SH7040 Datasheet, PDF (120/923 Pages) Renesas Technology Corp – Renesas 32-Bit Single-Chip RISC Microprocessor SuperH RISC engine Family/SH7040 Series(CPU Core SH-2)

C_L1
EXTAL
4–10 MHz
C_L2
XTAL
R_d
C_L1 = C_L2 = 18–22 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
Table 4.2 Crystal Oscillator Parameters
Parameter
Rs max (Ω)
Co max (pF)
Frequency (MHz)
4
8
10
120
80
60
7
7
7
4.2.2 External Clock Input Method
Figure 4.4 shows an example of an external clock input connection. In this case, make the external
clock high level to stop it when in standby mode. During operation, make the external input clock
frequency 4–10 MHz.
82