MC68HC908AZ60 Datasheet, PDF (140/480 Pages) Motorola, Inc – HCMOS Microcontroller Unit

Clock Generator Module (CGM)
representation of the internal components and may not represent actual
circuitry. The oscillator configuration uses five components:
• Crystal, X₁
• Fixed capacitor, C₁
• Tuning capacitor, C₂ (can also be a fixed capacitor)
• Feedback resistor, R_B
• Series resistor, R_S (optional)
The series resistor (R_S) may not be required for all ranges of operation,
especially with high-frequency crystals. Refer to the crystal
manufacturer’s data for more information.
Figure 3 also shows the external components for the PLL:
• Bypass capacitor, C_BYP
• Filter capacitor, C_F
Routing should be done with great care to minimize signal cross talk and
noise. (See Acquisition/Lock Time Specifications on page 149 for routing
information and more information on the filter capacitor’s value and its
effects on PLL performance).
MC68HC908AZ60 — Rev 2.0
138
Clock Generator Module (CGM)
12-cgm
MOTOROLA