HD6413007F20 Datasheet, PDF (579/798 Pages) Renesas Technology Corp – Hardware Manual Renesas 16-Bit Single-Chip Microcomputer H8 Family/H8/300H Series

XTAL
C_L
L
18. Clock Pulse Generator
Rs
EXTAL
C₀
AT-cut parallel-resonance type
Figure 18.3 Crystal Resonator Equivalent Circuit
Table 18.2 Crystal Resonator Parameters
Frequency (MHz)
Rs max (Ω)
Co (pF)
2
4
8
10
12
16
18
20
500 120 80
70
60
50
40
40
7 pF max
Use a crystal resonator with a frequency equal to the system clock frequency (φ).
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 18.4.
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
H8/3006 and H8/3007
XTAL
EXTAL
C _L1
Figure 18.4 Example of Incorrect Board Design
Rev.5.00 Sep. 12, 2007 Page 549 of 764
REJ09B0396-0500