SH7616 Datasheet, PDF (138/935 Pages) Renesas Technology Corp – 32-Bit RISC Microcomputer SuperH™ RISC engine Family/SH7600 Series

Section 3 Oscillator Circuits and Operating Modes
3.2.3 Connecting a Crystal Resonator
Connecting a Crystal Resonator: Figure 3.2 shows an example of crystal resonator connection.
The values of damping resistance R and load capacitances CL1 and CL2 should be decided after
investigating the components in collaboration with the manufacturer of the crystal oscillator to be
used. The crystal resonator should be an AT-cut parallel-oscillator type. 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 oscillator circuit to prevent induction from
interfering with correct oscillation.
CKPREQ/CKM
High level
CKIO
EXTAL
XTAL
Output or high
impedance
CL1
CL2
R
Notes: 1. The CKIO pin is an output in clock modes 0,1, and 2. In mode 3, it is high impedance.
2. The values for CL1, CL2, and the damping resistance should be determined after
consultation with the crystal resonator manufacturer.
Figure 3.2 Example of Crystal Oscillator Connection
Rev. 2.00 Mar 09, 2006 page 112 of 906
REJ09B0292-0200