HD6417021 Hitachi Semiconductor, HD6417021 Datasheet - Page 106

• Manufacturer Part Number: HD6417021
• Description: SuperH RISC engine
• Manufacturer: Hitachi Semiconductor

Table 7.1
Frequency [MHz]
Rd [ ]
Crystal Resonator: Figure 7.3 shows an equivalent circuit of the crystal resonator. Use a crystal
resonator with the characteristics listed in table 7.2.
Table 7.2
Parameter
Rs max [ ]
Co max [pF]
Value to be determined (TBD)
7.2.2
An external clock signal can be input at the EXTAL pin as shown in figure 7.6. The XTAL pin
should be left open. The frequency must be equal to the system clock (CK) frequency. The
specifications for the waveform of the external clock input are given below. Make the external
clock frequency the same as the system clock (CK).
90 HITACHI
External Clock Input
Damping Resistance
Crystal Resonator Parameters
2
500
7
C
Figure 7.2 Connection of the Crystal Resonator (Example)
L1
XTAL
= C
2
1k
Figure 7.3 Crystal Resonator Equivalent Circuit
L2
= IC–22 pF
4
120
7
4
500
L
8
80
7
8
200
Frequency (MHz)
EXTAL
XTAL
C
C
L
0
12
60
7
Rs
12
0
Rd
16
50
7
C
C
EXTAL
16
0
L1
L2
20
40
7
20
0