Hitachi H8/3637 Hardware Manual page 91

Connecting a Ceramic Oscillator: Figure 4.4 shows a typical method of connecting a ceramic
oscillator.
Notes on Board Design: When generating clock pulses by connecting a crystal or ceramic
oscillator, pay careful attention to the following points.
Avoid running signal lines close to the oscillator circuit, since the oscillator may be adversely
affected by induction currents. (See figure 4.5.)
The board should be designed so that the oscillator and load capacitors are located as close as
possible to pins OSC
To be avoided
OSC
1
R
f
OSC
2
Figure 4.4 Typical Connection to Ceramic Oscillator
and OSC .
1 2
C
1
C
2
Figure 4.5 Board Design of Oscillator Circuit
C
1
= 1 MΩ ± 20%
R
f
= 30 pF ± 10%
C
C 1
2
= 30 pF ± 10%
C
2
Ceramic oscillator: Murata
Signal A Signal B
OSC
1
OSC
2
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