PIC18F2220 MICROCHIP [Microchip Technology], PIC18F2220 Datasheet - Page 21

• Manufacturer Part Number: PIC18F2220
• Description: 28/40/44-Pin High-Performance, Enhanced Flash Microcontrollers with 10-Bit A/D and nanoWatt Technology
• Manufacturer: MICROCHIP [Microchip Technology]

2.0
2.1
The PIC18F2X20 and PIC18F4X20 devices can be
operated in ten different oscillator modes. The user can
program the configuration bits, F
Configuration Register 1H to select one of these ten
modes:
1.
2.
3.
4.
5.
6.
7.
8.
9.
10. ECIO
2.2
In XT, LP, HS or HSPLL Oscillator modes, a crystal or
ceramic resonator is connected to the OSC1 and
OSC2 pins to establish oscillation. Figure 2-1 shows
the pin connections.
The oscillator design requires the use of a parallel cut
crystal.
 2003 Microchip Technology Inc.
Note:
LP
XT
HS
HSPLL
RC
RCIO
INTIO1
INTIO2
EC
OSCILLATOR
CONFIGURATIONS
Oscillator Types
Crystal Oscillator/Ceramic
Resonators
Use of a series cut crystal may give a fre-
quency out of the crystal manufacturers
specifications.
with PLL enabled
F
output on RA6 and I/O on RA7
and RA7
Low-Power Crystal
Crystal/Resonator
High-Speed Crystal/Resonator
High-Speed Crystal/Resonator
External Resistor/Capacitor with
External Resistor/Capacitor with
I/O on RA6
Internal Oscillator with F
Internal Oscillator with I/O on RA6
External Clock with F
External Clock with I/O on RA6
OSC
/4 output on RA6
OSC
OSC
3:F
/4 output
OSC
PIC18F2220/2320/4220/4320
OSC
0, in
/4
FIGURE 2-1:
TABLE 2-1:
Capacitor values are for design guidance only.
These capacitors were tested with the resonators
listed below for basic start-up and operation. These
values are not optimized.
Different capacitor values may be required to produce
acceptable oscillator operation. The user should test
the performance of the oscillator over the expected
V
See the notes on page 20 for additional information.
Note 1:
DD
Mode
HS
XT
and temperature range for the application.
C1
C2
2:
3:
455 kHz
2.0 MHz
(1)
(1)
Typical Capacitor Values Used:
See Table 2-1 and Table 2-2 for initial values
of C1 and C2.
A series resistor (R
strip cut crystals.
R
16.0 MHz
F
455 kHz
2.0 MHz
4.0 MHz
8.0 MHz
XTAL
R
varies with the oscillator mode chosen.
Freq
S
Resonators Used:
(2)
CAPACITOR SELECTION FOR
CERAMIC RESONATORS
OSC2
OSC1
16.0 MHz
CRYSTAL/CERAMIC
RESONATOR OPERATION
(XT, LP, HS OR HSPLL
CONFIGURATION)
S
OSC1
R
56 pF
47 pF
33 pF
27 pF
22 pF
) may be required for AT
F (3)
4.0 MHz
8.0 MHz
DS39599C-page 19
PIC18FXXXX
Sleep
To
OSC2
Internal
Logic
56 pF
47 pF
33 pF
27 pF
22 pF