參數(shù)資料
型號: M37542F8VGP
元件分類: 微控制器/微處理器
英文描述: 8-BIT, FLASH, 8 MHz, MICROCONTROLLER, PQFP32
封裝: 7 X 7 MM, 0.80 MM PITCH, PLASTIC, LQFP-32
文件頁數(shù): 97/139頁
文件大?。?/td> 1448K
代理商: M37542F8VGP
7542 Group
Rev.3.02
Oct 31, 2006
Page 60 of 134
REJ03B0006-0302
Fig. 74 External circuit of ceramic resonator
Fig. 75 External circuit of RC oscillation
Fig. 76 External clock input circuit
Fig. 73 Processing of XIN and XOUT pins at on-chip oscillator
operation
Clock Generating Circuit
An oscillation circuit can be formed by connecting a resonator be-
tween XIN and XOUT, and an RC oscillation circuit can be formed
by connecting a resistor and a capacitor.
Use the circuit constants in accordance with the resonator
manufacturer's recommended values.
No external resistor is needed between XIN and XOUT since a
feed-back resistor exists on-chip. (An external feed-back resistor
may be needed depending on conditions.)
(1) On-chip oscillator operation
When the MCU operates by the on-chip oscillator for the main
clock, connect XIN pin to VCC through a resistor and leave XOUT
pin open.
The clock frequency of the on-chip oscillator depends on the sup-
ply voltage and the operation temperature range.
Be careful that variable frequencies when designing application
products.
(2) Ceramic resonator
When the ceramic resonator is used for the main clock, connect
the ceramic resonator and the external circuit to pins XIN and
XOUT at the shortest distance. A feedback resistor is built in be-
tween pins XIN and XOUT.
(3) RC oscillation
When the RC oscillation is used for the main clock, connect the
XIN pin and XOUT pin to the external circuit of resistor R and the
capacitor C at the shortest distance.
The frequency is affected by a capacitor, a resistor and a micro-
computer.
So, set the constants within the range of the frequency limits.
(4) External clock
When the external signal clock is used for the main clock, connect
the XIN pin to the clock source and leave XOUT pin open.
Select “0” (ceramic oscillation) to oscillation mode selection bit of
CPU mode register (003B16).
Insert a damping resistor if required.
The resistance will vary depending on the oscillator and
the oscillation drive capacity setting.
Use the value recommended by the maker of the oscillator.
Also, if the oscillator manufacturer’s data sheet specifies
that a feedback resistor be added external to the chip
though a feedback resistor exists on-chip, insert a feed-
back resistor between XIN and XOUT following the
instruction.
Note:
Connect the external
circuit of resistor R
and the capacitor C at
the shortest distance.
The frequency is af-
fected by a capacitor,
a resistor and a micro-
computer.
So, set the constants
within the range of the
frequency limits.
Note:
The clock frequency of the
on-chip oscillator depends
on the supply voltage and
the operation temperature
range.
Be careful that variable
frequencies and obtain
the sufficient margin.
Note:
XIN
XOUT
External oscillation
circuit
VCC
VSS
Open
M37542
XIN
XOUT
C
R
M37542
XIN
COUT
CIN
XOUT
M37542
Rd
XIN
XOUT
M37542
Open
R
相關(guān)PDF資料
PDF描述
M37542M2V-XXXGP 8-BIT, MROM, 8 MHz, MICROCONTROLLER, PQFP32
M37542M2V-XXXGP 8-BIT, MROM, 8 MHz, MICROCONTROLLER, PQFP32
M37542M2-XXXSP 8-BIT, MROM, 8 MHz, MICROCONTROLLER, PDIP32
M37542F8SP 8-BIT, FLASH, 8 MHz, MICROCONTROLLER, PDIP32
M37542F8FP 8-BIT, FLASH, 8 MHz, MICROCONTROLLER, PDSO36
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
M37542M2-XXXFP 制造商:RENESAS 制造商全稱:Renesas Technology Corp 功能描述:SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
M37542M2-XXXGP 制造商:RENESAS 制造商全稱:Renesas Technology Corp 功能描述:SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
M37542M2-XXXHP 制造商:RENESAS 制造商全稱:Renesas Technology Corp 功能描述:SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
M37542M2-XXXSP 制造商:RENESAS 制造商全稱:Renesas Technology Corp 功能描述:SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
M37542M4-XXXFP 制造商:RENESAS 制造商全稱:Renesas Technology Corp 功能描述:SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER