CAT853, CAT859, CAT863, CAT869

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6

Bi−directional Reset Pin Interfacing

The CAT859 and CAT869 can interface with

mP/mC bi−directional reset pins by connecting a 4.7 kW resistor in series with

the CAT859 and CAT869 reset output and the

mP/mC bi−directional reset pin.

CAT8x9

GND

Power

Supply

Buffered

BUF

INPUT

GND

Bi−directional

I/O Pin

(For example:

68HC11)

Figure 9. Bi−directional Reset Pin Interfacing

RESET

4.7 kW

RESET

RESET

mP

CAT853 and CAT863 Open−Drain RESET Application

The CAT853 and CAT863 features an open−drain RESET

output and therefore need a pull−up resistor on the output for

proper operation, as shown on Figure 10. An advantage of

the open−drain output includes the ability to “wire AND”

several outputs together to form an inexpensive logic circuit.

It is also possible to have the pull−up resistor connected to

pin. The value of the pull−up resistor is not critical in most

applications, typical values being between 5 k

W and 10 kW.

CAT8x3

GND

Power

Supply

INPUT

GND

5 kW

Figure 10. Typical CAT8x3 Open−Drain Circuit Configuration

RESET

mP

RESET