MC68HC908GP32 Datasheet, PDF (137/410 Pages) Motorola, Inc – M68HC08 Family of 8-bit microcontroller units (MCUs)

Freescale Semiconductor, Inc.
Clock Generator Module (CGMC)
Acquisition/Lock Time Specifications
filter capacitor, filter capacitor leakage, stray impedances on the circuit
board, and even humidity or circuit board contamination.
7.9.3 Choosing a Filter
As described in 7.9.2 Parametric Influences on Reaction Time, the
external filter network is critical to the stability and reaction time of the
PLL. The PLL is also dependent on reference frequency and supply
voltage.
Either of the filter networks in Figure 7-10 is recommended when using
a 32.768kHz reference crystal. Figure 7-10 (a) is used for applications
requiring better stability. Figure 7-10 (b) is used in low-cost applications
where stability is not critical.
CGMXFC
CGMXFC
10 kΩ
0.033 µF
0.01 µF
0.47 µF
V_SSA
(a)
V_SSA
(b)
Figure 7-10. PLL Filter
MC68HC908GP32•MC68HC08GP32 — Rev. 6
MOTOROLA
Clock Generator Module (CGMC)
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Technical Data
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