HD64F3687GHV Datasheet, PDF (126/566 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

Section 5 Clock Pulse Generator
5.8 Usage Notes
5.8.1 Note on Resonators
Resonator characteristics are closely related to board design and should be carefully evaluated by
the user, referring to the examples shown in this section. Resonator circuit parameters will differ
depending on the resonator element, stray capacitance of the PCB, and other factors. Suitable
values should be determined in consultation with the resonator element manufacturer. Design the
circuit so that the resonator element never receives voltages exceeding its maximum rating.
5.8.2 Notes on Board Design
When using a crystal resonator (ceramic resonator), place the resonator and its load capacitors as
close as possible to pins OSC1 and OSC2. Other signal lines should be routed away from the
oscillator circuit to prevent induction from interfering with correct oscillation (see figure 5.20).
Prohibited
Signal A Signal B
C₁
PC0/OSC1
C₂
PC1/OSC2/CLKOUT
Figure 5.20 Example of Incorrect Board Design
Rev. 3.00 Sep. 10, 2007 Page 92 of 528
REJ09B0216-0300