PIC12C508A-04/EJW MICROCHIP [Microchip Technology], PIC12C508A-04/EJW Datasheet - Page 36

• Manufacturer Part Number: PIC12C508A-04/EJW
• Description: 8-Pin, 8-Bit CMOS Microcontrollers
• Manufacturer: MICROCHIP [Microchip Technology]

PIC12C5XX
8.2
8.2.1
The PIC12C5XX can be operated in four different
oscillator
configuration bits (FOSC1:FOSC0) to select one of
these four modes:
• LP:
• XT:
• INTRC: Internal 4 MHz Oscillator
• EXTRC: External Resistor/Capacitor
8.2.2
In XT or LP modes, a crystal or ceramic resonator is
connected to the GP5/OSC1/CLKIN and GP4/OSC2
pins
PIC12C5XX oscillator design requires the use of a
parallel cut crystal. Use of a series cut crystal may give
a
specifications. When in XT or LP modes, the device
can have an external clock source drive the GP5/
OSC1/CLKIN pin (Figure 8-3).
FIGURE 8-2:
FIGURE 8-3:
DS40139E-page 36
Clock from
ext. system
Note 1: See Capacitor Selection tables for
frequency out
to
2: A series resistor (RS) may be required for
3: RF approximate value = 10 M .
C2
C1
Oscillator Configurations
CRYSTAL OSCILLATOR / CERAMIC
RESONATORS
OSCILLATOR TYPES
(1)
(1)
recommended values of C1 and C2.
AT strip cut crystals.
modes.
Low Power Crystal
Crystal/Resonator
establish
Open
RS
XTAL
(2)
CRYSTAL OPERATION (OR
CERAMIC RESONATOR) (XT
OR LP OSC
CONFIGURATION)
EXTERNAL CLOCK INPUT
OPERATION (XT OR LP OSC
CONFIGURATION)
OSC1
OSC2
The
of
oscillation
the
user
OSC2
OSC1
crystal manufacturers
RF
(3)
can
PIC12C5XX
(Figure 8-2).
PIC12C5XX
program
To internal
SLEEP
logic
The
two
TABLE 8-1:
TABLE 8-2:
These values are for design guidance only. Since
each resonator has its own characteristics, the user
should consult the resonator manufacturer for
appropriate values of external components.
Note 1: For V
These values are for design guidance only. Rs may
be required to avoid overdriving crystals with low
drive level specification. Since each crystal has its
own characteristics, the user should consult the crys-
tal manufacturer for appropriate values of external
components.
Type
Type
Osc
Osc
XT
LP
XT
recommended.
4.0 MHz
Resonator
Resonator
32 kHz
200 kHz
1 MHz
4 MHz
Freq
Freq
DD
CAPACITOR SELECTION
CAPACITOR SELECTION
FOR CERAMIC RESONATORS
- PIC12C5XX
FOR CRYSTAL OSCILLATOR -
PIC12C5XX
> 4.5V, C1 = C2
(1)
Cap. Range
Cap.Range
1999 Microchip Technology Inc.
47-68 pF
30 pF
15 pF
15 pF
15 pF
C1
C1
30 pF is
Cap. Range
Cap. Range
47-68 pF
30 pF
15 pF
15 pF
15 pF
C2
C2