HD64F3437TF16 Datasheet, PDF (203/752 Pages) Hitachi Semiconductor – 12 V must not be applied to the S-mask model (single-power-supply specification), as this may permanently damage the device.

External Clock: If external clock input is selected, FRC increments on the rising edge of the
FTCI clock signal. Figure 8.5 shows the increment timing.
The pulse width of the external clock signal must be at least 1.5 system clock (ø) periods. The
counter will not increment correctly if the pulse width is shorter than 1.5 system clock periods.
ø
External
clock
FRC clock
pulse
FRC
N
N+1
Figure 8.5 Increment Timing for External Clock Source
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