PIC18F13K50-E/P MICROCHIP [Microchip Technology], PIC18F13K50-E/P Datasheet - Page 15

• Manufacturer Part Number: PIC18F13K50-E/P
• Manufacturer: MICROCHIP [Microchip Technology]

2.3.1
The Primary External Oscillator can be enabled or dis-
abled via software. To enable software control of the
Primary External Oscillator, the PCLKEN bit of the
CONFIG1H Configuration register must be set. With
the PCLKEN bit set, the Primary External Oscillator is
controlled by the PRI_SD bit of the OSCCON2 register.
The Primary External Oscillator will be enabled when
the PRI_SD bit is set, and disabled when the PRI_SD
bit is clear.
2.3.2
The LP, XT and HS modes support the use of quartz
crystal resonators or ceramic resonators connected to
OSC1 and OSC2 (Figure 2-2). The mode selects a low,
medium or high gain setting of the internal inverter-
amplifier to support various resonator types and speed.
LP Oscillator mode selects the lowest gain setting of the
internal inverter-amplifier. LP mode current consumption
is the least of the three modes. This mode is best suited
to drive resonators with a low drive level specification, for
example, tuning fork type crystals.
XT Oscillator mode selects the intermediate gain
setting of the internal inverter-amplifier. XT mode
current consumption is the medium of the three modes.
This mode is best suited to drive resonators with a
medium drive level specification.
HS Oscillator mode selects the highest gain setting of the
internal inverter-amplifier. HS mode current consumption
is the highest of the three modes. This mode is best
suited for resonators that require a high drive setting.
Figure 2-2 and Figure 2-3 show typical circuits for
quartz crystal and ceramic resonators, respectively.
© 2009 Microchip Technology Inc.
Note:
PRIMARY EXTERNAL OSCILLATOR
SHUT-DOWN
The Primary External Oscillator cannot be
shut down when it is selected as the
System Clock. To shut down the oscillator,
the system clock source must be either the
Secondary Oscillator or the Internal
Oscillator.
LP, XT AND HS OSCILLATOR
MODES
PIC18F1XK50/PIC18LF1XK50
Preliminary
FIGURE 2-2:
Note 1: A series resistor (R
Note 1: Quartz crystal characteristics vary according
C1
C2
2: The value of R
2: Always verify oscillator performance over
3: For oscillator design assistance, reference
quartz crystals with low drive level.
selected (typically between 2 MΩ to 10 MΩ).
• AN826, “Crystal Oscillator Basics and
• AN849, “Basic PIC
• AN943, “Practical PIC
• AN949, “Making Your Oscillator Work”
to type, package and manufacturer. The
user should consult the manufacturer data
sheets for specifications and recommended
application.
the V
expected for the application.
the following Microchip Applications Notes:
Crystal Selection for rfPIC
Devices” (DS00826)
(DS00849)
Analysis and Design” (DS00943)
(DS00949)
Quartz
Crystal
R
S
DD
(1)
and temperature range that is
QUARTZ CRYSTAL
OPERATION (LP, XT OR
HS MODE)
F
varies with the Oscillator mode
OSC1/CLKIN
OSC2/CLKOUT
R
S
F
) may be required for
(2)
®
PIC
Oscillator Design”
®
Oscillator
DS41350C-page 13
®
MCU
®
and PIC
Sleep
To Internal
Logic
®