conversion result never decreases with an increase in the input voltage and has no missing codes.
2: VREFH current is from RA3/AN3/VREF+ pin or VDD, whichever is selected as the VREFH source.
VREFL current is from RA2/AN2/VREF- pin or VSS, whichever is selected as the VREFL source.
FIGURE 21-14:
A/D CONVERSION TIMING
BSF ADCON0, GO
(Note 2)
131
130
Q4
132
A/D CLK
. . .
. . .
9
8
7
2
1
0
A/D DATA
ADRES
NEW_DATA
OLD_DATA
(1)
TCY
ADIF
GO
DONE
SAMPLING STOPPED
SAMPLE
Note 1: If the A/D clock source is selected as RC, a time of TCY is added before the A/D clock starts. This allows the SLEEPinstruction
to be executed.
2: This is a minimal RC delay (typically 100 ns), which also disconnects the holding capacitor from the analog input.
© 2006 Microchip Technology Inc.
Advance Information
DS39760A-page 291