HD6433308 Datasheet, PDF (275/349 Pages) Hitachi Semiconductor – Hitachi Single-Chip MicroComputer

Not allowed
CL2
Signal A Signal B
H8/330
XTAL
EXTAL
CL1
Figure 16-4. Notes on Board Design around External Crystal
(2) Input of External Clock Signal
x Circuit Configuration: An external clock signal can be input at the EXTAL pin. The reverse-
phase clock signal should be input at the XTAL pin, as shown in the example in Figure 16-5.
EXTAL
XTAL
74HC04
External clock input
Figure 16-5. External Clock Input (Example)
y External Clock Input
Frequency
Duty factor
Double the system clock (Ø) frequency
45% to 55%
267