SH7080 Datasheet, PDF (141/1644 Pages) Renesas Technology Corp – 32-Bit RISC Microcomputer SuperH™ RISC engine Family

Table 4.7 Crystal Resonator Characteristics
Frequency (MHz)
5
8
Rs Max. (Ω) (Reference values) 120
80
C0 Max. (pF) (Reference values) 7
7
Section 4 Clock Pulse Generator (CPG)
10
12.5
60
50
7
7
4.6.2 External Clock Input Method
Figure 4.4 shows an example of an external clock input connection. In this case, make the external
clock high level to stop it when in software standby mode. During operation, make the external
input clock frequency 5 to 12.5 MHz.
When leaving the XTAL pin open, make sure the parasitic capacitance is less than 10 pF.
Even when inputting an external clock, be sure to wait at least the oscillation stabilization time in
power-on sequence or in releasing software standby mode, in order to ensure the PLL stabilization
time.
EXTAL
XTAL
External clock input
Open state
Figure 4.4 Example of External Clock Connection
Rev. 3.00 May 17, 2007 Page 83 of 1582
REJ09B0181-0300