Datasheet

Section 5 Clock Pulse Generators
Rev.5.00 Nov. 02, 2005 Page 72 of 418
REJ09B0028-0500
5.2 Subclock Generator
Figure 5.7 shows a block diagram of the subclock generator.
Note : Registance is a reference value.
2
8MΩ
1
X
X
Figure 5.7 Block Diagram of Subclock Generator
5.2.1 Connecting 32.768-kHz Crystal Resonator
Clock pulses can be supplied to the subclock divider by connecting a 32.768-kHz crystal
resonator, as shown in figure 5.8. Figure 5.9 shows the equivalent circuit of the 32.768-kHz crystal
resonator.
X
X
C
1
C
2
1
2
C = C = 15 pF (typ.)
12
Figure 5.8 Typical Connection to 32.768-kHz Crystal Resonator
X
1
X
2
L
S
C
S
C
O
C
O
= 1.5 pF (typ.)
R
S
= 14 kΩ (typ.)
f
W
= 32.768 kHz
R
S
Note: Constants are reference values.
Figure 5.9 Equivalent Circuit of 32.768-kHz Crystal Resonator