External Clock Input; Figure 21.4 External Clock Input (Examples); Table 21.2 Crystal Oscillator Characteristics - Renesas H8S/2368 Series Hardware Manual

Table 21.2 Crystal Oscillator Characteristics

Frequency (MHz)
R max (Ω)
S
C max (pF)
0
21.2.2

External Clock Input

An external clock signal can be input as shown in the examples in figure 21.4. If the XTAL pin is
left open, make sure that parasitic capacitance is no more than 10 pF. When the counter clock is
input to the XTAL pin, make sure that the external clock is held high in standby mode.
Table 21.3 shows the input conditions for the external clock. The frequency of an external clock to
be input should be 8 MHz to 25 MHz.
EXTAL
XTAL
EXTAL
XTAL
8 12
80 60
7 7
(a) XTAL pin left open
(b) Counter clock input at XTAL pin

Figure 21.4 External Clock Input (Examples)

16 20
50 40
7 7
External clock input
Open
External clock input
Rev. 2.00, 05/03, page 679 of 820
25
40
7