HD6433308 Datasheet, PDF (274/349 Pages) Hitachi Semiconductor – Hitachi Single-Chip MicroComputer

EXTAL
XTAL
CL1
CL2
CL1 = CL2 = 10 to 22pF
Figure 16-2. Connection of Crystal Oscillator (Example)
y Crystal Oscillator: The external crystal should have the characteristics listed in Table 16-1.
Table 16-1. External Crystal Parameters
Frequency (MHz) 2
4
8
12 16
20
Rs max (Ω)
500 120 60
40 30
20
C0 (pF)
7 pF max
XTAL
CL
L
RS
EXTAL
C0
AT-cut parallel resonating crystal
Figure 16-3. Equivalent Circuit of External Crystal
Ž Note on Board Design: When an external crystal is connected, other signal lines should be
kept away from the crystal circuit to prevent induction from interfering with correct oscillation.
See Figure 16-4. The crystal and its load capacitors should be placed as close as possible to the
XTAL and EXTAL pins.
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