Renesas M3A-HS19 用户手册

Features and Specifications 

2.9 Clock Module 

Rev.1.01  Oct 28, .2008 

2-20

REJ10J1351-0101 

 

 

 

2 

2.9 Clock Module 

 

The clock module on the M3A-HS19 consists of following three blocks; 

• 

A block connecting X1 (oscillator) output to SH7619 EXTAL 

• 

A block connecting X2 (ceramic resonator) to EXTAL and XTAL (Optional) 

• 

A block connecting X3 (oscillator) to CK-PHY 

An on-chip oscillator (15.625 MHz) is connected to the SH7619 MCU to provide an operating clock. Another on-chip 

oscillator (25.000 MHz) is also connected to the MCU to provide clock to physical layer. Bus clock output is connected to 

a SDRAM and expansion connectors via damping resisters respectively.   

Figure 2.9.1 shows the block diagram of clock module. 

 

CLK

Oscillator(X1)

15.625

MHz

SH7619(U1)

EXTAL

XTAL

CKIO

Ceramic 

resonator*(X2)

EXCLK expansion 
connector(J10-36)

：Optional

CLK SDRAM(U3)

R98

R117

CLK

Oscillator(X3)

25.000

MHz

R13

R18

CK-PHY

R14

CSTCE-G15M7

(Murata)

Optional

* : To mount a ceramic resonator,remove the resistance R13 and mount the resistance R14.

 

 

Figure 2.9.1 Clock Module