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Revision 1.5

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AS1901, AS1902, AS1903

Data Sheet

Interfacing to Microprocessors with Bi-Directional Reset Pins

6 Operation

6.1 Interfacing to Microprocessors with Bi-Directional Reset Pins

The device has an open drain RESETN output, which enables easy interfacing to microprocessors (µP) with bi-direc-

tional reset pins, such as the Motorola 68HC11. The RESETN pin of the microcontroller (µC) can be connected directly

to the µP supervisor's RESETN output with a single pull-up resistor (see Figure 1 on page 1).

6.2 Operating Characteristics

resets.

In the graph Maximum Transient Duration vs. Reset Threshold Overdrive (page 4), the conditions are shown, for which

when a reset signal is generated. As the amplitude of the transient increases, the maximum allowable pulse width

decreases.

Supply Current vs. Tem perature,

VCC=3.3V

0

0.1

0.2

0.3

0.4

0.5

-40

- 20

0

20

40

60

80

Temperature (°C)

Pow er-Dow n Reset Delay

vs. Tem perature, VOD = 10m V

0

50

100

150

200

-40

-20

0

20

40

60

80

Temperature (°C)

Power-Up Reset Timeout

vs. Temperature

0

40

80

120

160

200

-40

-20

0

20

406080

Temperature (°C)

Maximum Transient Duration

vs. Reset Threshold Overdrive

0

100

200

300

400

1

10

100

1000

Reset Threshold Overdrive

Vth-Vcc (mV)