Datasheet

Section 5 Clock Pulse Generators
Rev. 1.50 Sep. 18, 2007 Page 85 of 584
REJ09B0240-0150
Table 5.1 Crystal Resonator Parameters
Frequency (MHz) 4 8 10 16 20
R
S
(Max.) 120 Ω 80 Ω 60 Ω 50 Ω 40 Ω
C
0
(Max.) 7 pF
5.5.2 Connecting Ceramic Resonator
Figure 5.12 shows an example of connecting a ceramic resonator.
Capacitances are reference values.
C
1
C
2
OSC1
OSC2
C
1
= 30 pF ±10%
C
2
= 30 pF ±10%
Figure 5.12 Example of Connection to Ceramic Resonator
5.5.3 External Clock Input Method
To use the external clock, input the external clock on pin OSC1 and leave pin OSC2 open. Figure
5.13 shows an example of connection. The duty cycle of the external clock signal must be 45 to
55%.
OSC1
OSC2
External clock input
Open
Figure 5.13 Example of External Clock Input