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Table 23-3 Crystal Resonator Parameters
Frequency (MHz) 2
R
max (Ω)
500
S
C
max (pF)
7
0
Note on Board Design: When a crystal resonator is connected, the following points should be
noted:
Other signal lines should be routed away from the oscillator circuit to prevent induction from
interfering with correct oscillation. See figure 23-4.
When designing the board, place the crystal resonator and its load capacitors as close as possible
to the XTAL and EXTAL pins.
L
XTAL
Figure 23-3 Crystal Resonator Equivalent Circuit
4
120
7
Avoid
Signal A Signal B
C
L2
C
L1
Figure 23-4 Example of Incorrect Board Design
C
L
R
s
AT-cut parallel-resonance type
C
0
8
12
80
60
7
7
H8S/2633 Series
XTAL
EXTAL
EXTAL
16
20
50
40
7
7
25
40
7
845
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