External Clock Input - Hitachi F-ZTAT H8/3039 Series Hardware Manual

16.2.2 External Clock Input

Circuit Configuration: An external clock signal can be input as shown in the examples in figure
16-5. In example b, the clock should be held high in standby mode.
If the XTAL pin is left open, the stray capacitance should not exceed 10 pF.
EXTAL
XTAL
EXTAL
XTAL
a. XTAL pin left open
74HC04
b. Complementary clock input at XTAL pin
Figure 16-5 External Clock Input (Examples)
Open
External clock input
External clock input
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