SH7720 Datasheet, PDF (529/1524 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7700 Series

Avoid crossing
signal lines
CL1
CL2
Section 11 Clock Pulse Generator (CPG)
EXTAL
R
XTAL
This LSI
Note: The values for CL1, CL2, and the damping resistance should be determined after
consultation with the crystal manufacturer.
Figure 11.2 Points for Attention when Using Crystal Resonator
(2) Bypass Capacitors
Insert a laminated ceramic capacitor as a bypass capacitor for each V_SS/V_CC pair. Mount the bypass
capacitors to the power supply pins, and use components with a frequency characteristic suitable
for the operating frequency of the LSI, as well as a suitable capacitance value.
(3) When Using a PLL Oscillator Circuit
Keep the wiring from the PLL V_CC and V_SS connection pattern to the power supply pins short, and
make the pattern width large, to minimize the inductance component.
Connect the EXTAL pin to V_CC or V_SSQ and make the XTAL pin open in clock mode 7.
The analog power supply system of the PLL is sensitive to a noise. Therefore the system
malfunction may occur by the intervention with other power supply. Do not supply the analog
power supply with the same resource as the digital power supply of V_CC and V_CCQ.
Rev. 3.00 Jan. 18, 2008 Page 467 of 1458
REJ09B0033-0300