Datasheet

© 2007 Microchip Technology Inc. DS39599G-page 345
PIC18F2220/2320/4220/4320
TABLE 26-24: A/D CONVERTER CHARACTERISTICS: PIC18F2220/2320/4220/4320 (INDUSTRIAL)
PIC18F2220/2320/4220/4320 (EXTENDED)
PIC18LF2220/2320/4220/4320 (INDUSTRIAL)
Param
No.
Symbol Characteristic Min Typ Max Units Conditions
A01 NR Resolution — — 10 bit ΔVREF ≥ 3.0V
A03 E
IL Integral Linearity Error — — <±1 LSb ΔVREF ≥ 3.0V
A04 EDL Differential Linearity Error — — <±1 LSb ΔVREF ≥ 3.0V
A06 EOFF Offset Error — — <±1 LSb ΔVREF ≥ 3.0V
A07 E
GN Gain Error — — <±1 LSb ΔVREF ≥ 3.0V
A10 — Monotonicity guaranteed
(2)
—
A20 ΔV
REF Reference Voltage Range
(V
REFH – VREFL)
3—AV
DD – AVSS V For 10-bit resolution
A21 V
REFH Reference Voltage High AVSS + 3.0V — AVDD + 0.3V V For 10-bit resolution
A22 V
REFL Reference Voltage Low AVSS – 0.3V — AVDD – 3.0V V For 10-bit resolution
A25 V
AIN Analog Input Voltage VREFL —VREFH V
A28 AVDD Analog Supply Voltage VDD – 0.3 — VDD + 0.3 V Tie to VDD
A29 AVSS Analog Supply Voltage VSS – 0.3 — VSS + 0.3 V Tie to VSS
A30 ZAIN Recommended Impedance of
Analog Voltage Source
——2.5
(4)
kΩ
A40 I
AD A/D Current
from V
DD
PIC18FXX20 — — 180
(5)
μA Average current during
conversion
(1)
PIC18LFXX20 — — 90
(5)
μA
A50 IREF VREF Input Current
(3)
—
—
—
—
±5
(5)
±150
(5)
μA
μA
During VAIN acquisition.
During A/D conversion
cycle.
Note 1: When A/D is off, it will not consume any current other than minor leakage current. The power-down current
spec includes any such leakage from the A/D module.
2: The A/D conversion result never decreases with an increase in the input voltage and has no missing
codes.
3: V
REFH current is from RA3/AN3/VREF+ pin or AVDD, whichever is selected as the VREFH source.
V
REFL current is from RA2/AN2/VREF- pin or AVSS, whichever is selected as the VREFL source.
4: Assume quiet environment. If adjacent pins have high-frequency signals (analog or digital), Z
AIN may need
to be reduced to as low as 1 kΩ to fight crosstalk effects.
5: For guidance only.