h8s-2138 Renesas Electronics Corporation., h8s-2138 Datasheet - Page 726

• Manufacturer Part Number: h8s-2138
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2100 Series
• Manufacturer: Renesas Electronics Corporation.

Section 23 Clock Pulse Generator
23.3
Clock pulses can be supplied by connecting a crystal resonator, or by input of an external clock.
23.3.1
Circuit Configuration: A crystal resonator can be connected as shown in the example in figure
23.2. Select the damping resistance R
crystal should be used.
Table 23.2 Damping Resistance Value
Frequency (MHz)
R
Crystal resonator: Figure 23.3 shows the equivalent circuit of the crystal resonator. Use a crystal
resonator that has the characteristics shown in table 23.3 and the same frequency as the system
clock ( ).
Rev. 4.00 Jun 06, 2006 page 672 of 1004
REJ09B0301-0400
d
( )
Oscillator
Connecting a Crystal Resonator
Figure 23.2 Connection of Crystal Resonator (Example)
XTAL
EXTAL
XTAL
Figure 23.3 Crystal Resonator Equivalent Circuit
2
1k
R
d
L
4
500
d
according to table 23.2. An AT-cut parallel-resonance
C
C
C
C
L
0
L1
L2
8
200
AT-cut parallel-resonance type
R
s
10
0
C
L1
= C
EXTAL
L2
12
0
= 10 to 22pF
16
0
20
0