PIC18F67J11T-I Datasheet, PDF (37/466 Pages) Microchip Technology – 64/80-Pin, High-Performance, 1-Mbit Flash Microcontrollers

PIC18F87J11 FAMILY
3.0 OSCILLATOR
CONFIGURATIONS
3.1 Oscillator Types
The PIC18F87J11 family of devices can be operated in
eight different oscillator modes:
1. HS
High-Speed Crystal/Resonator
2. HSPLL High-Speed Crystal/Resonator
with Software PLL Control
3. EC
External Clock with FOSC/4 Output
4. ECPLL External Clock with Software PLL
Control
5. INTIO1 Internal Oscillator Block with FOSC/4
Output on RA6 and I/O on RA7
6. INTIO2 Internal Oscillator Block with I/O on
RA6 and RA7
7. INTPLL1 Internal Oscillator Block with
Software
PLL Control, FOSC/4 Output on RA6
and I/O on RA7
8. INTPLL2 Internal Oscillator Block with Software
PLL Control and I/O on RA6 and RA7
All of these modes are selected by the user by
programming the FOSC<2:0> Configuration bits.
In addition, PIC18F87J11 family devices can switch
between different clock sources, either under software
control or automatically under certain conditions. This
allows for additional power savings by managing
device clock speed in real time without resetting the
application.
The clock sources for the PIC18F87J11 family of
devices are shown in Figure 3-1.
FIGURE 3-1:
PIC18F87J11 FAMILY CLOCK DIAGRAM
OSC2
OSC1
T1OSO
T1OSI
Primary Oscillator
Sleep
OSCTUNE<6>
Secondary Oscillator
T1OSCEN
Enable
Oscillator
OSCCON<6:4>
Internal
Oscillator
Block
8 MHz
Source
8 MHz
(INTOSC)
INTRC
Source
31 kHz (INTRC)
PIC18F87J11 Family
HS, EC
4 x PLL
HSPLL, ECPLL, INTPLL
T1OSC
Peripherals
OSCCON<6:4>
8 MHz
111
4 MHz
110
2 MHz
101
1 MHz
100
500 kHz
011
250 kHz
010
125 kHz
001
1 31 kHz
000
0
OSCTUNE<7>
Internal Oscillator
CPU
Clock
Control
IDLEN
FOSC<2:0> OSCCON<1:0>
Clock Source Option
for Other Modules
WDT, PWRT, FSCM
and Two-Speed Start-up
 2007-2012 Microchip Technology Inc.
DS39778E-page 37