PIC18F258 MICROCHIP [Microchip Technology], PIC18F258 Datasheet - Page 19

• Manufacturer Part Number: PIC18F258
• Description: High Performance, 28/40-Pin Enhanced FLASH Microcontrollers with CAN
• Manufacturer: MICROCHIP [Microchip Technology]

2.0
2.1
The PIC18FXX8 can be operated in one of eight Oscil-
lator modes, programmable by three configuration bits
(FOSC2, FOSC1, and FOSC0).
1.
2.
3.
4.
5.
6.
7.
8.
2.2
In XT, LP, HS or HS4 (PLL) 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. An external clock source may also
be connected to the OSC1 pin, as shown in Figure 2-3
and Figure 2-4.
The PIC18FXX8 oscillator design requires the use of a
parallel cut crystal.
 2002 Microchip Technology Inc.
Note:
LP
XT
HS
HS4
RC
RCIO
EC
ECIO
OSCILLATOR
CONFIGURATIONS
Oscillator Types
Crystal Oscillator/Ceramic
Resonators
Use of a series cut crystal may give a fre-
quency out of the crystal manufacturer’s
specifications.
High Speed Crystal/Resonator
Low Power Crystal
Crystal/Resonator
High Speed Crystal/Resonator with
PLL enabled
External Resistor/Capacitor
External Resistor/Capacitor with I/O
pin enabled
External Clock
External Clock with I/O pin enabled
Preliminary
FIGURE 2-1:
TABLE 2-1:
XT
HS
HS+PLL
These values are for design guidance only.
See notes following Table 2-2.
16.0 MHz
Note 1: See Table 2-1 and Table 2-2 for recommended
455 kHz
2.0 MHz
4.0 MHz
8.0 MHz
All resonators used did not have built-in capacitors.
Mode
2: A series resistor (R
3: R
C1
C2
(1)
(1)
values of C1 and C2.
strip cut crystals.
F
Panasonic EFO-A455K04B
Murata Erie CSA16.00MX
varies with the crystal chosen.
16.0 MHz
20.0 MHz
25.0 MHz
10.0 MHz
Murata Erie CSA2.00MG
Murata Erie CSA4.00MG
XTAL
Murata Erie CSA8.00MT
R
455 kHz
2.0 MHz
4.0 MHz
8.0 MHz
4.0 MHz
8.0 MHz
S
Freq
(2)
Resonators Used:
CERAMIC RESONATORS
OSC2
OSC1
Ranges Tested:
CRYSTAL/CERAMIC
RESONATOR OPERATION
(HS, XT OR LP OSC
CONFIGURATION)
PIC18FXX8
68 - 100 pF
15 - 68 pF
15 - 68 pF
10 - 68 pF
10 - 22 pF
10 - 68 pF
S
) may be required for AT
OSC1
R
TBD
TBD
TBD
TBD
F
(3)
PIC18FXX8
DS41159B-page 17
SLEEP
68 - 100 pF
15 - 68 pF
15 - 68 pF
10 - 68 pF
10 - 22 pF
10 - 68 pF
± 0.3%
± 0.5%
± 0.5%
± 0.5%
± 0.5%
OSC2
To
Internal
Logic
TBD
TBD
TBD
TBD