PIC16CE62X
10.2
Oscillator Configurations
TABLE 10-1: CERAMIC RESONATORS,
PIC16CE62X
10.2.1 OSCILLATOR TYPES
Ranges Tested:
The PIC16CE62X can be operated in four different
oscillator options. The user can program two
configuration bits (FOSC1 and FOSC0) to select one of
these four modes:
Mode
XT
Freq
OSC1
OSC2
455 kHz
2.0 MHz
4.0 MHz
68 - 100 pF
15 - 68 pF
15 - 68 pF
68 - 100 pF
15 - 68 pF
15 - 68 pF
• LP
• XT
• HS
• RC
Low Power Crystal
Crystal/Resonator
HS
8.0 MHz
10 - 68 pF
10 - 22 pF
10 - 68 pF
10 - 22 pF
16.0 MHz
High Speed Crystal/Resonator
Resistor/Capacitor
These values are for design guidance only. See
notes at bottom of page.
10.2.2 CRYSTAL OSCILLATOR / CERAMIC
RESONATORS
Resonators Used:
455 kHz Panasonic EFO-A455K04B ± 0.3%
In XT, LP or HS modes a crystal or ceramic resonator
is connected to the OSC1 and OSC2 pins to establish
oscillation (Figure 10-2). The PIC16CE62X) 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, LP or
HS modes, the device can have an external clock
source to drive the OSC1 pin (Figure 10-3).
2.0 MHz Murata Erie CSA2.00MG
4.0 MHz Murata Erie CSA4.00MG
8.0 MHz Murata Erie CSA8.00MT
16.0 MHz Murata Erie CSA16.00MX
± 0.5%
± 0.5%
± 0.5%
± 0.5%
All resonators used did not have built-in capacitors.
TABLE 10-2: CAPACITOR SELECTION
FOR CRYSTAL OSCILLATOR,
PIC16CE62X
FIGURE 10-2: CRYSTAL OPERATION
(OR CERAMIC RESONATOR)
(HS, XT OR LP OSC
Crystal
Freq
Cap. Range
C1
Cap. Range
C2
Osc Type
CONFIGURATION)
LP
32 kHz
200 kHz
200 kHz
1 MHz
33 pF
15 pF
33 pF
15 pF
OSC1
To internal logic
C1
XT
HS
47-68 pF
15 pF
47-68 pF
15 pF
XTAL
RS
SLEEP
RF
OSC2
4 MHz
15 pF
15 pF
4 MHz
15 pF
15 pF
see Note
C2
PIC16CE62X
8 MHz
15-33 pF
15-33 pF
15-33 pF
15-33 pF
20 MHz
See Table 10-1 and Table 10-2 for recommended
values of C1 and C2.
These values are for design guidance only. See
notes at bottom of page.
Note: A series resistor may be required for
Crystals Used
AT strip cut crystals.
32 kHz
200 kHz
1 MHz
Epson C-001R32.768K-A
STD XTL 200.000KHz
ECS ECS-10-13-1
± 20 PPM
± 20 PPM
± 50 PPM
± 50 PPM
± 30 PPM
± 30 PPM
FIGURE 10-3: EXTERNAL CLOCK INPUT
OPERATION (HS, XT OR LP
4 MHz
ECS ECS-40-20-1
OSC CONFIGURATION)
8 MHz
EPSON CA-301 8.000M-C
EPSON CA-301 20.000M-C
20 MHz
Clock from
ext. system
1.
2.
3.
Recommended values of C1 and C2 are identical to the
ranges tested table.
OSC1
PIC16CE62X
Higher capacitance increases the stability of oscillator but
also increases the start-up time.
OSC2
Open
Since each resonator/crystal has its own characteristics,
the user should consult the resonator/crystal manufac-
turer for appropriate values of external components.
4.
Rs may be required in HS mode as well as XT mode to
avoid overdriving crystals with low drive level specifica-
tion.
1998 Microchip Technology Inc.
Preliminary
DS40182A-page 51
MICROCHIP [ MICROCHIP ]
