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AS1904, AS1905, AS1906

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

6.3 Negative-Going VDD Transients

resets.

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

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

decreases.

Supply Current vs. Temperature VCC = 3.3V

0

0.1

0.2

0.3

0.4

0.5

-40

-20

0

2040

6080

Temperature (°C)

P o w e r-D o w n Re s e t De la y

vs . T e m p era tu re V O D = 10m V

0

50

10 0

15 0

20 0

-4 0

-2 0

0

2 0

4 06 08 0

T e mp erature (°C )

Power-Up Reset Timeout

vs. Temperature

0

40

80

120

160

200

-40

-20

0

20406080

Temperature (°C)

Maximum Transient Duration

vs. Reset Threshold Overdrive

0

100

200

300

400

1

10

100

1000

Reset Threshold Overdrive

Vth-Vcc (mV)