HD6433802H Datasheet, PDF (103/435 Pages) Hitachi Semiconductor – Single-Chip Microcomputer

2. Connecting a ceramic oscillator
Figure 4.4 shows a typical method of connecting a ceramic oscillator.
OSC ₁
OSC ₂
C₁
R_f
C₂
R _f = 1 MΩ ±20%
Ceramic
Frequency oscillator
4.0 MHz Murata
C₁, C₂
Recommendation
value
30 pF ±10%
Figure 4.4 Typical Connection to Ceramic Oscillator
3. 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 OSC₁ and OSC₂.
To be avoided
Signal A Signal B
C₁
OSC ₁
OSC ₂
C₂
Figure 4.5 Board Design of Oscillator Circuit
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