XC68HC705JJ7 Motorola, XC68HC705JJ7 Datasheet - Page 30

• Manufacturer Part Number: XC68HC705JJ7
• Description: MICROCONTROLLER
• Manufacturer: Motorola

General Description
1.7.1 Crystal Oscillator
1.7.2 Ceramic Resonator Oscillator
Advance Information
30
The circuit in
AT-cut, parallel resonant crystal. The crystal manufacturer’s
recommendations should be followed, as the crystal parameters
determine the external component values required to provide maximum
stability and reliable startup. The load capacitance values used in the
oscillator circuit design should include all stray capacitances. The crystal
and components should be mounted as close as possible to the pins for
startup stabilization and to minimize output distortion. An internal startup
resistor of approximately 2 M can be provided between OSC1 and
OSC2 for the crystal type oscillator by use of the OSCRES bit in the
MOR.
In cost-sensitive applications, a ceramic resonator can be used in place
of the crystal. The circuit in
resonator. The resonator manufacturer’s recommendations should be
followed, as the resonator parameters determine the external
component values required for maximum stability and reliable starting.
The load capacitance values used in the oscillator circuit design should
include all stray capacitances. The ceramic resonator and components
should be mounted as close as possible to the pins for startup
stabilization and to minimize output distortion. An internal startup resistor
Ceramic Resonator
OSC1
(a) Crystal or
Connections
2 M
MCU
OSC2
Figure 1-3
Figure 1-3. EPO Oscillator Connections
General Description
(a) shows a typical oscillator circuit for an
(b) RC Oscillator
Figure 1-3
OSC1
Connections
MCU
MC68HC705JJ7 • MC68HC705JP7 — REV 4
R
OSC2
(a) can be used for a ceramic
OSC1
Source Connection
(c) External Clock
EXTERNAL CLOCK
MCU
UNCONNECTED
OSC2
MOTOROLA