SH7050 Datasheet, PDF (78/841 Pages) Renesas Technology Corp – 32-Bit RISC Microcomputer SuperH RISC engine Family/

Section 4 Clock Pulse Generator (CPG)
4.4 Notes on Using
Notes on Board Design: When connecting a crystal oscillator, observe the following precautions:
• To prevent induction from interfering with correct oscillation, do not route any signal lines
near the oscillator circuitry.
• When designing the board, place the crystal oscillator and its load capacitors as close as
possible to the XTAL and EXTAL pins.
Figures 4.5 show the precautions regarding oscillator block board settings.
Crossing of signal
lines prohibited
C_L1
XTAL
C_L2
EXTAL
Figure 4.5 Cautions for Oscillator Circuit System Board Design
PLL Oscillation Power Supply: Place oscillation stabilization capacitor C1 and resistor R1 close
to the PLL and CAP pin, and ensure that no other signal lines cross this line. Supply the C1
ground from PLLV_SS.
Separate PLLV_CC and PLLV_SS from the other V_CC and V_SS lines at the board power supply source,
and be sure to insert bypass capacitors C_PB and C_B close to the pins.
Rev. 5.00 Jan 06, 2006 page 58 of 818
REJ09B0273-0500