PIC24HJ12GP201 Datasheet, PDF (79/234 Pages) Microchip Technology – High-Performance, 16-Bit Microcontrollers

PIC24HJ12GP201/202
7.0 OSCILLATOR
CONFIGURATION
Note:
This data sheet summarizes the features
of the PIC24HJ12GP201/202 devices. It is
not intended to be a comprehensive
reference source. To complement the
information in this data sheet, refer to the
“PIC24H Family Reference Manual”.
Please see the Microchip web site
(www.microchip.com) for the latest
PIC24H Family Reference Manual
chapters.
The PIC24HJ12GP201/202 oscillator system provides:
• External and internal oscillator options as clock
sources
• An on-chip PLL to scale the internal operating
frequency to the required system clock frequency
• An internal FRC oscillator that can also be used
with the PLL, thereby allowing full-speed
operation without any external clock generation
hardware
• Clock switching between various clock sources
• Programmable clock postscaler for system power
savings
• A Fail-Safe Clock Monitor (FSCM) that detects
clock failure and takes fail-safe measures
• A Clock Control register (OSCCON)
• Nonvolatile Configuration bits for main oscillator
selection.
A simplified diagram of the oscillator system is shown
in Figure 7-1.
FIGURE 7-1:
PIC24HJ12GP201/202 OSCILLATOR SYSTEM DIAGRAM
OSCO
OSCI
Primary Oscillator
S3
S1
PIC24H
XT, HS, EC
S2
DOZE<2:0>
XTPLL, HSPLL,
PLL⁽¹⁾
ECPLL, FRCPLL
S1/S3
FCY
FRC
Oscillator
÷2
FRCDIVN _S7
FOSC
TUN<5:0>
FRCDIV<2:0>
÷ 16
SOSCO
SOSCI
LPRC
Oscillator
Secondary Oscillator
LPOSCEN
Note 1: See Figure 7-2 for PLL details
FRCDIV16 _S6
FRC _S0
LPRC
S5
SOSC
S4
Clock Fail Clock Switch Reset
S7
NOSC<2:0> FNOSC<2:0>
WDT, PWRT,
FSCM
Timer 1
© 2007 Microchip Technology Inc.
Preliminary
DS70282B-page 77