D12320VF25IV Datasheet, PDF (948/1304 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

Section 20 Clock Pulse Generator
20.3.2 External Clock Input
Circuit Configuration: An external clock signal can be input as shown in the examples in figure
20.5. If the XTAL pin is left open, make sure that stray capacitance is no more than 10 pF.
In example (b), make sure that the external clock is held high in standby mode.
EXTAL
XTAL
Open
External clock input
(a) XTAL pin left open
EXTAL
XTAL
External clock input
(b) Complementary clock input at XTAL pin
Figure 20.5 External Clock Input (Examples)
External Clock: The external clock signal should have the same frequency as the system clock
(φ).
Table 20.4 and figure 20.6 show the input conditions for the external clock.
Rev.6.00 Sep. 27, 2007 Page 916 of 1268
REJ09B0220-0600