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SH7280 Datasheet, PDF (108/1726 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperHTM RISC engine family
Section 4 Clock Pulse Generator (CPG)
4.3 Clock Operating Modes
Table 4.2 shows the clock operating modes of this LSI.
Table 4.2 Clock Operating Modes
Clock I/O
Mode Source
Output
PLL Circuit
Input to Divider
1
EXTAL input or
CK*
crystal resonator
On (× 8)
×8
Note: * To output the clock through the CK pin, appropriate settings should be made in the
PFC. For details, refer to section 23, Pin Function Controller (PFC).
The frequency of the external clock input from the EXTAL pin is multiplied by 8 in the PLL
circuit before it is supplied to the on-chip modules in this LSI, which eliminates the need to
generate a high-frequency clock outside the LSI. Since the input clock frequency ranging from 10
MHz to 12.5 MHz can be used, the internal clock (Iφ) frequency ranges from 10 MHz to 100
MHz.
Maximum operating frequencies:
Iφ = 100 MHz, Bφ = 50 MHz, Pφ = 50 MHz, Mφ = 100 MHz, Aφ = 50 MHz
Table 4.3 shows the frequency division ratios that can be specified with FRQCR.
Rev. 1.00 Jun. 26, 2008 Page 78 of 1692
REJ09B0393-0100