mc68hc908gr8a Freescale Semiconductor, Inc, mc68hc908gr8a Datasheet - Page 63

• Manufacturer Part Number: mc68hc908gr8a
• Description: M68hc08 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

4.4 I/O Signals
The following paragraphs describe the CGM I/O signals.
4.4.1 Crystal Amplifier Input Pin (OSC1)
The OSC1 pin is an input to the crystal oscillator amplifier.
4.4.2 Crystal Amplifier Output Pin (OSC2)
The OSC2 pin is the output of the crystal oscillator inverting amplifier.
4.4.3 External Filter Capacitor Pin (CGMXFC)
The CGMXFC pin is required by the loop filter to filter out phase corrections. An external filter network is
connected to this pin. (See
Freescale Semiconductor
Note: Filter network in box can be replaced with C
To prevent noise problems, the filter network should be placed as close to
the CGMXFC pin as possible, with minimum routing distances and no
routing of other signals across the network.
(FROM CONFIG)
OSCSTOPENB
OSC1
SIMOSCEN
C1
X1
RB
MC68HC908GR8A • MC68HC908GR4A Data Sheet, Rev. 5
Figure
Figure 4-2. CGM External Connections
4-2.)
OSC2
RS
C2
CGMXCLK
F
but will degrade stability.
NOTE
R
C
F1
F1
CGMXFC
C
F2
V
SSA
V
CBYP
0.1 μF
DDA
V
DD
I/O Signals
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