mc68hc912dg128 Freescale Semiconductor, Inc, mc68hc912dg128 Datasheet - Page 43

• Manufacturer Part Number: mc68hc912dg128
• Description: M68hc12 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

MC68HC912DG128 — Rev 3.0
MOTOROLA
NOTE:
NOTE:
The internal return path for the oscillator is the VSSPLL pin. Therefore it
is recommended to connect the common node of the resonator and the
capacitor directly to the VSSPLL pin.
When selecting a crystal, it is recommended to use one with the lowest
possible frequency in order to minimise EMC emissions.
XTAL is the crystal output.The XTAL pin must be left unterminated when
an external CMOS compatible clock input is connected to the EXTAL
pin. The XTAL output is normally intended to drive only a crystal. The
XTAL output can be buffered with a high-impedance buffer to drive the
EXTAL input of another device.
In all cases take extra care in the circuit board layout around the
oscillator pins. Load capacitances in the oscillator circuits include all
stray layout capacitances. Refer to
diagrams of oscillator circuits.
Freescale Semiconductor, Inc.
For More Information On This Product,
Pinout and Signal Descriptions
Figure 3-5. External Oscillator Connections
Go to: www.freescale.com
Figure 3-4. Common Crystal Connections
MCU
EXTAL
XTAL
MCU
EXTAL
XTAL
NC
2 x E crystal or ceramic resonator
Figure 3-4
C1
EXTERNAL OSCILLATOR
C2
CMOS-COMPATIBLE
Pinout and Signal Descriptions
and
2 x E
Figure 3-5
Signal Descriptions
Technical Data
for
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