mc68hc908gr16 Freescale Semiconductor, Inc, mc68hc908gr16 Datasheet - Page 67

• Manufacturer Part Number: mc68hc908gr16
• 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 a single capacitor, but will degrade stability.
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
C1
SIMOSCEN
Figure
X1
R
B
Figure 4-2. CGM External Connections
4-2.)
MC68HC908GR16 Data Sheet, Rev. 5.0
OSC2
R
C2
S
NOTE
CGMXCLK
R
C
F1
F1
CGMXFC
C
F2
V
SSA
V
C
DDA
BYP
V
DD
I/O Signals
67