38C3 datasheet(135/224 Pages) RENESAS

Part #	38C3

Description	8-BIT SINGLE-CHIP MICROCOMPUTER 740 FAMILY / 38000 SERIES

PDF	224 Pages

Scroll/Zoom	100%

Manufacturer	RENESAS [Renesas Technology Corp]

Direct Link	http://www.renesas.com

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135 / 224 page

2-70

38C3 Group User’s Manual

APPLICATION

2.7 Reset circuit

2.7.2 Notes on reset circuit

(1)

Reset input voltage control

Make sure that the reset input voltage is 0.5 V or less for Vcc of 2.5 V (Note).

Perform switch to the high-speed mode when power source voltage is within 4.0 to 5.5 V.

Note: M version of mask ROM version is 2.2 V.

(2)

Countermeasure when RESET signal rise time is long

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

RESET pin and the VSS pin. And 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.

38C3 Datasheet(PDF) 135 Page - Renesas Technology Corp