PIC16C63A Microchip Technology, PIC16C63A Datasheet - Page 82

• Manufacturer Part Number: PIC16C63A
• Description: 28/40-Pin 8-Bit CMOS Microcontrollers
• Manufacturer: Microchip Technology

PIC16C63A/65B/73B/74B
11.2
11.2.1
The PIC16CXXX can be operated in four different oscil-
lator modes. The user can program two configuration
bits (FOSC1 and FOSC0) to select one of these four
modes:
• LP
• XT
• HS
• RC
11.2.2
In XT, LP or HS modes a crystal or ceramic resonator
is connected to the OSC1/CLKIN and OSC2/CLKOUT
pins
PIC16CXXX oscillator design requires the use of a par-
allel cut crystal. Use of a series cut crystal may give a
frequency out of the crystal manufacturers specifica-
tions. When in XT, LP or HS modes, the device can
have an external clock source to drive the OSC1/
CLKIN pin (Figure 11-3).
FIGURE 11-2: CRYSTAL/CERAMIC
FIGURE 11-3: EXTERNAL CLOCK INPUT
DS30605A-page 82
Note1:
Clock from
ext. system
to
2:
3:
C1
C2
Oscillator Configurations
CRYSTAL OSCILLATOR/CERAMIC
RESONATORS
OSCILLATOR TYPES
(1)
(1)
establish
Low Power Crystal
Crystal/Resonator
High Speed Crystal/Resonator
Resistor/Capacitor
See Table 11-1 and Table 11-2 for recom-
mended values of C1 and C2.
A series resistor (RS) may be required for
AT strip cut crystals.
RF varies with the crystal chosen.
XTAL
RS
Open
(2)
RESONATOR OPERATION
(HS, XT OR LP
OSC CONFIGURATION)
OPERATION (HS, XT OR LP
OSC CONFIGURATION)
OSC1
OSC2
oscillation
OSC1
OSC2
RF
(3)
(Figure 11-2). The
PIC16CXXX
SLEEP
PIC16CXXX
To
internal
logic
TABLE 11-1:
TABLE 11-2:
Ranges Tested:
XT
HS
Resonators Used:
455 kHz
2.0 MHz
4.0 MHz
8.0 MHz
16.0 MHz Murata Erie CSA16.00MX
Note 1: Recommended values of C1 and C2 are
Osc Type
Mode
200 kHz
20 MHz
32 kHz
1 MHz
4 MHz
8 MHz
All resonators used did not have built-in capacitors.
HS
LP
XT
2: Higher capacitance increases the stability
3: Since each resonator/crystal has its own
4: Rs may be required in HS mode, as well as
These values are for design guidance only. See
notes at bottom of page.
These values are for design guidance only. See
notes at bottom of page.
identical to the ranges tested (Table 11-1).
of oscillator but also increases the start-up
time.
characteristics, the user should consult the
resonator/crystal manufacturer for appropri-
ate values of external components.
XT mode, to avoid overdriving crystals with
low drive level specification.
455 kHz
2.0 MHz
4.0 MHz
8.0 MHz
16.0 MHz
Panasonic EFO-A455K04B
Murata Erie CSA2.00MG
Murata Erie CSA4.00MG
Murata Erie CSA8.00MT
Epson C-001R32.768K-A
STD XTL 200.000KHz
ECS ECS-10-13-1
ECS ECS-40-20-1
EPSON CA-301 8.000M-C
EPSON CA-301 20.000M-C
200 kHz
200 kHz
Freq
20 MHz
Crystal
32 kHz
1 MHz
4 MHz
4 MHz
8 MHz
Freq
CERAMIC RESONATORS
CAPACITOR SELECTION
FOR CRYSTAL OSCILLATOR
Crystals Used
1998 Microchip Technology Inc.
68 - 100 pF
15 - 68 pF
15 - 68 pF
10 - 68 pF
10 - 22 pF
Cap. Range
15-33 pF
15-33 pF
47-68 pF
OSC1
33 pF
15 pF
15 pF
15 pF
15 pF
C1
68 - 100 pF
15 - 68 pF
15 - 68 pF
10 - 68 pF
10 - 22 pF
Cap. Range
47-68 pF
15-33 pF
15-33 pF
0.3%
0.5%
0.5%
0.5%
0.5%
OSC2
20 PPM
20 PPM
50 PPM
50 PPM
30 PPM
30 PPM
33 pF
15 pF
15 pF
15 pF
15 pF
C2