7643 datasheet(309/424 Pages) RENESAS

tên linh kiện	7643

Giải thích chi tiết về linh kiện	8-BIT SINGLE-CHIP MICROCOMPUTER

PDF	424 Pages

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nhà sản xuất	RENESAS [Renesas Technology Corp]

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309 / 424 page

Rev.2.00

Aug 28, 2006

page 188 of 202

7643 Group

REJ09B0133-0200

APPLICATION

2.9 Reset

2.9.2 Notes on reset

(1) Connecting capacitor

In case where the RESET signal rise time is long, connect a ceramic capacitor or others across

the RESET pin and the VSS pin. Use a 1000 pF or more capacitor for high frequency use. When

connecting the capacitor, note the following :

• Make the length of the wiring which is connected to a capacitor as short as possible.

• Be sure to verify the operation of application products on the user side.

q Reason

If the several nanosecond or several ten nanosecond impulse noise enters the RESET pin, it

may cause a microcomputer failure.

2.9 Reset

2.9.1 Connection example of reset IC

Figure 2.9.1 shows the system example which switches to the RAM backup mode by detecting a drop

of the system power source voltage with the INT interrupt.

Fig. 2.9.1 RAM backup system

VCC

RESET

INT

VCC1

VCC2

GND

M62009L, M62009P, M62009FP

INT

VSS

System power

source voltage

+5 V

7643 Group

7643 bảng dữ liệu(PDF) 309 Page - Renesas Technology Corp