Renesas SuperH M3A-HS86 - Manual (Page 32)

Functional Overview
2.7 Clock Module
Rev.1.0 Feb 06. 2007 2-14
REJ10J0916-0100
2
2.7 Clock Module
The clock module in the M3A-HS86 consists of the following two blocks:
•
Output from a oscillator connected to EXTAL of the SH7086
•
Ceramic resonator connected to EXTAL and XTAL
The M3A-HS86 has a 10MHz oscillator connected to it as standard specification.
The system clock output (PA15/CK) of SH7086 is connected to an extension connector through the damping
resister. To connect an extension board to an extension connector, we recommend including a clock buffer that
contains a PLL to ensure that the board will be supplied with a stable clock signal.
Figure2.7.1 shows the block diagram of clock module.
CLK
Oscillator
SH7086
EXTAL
XTAL
PA15/CK
Ceramic Oscillator
10MHz
PA15/CK(SDRAM Clock, Extension Connector)
EXCLK
(Extension
Connector)
Not mounted parts
CY2305SC-1H(Cypress)
Clock Buffer
R7
R3
*1： To mount the ceramic oscillator, remove R3.
*2： To mount the clock buffer, remove R7.
*1
*1
*2
*2
Figure2.7.1 Block Diagram of Clock Module