PIC24FJ256GB106-I Datasheet, PDF (111/328 Pages) Microchip Technology – 64/80/100-Pin, 16-Bit Flash Microcontrollers with USB On-The-Go (OTG)

PIC24FJ256GB110 FAMILY
7.0 OSCILLATOR
CONFIGURATION
Note:
This data sheet summarizes the features
of this group of PIC24F devices. It is not
intended to be a comprehensive reference
source. For more information, refer to the
“PIC24F Family Reference Manual”,
”Section 6. Oscillator” (DS39700).
The oscillator system for PIC24FJ256GB110 family
devices has the following features:
• A total of four external and internal oscillator options
as clock sources, providing 11 different clock modes
• An on-chip USB PLL block to provide a stable 48 MHz
clock for the USB module as well as a range of
frequency options for the system clock
• Software-controllable switching between various
clock sources
• Software-controllable postscaler for selective
clocking of CPU for system power savings
• A Fail-Safe Clock Monitor (FSCM) that detects
clock failure and permits safe application recovery
or shutdown
• A separate and independently configurable system
clock output for synchronizing external hardware
A simplified diagram of the oscillator system is shown
in Figure 7-1.
FIGURE 7-1:
PIC24FJ256GB110 FAMILY CLOCK DIAGRAM
PIC24FJ256GB110 Family
OSCO
OSCI
Primary Oscillator
USB PLL
PLL &
DIV
XT, HS, EC
XTPLL, HSPLL
ECPLL, FRCPLL
PLLDIV<2:0> CPDIV<1:0>
FRC
Oscillator _{8 MHz}
(nominal)
8 MHz
4 MHz
FRCDIV
CLKDIV<10:8>
FRC
48 MHz USB Clock
REFOCON<15:8>
Reference Clock
Generator
REFO
Peripherals
CLKO
SOSCO
SOSCI
LPRC
Oscillator _{31 kHz (nominal)}
Secondary Oscillator
SOSCEN
Enable
Oscillator
LPRC
CPU
SOSC
CLKDIV<14:12>
Clock Control Logic
Fail-Safe
Clock
Monitor
WDT, PWRT
Clock Source Option
for Other Modules
© 2008 Microchip Technology Inc.
Preliminary
DS39897B-page 109