HD6433044 Datasheet, PDF (644/867 Pages) Hitachi Semiconductor – Hitachi Single-Chip Microcomputer

XTAL
C_L
L
Rs
EXTAL
C₀
AT-cut parallel-resonance type
Figure 19-3 Crystal Resonator Equivalent Circuit
Table 19-2 Crystal Resonator Parameters
Frequency (MHz) 2
4
Rs max (Ω)
500 120
Co (pF)
8
10
12
80
70
60
7 pF max
16
18
50
40
Use a crystal resonator with a frequency equal to the system clock frequency (ø).
Notes 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 19-4.
When the board is designed, the crystal resonator and its load capacitors should be placed as close
as possible to the XTAL and EXTAL pins.
Avoid
C _L2
Signal A
Signal B
H8/3048 Series
XTAL
EXTAL
C _L1
Figure 19-4 Example of Incorrect Board Design
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