SH7014 Datasheet, PDF (88/754 Pages) Renesas Technology Corp – 32-Bit RISC Microcomputer

4. Clock Pulse Generator (CPG)
4.2 Oscillator
Clock pulses can be supplied from a connected crystal resonator or an external clock.
4.2.1 Connecting a Crystal Oscillator
Circuit Configuration: A crystal oscillator can be connected as shown in figure 4.2. Use the
damping resistance (Rd) listed in table 4.1. Use a 4 to 10 MHz crystal oscillator (consult your
dealer concerning the compatibility of the crystal oscillator and the LSI).
C_L1
EXTAL
4 to 10 MHz
C_L2
XTAL
R_d
C_L1 = C_L2 = 18 to 22 pF (Recommended value)
Figure 4.2 Connection of the Crystal Oscillator (Example)
Table 4.1 Damping Resistance Values (Recommended Values)
Parameter
Rd (Ω)
Frequency (MHz)
4
8
10
500
200
0
Crystal Oscillator: Figure 4.3 shows an equivalent circuit of the crystal oscillator. Use a crystal
oscillator with the characteristics listed in table 4.2.
EXTAL
L
C_L
Rs
Co
XTAL
Figure 4.3 Crystal Oscillator Equivalent Circuit
Rev.5.00 Sep. 27, 2007 Page 54 of 716
REJ09B0398-0500