Техническая Спецификация для Microchip Technology MCP2515DM-PTPLS
MCP2515
DS21801G-page 56
2003-2012 Microchip Technology Inc.
FIGURE 8-3:
EXTERNAL SERIES RESONANT CRYSTAL OSCILLATOR CIRCUIT
(1)
TABLE 8-1:
CAPACITOR SELECTION FOR
CERAMIC RESONATORS
CERAMIC RESONATORS
TABLE 8-2:
CAPACITOR SELECTION FOR
CRYSTAL OSCILLATOR
CRYSTAL OSCILLATOR
330 k
74AS04
74AS04
MCP2510
OSC1
To Other
Devices
XTAL
330 k
74AS04
0.1 mF
Note 1: Duty cycle restrictions must be observed (see
).
Typical Capacitor Values Used:
Mode
Freq.
OSC1
OSC2
HS
8.0 MHz
27 pF
27 pF
16.0 MHz
22 pF
22 pF
Capacitor values are for design guidance only:
These capacitors were tested with the resonators
listed below for basic start-up and operation. These
values are not optimized.
listed below for basic start-up and operation. These
values are not optimized.
Different capacitor values may be required to
produce acceptable oscillator operation. The user
should test the performance of the oscillator over the
expected V
produce acceptable oscillator operation. The user
should test the performance of the oscillator over the
expected V
DD
and temperature range for the
application.
See the notes following
for additional
information.
Resonators Used:
4.0 MHz
8.0 MHz
16.0 MHz
Osc
Type
(1)(4)
Crystal
Freq.
Freq.
(2)
Typical Capacitor
Values Tested:
C1
C2
HS
4 MHz
27 pF
27 pF
8 MHz
22 pF
22 pF
20 MHz
15 pF
15 pF
Capacitor values are for design guidance only:
These capacitors were tested with the crystals listed
below for basic start-up and operation. These values
are not optimized.
below for basic start-up and operation. These values
are not optimized.
Different capacitor values may be required to
produce acceptable oscillator operation. The user
should test the performance of the oscillator over the
expected V
produce acceptable oscillator operation. The user
should test the performance of the oscillator over the
expected V
DD
and temperature range for the
application.
See the notes following this Table for additional
information.
information.
Crystals Used
(3)
:
4.0 MHz
8.0 MHz
20.0 MHz
Note 1:
While higher capacitance increases the
stability of the oscillator, it also increases
the start-up time.
stability of the oscillator, it also increases
the start-up time.
2:
Since each resonator/crystal has its own
characteristics, the user should consult
the resonator/crystal manufacturer for
appropriate values of external
components.
characteristics, the user should consult
the resonator/crystal manufacturer for
appropriate values of external
components.
3:
R
S
may be required to avoid overdriving
crystals with low drive level specification.
4:
Always verify oscillator performance over
the V
the V
DD
and temperature range that is
expected for the application.