HD6433044 Datasheet, PDF (645/867 Pages) Hitachi Semiconductor – Hitachi Single-Chip Microcomputer

19.2.2 External Clock Input
Circuit Configuration: An external clock signal can be input as shown in the examples in figure
19-5. If the XTAL pin is left open, the stray capacitance should not exceed 10 pF. If the stray
capacitance at the XTAL pin exceeds 10 pF in configuration a, use configuration b instead and
hold the clock high in standby mode.
EXTAL
XTAL
Open
a. XTAL pin left open
External clock input
EXTAL
XTAL
74HC04
External clock input
b. Complementary clock input at XTAL pin
Figure 19-5 External Clock Input (Examples)
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