Datasheet

Section 21 Clock Pulse Generator
Rev. 3.00 Mar 17, 2006 page 818 of 926
REJ09B0283-0300
consultation with the resonator manufacturer. The design must ensure that a voltage exceeding the
maximum rating is not applied to the oscillator pin.
21.5.3 Notes on Board Design
When using the crystal resonator, place the crystal resonator and its load capacitors as close as
possible to the XTAL and EXTAL pins. Other signal lines should be routed away from the
oscillation circuit to prevent induction from interfering with correct oscillation. See figure 21.6.
C
L2
Signal A Signal B
C
L1
This LSI
XTAL
EXTAL
Avoid
Figure 21.6 Note on Board Design for Oscillation Circuit
Figure 21.7 shows the external circuitry recommended for the PLL circuit. Separate PLLVcc and
PLLVss from the other Vcc and Vss lines at the board power supply source, and be sure to insert
bypass capacitors CPB and CB close to the pins.
PLLV
CC
PLLV
SS
V
CC
V
SS
Rp: 200Ω
CPB: 0.1 µF
*
CB: 0.1 µF
*
Note: * CB and CPB are laminated ceramic capacitors.
Figure 21.7 Recommended External Circuitry for PLL Circuit