PIC12CE67 Microchip Technology, PIC12CE67 Datasheet - Page 46

• Manufacturer Part Number: PIC12CE67
• Description: 8-Pin/ 8-Bit CMOS Microcontroller with A/D Converter and EEPROM Data Memory
• Manufacturer: Microchip Technology

PIC12CE67X
9.2
9.2.1
The PIC12CE67X can be operated in seven different
oscillator modes. The user can program three
configuration bits (FOSC2:FOSC0) to select one of
these seven modes:
• LP:
• HS:
• XT:
• INTRC*:
• EXTRC*: External Resistor/Capacitor
*Can be configured to support CLKOUT
9.2.2
In XT, HS or LP modes, a crystal or ceramic resonator
is connected to the GP5/OSC1/CLKIN and GP4/OSC2
pins
PIC12CE67X oscillator design requires the use of a
parallel cut crystal. Use of a series cut crystal may give
a frequency out of the crystal manufacturers
specifications. When in XT, HS or LP modes, the
device can have an external clock source drive the
GP5/OSC1/CLKIN pin (Figure 9-3).
FIGURE 9-2:
FIGURE 9-3:
DS40181B-page 46
Clock from
ext. system
Note 1: See Capacitor Selection tables for
to
2: A series resistor (RS) may be required for
3: RF varies with the crystal chosen
C2
C1
Oscillator Configurations
CRYSTAL OSCILLATOR / CERAMIC
RESONATORS
OSCILLATOR TYPES
(1)
(1)
recommended values of C1 and C2.
AT strip cut crystals.
(approx. value = 10 M ).
establish
Low Power Crystal
High Speed Crystal Resonator
Crystal/Resonator
Internal 4 MHz Oscillator
Open
RS
XTAL
(2)
CRYSTAL OPERATION
(OR CERAMIC RESONATOR)
(XT, HS OR LP OSC
CONFIGURATION)
EXTERNAL CLOCK INPUT
OPERATION (XT, HS OR LP
OSC CONFIGURATION)
OSC2
OSC1
oscillation
OSC2
OSC1
RF
(3)
PIC12CE67X
(Figure 9-2).
PIC12CE67X
To internal
SLEEP
logic
The
Preliminary
TABLE 9-1:
TABLE 9-2:
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 in HS mode as well as XT mode to avoid
overdriving crystals with low drive level specification.
Since each crystal has its own characteristics, the
user should consult the crystal manufacturer for
appropriate values of external components.
Type
Type
Osc
Osc
HS
HS
XT
LP
XT
recommended.
Resonator
Resonator
10.0 MHz
32 kHz
455 kHz
2.0 MHz
4.0 MHz
4.0 MHz
8.0 MHz
100 kHz
200 kHz
100 kHz
200 kHz
455 kHz
10 MHz
1 MHz
2 MHz
4 MHz
4 MHz
8 MHz
Freq
Freq
DD
CAPACITOR SELECTION
FOR CERAMIC RESONATORS
- PIC12CE67X
CAPACITOR SELECTION
FOR CRYSTAL OSCILLATOR
- PIC12CE67X
> 4.5V, C1 = C2
(1)
Cap. Range
Cap.Range
1998 Microchip Technology Inc.
22-100 pF
15-68 pF
15-68 pF
15-68 pF
10-68 pF
10-22 pF
15-30 pF
15-30 pF
15-30 pF
15-30 pF
15-30 pF
15-30 pF
15-30 pF
15-47 pF
15-30 pF
15-30 pF
15-30 pF
15 pF
C1
C1
30 pF is
Cap. Range
Cap. Range
200-300 pF
100-200 pF
22-100 pF
15-100 pF
15-68 pF
15-68 pF
15-68 pF
10-68 pF
10-22 pF
30-47 pF
15-82 pF
15-30 pF
15-30 pF
15-47 pF
15-30 pF
15-30 pF
15-30 pF
15 pF
C2
C2