6

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1999 IMP, Inc.

IMP705/6/7/8, 8

3L

Application Information

IMP70x

GND

RESET

100k

9

705_06.eps

longer pulls down; it becomes indeterminate. To avoid the possi-

bility that stray charges build up and force RESET to the wrong

state, a pull-down resistor should be connected to the RESET pin,

thus draining such charges to ground and holding RESET

low. The resistor value is not critical. A 100k

Ω resistor will pull

RESET to ground without loading it.

Bi-directional Reset Pin Interfacing

The IMP705/6/7/8 can interface with

µP/µC bi-directional reset

pins by connecting a 4.7k

Ω resistor in series with the RESET

output and the

µP/µC bi-directional RESET pin.

Power

Supply

IMP70x

GND

GND

RESET

4.7k

Ω

705_08.eps

Bi-directional I/O Pin

(Example: 68HC11)

BUF

Buffered

RESET

µC or µP

RESET

Input

Figure 3. Bi-directional Reset Pin Interfacing