HD64F2145 Datasheet, PDF (656/829 Pages) Renesas Technology Corp – Hitachi 16-Bit Single-Chip Microcomputer

25.9 Usage Notes
25.9.1 Note on Resonator
Since all kinds of characteristics of the resonator are closely related to the board design by the
user, use the example of resonator connection in this document for only reference; be sure to use
an resonator that has been sufficiently evaluated by the user. Consult with the resonator
manufacturer about the resonator circuit ratings which vary depending on the stray capacitances of
the resonator and installation circuit. Make sure the voltage applied to the oscillator pins does not
exceed the maximum rating.
25.9.2 Notes on Board Design
When using a crystal resonator, the crystal resonator and its load capacitors should be placed as
close as possible to the XTAL and EXTAL pins.
Other signal lines should be routed away from the oscillator circuit to prevent inductive
interference with the correct oscillation as shown in figure 25.9.
Avoid
Signal A Signal B
C_L2
This LSI
XTAL
EXTAL
C_L1
Figure 25.9 Note on Board Design of Oscillator Circuit Section
Rev. 2.0, 08/02, page 616 of 788