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Revision 1.04

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AS1916 - AS1918

Datasheet - Pin Assignm ents

4 Pin Assignments

Figure 2. Pin Assignments (Top View)

4.1 Pin Descriptions

Table 2. Pin Descriptions

Pin Number

Pin Name

Description

1

RESETN

Active-Low Reset Output (AS1916, AS1918). The RESETN signal toggles from high to low when VCC, or

MRN is pulled low, or the watchdog triggers a reset. This output signal remains low for the reset timeout period

after all supervised voltages exceed their reset threshold, or MRN goes low to high, or the watchdog triggers a

reset.

RESET

Active-High Reset Output (AS1917). The RESET signal toggles from low to high when VCC, or MRN is pulled

low, or the watchdog triggers a reset. This output signal remains high for the reset timeout period (see tRP on

page 4) after all supervised voltages exceed their reset threshold, or MRN goes low to high, or the watchdog

triggers a reset.

2GND

Ground

3MRN

Active-Low Manual Reset Input. Pulling this pin low asserts a reset. This pin is connected to the internal 50k

Ω

pullup to VCC. This reset remains active as long as MRN is low and for the reset timeout period (see tRP on

page 4) after MRN goes high.

Note:

If the manual reset feature is not used, this pin should be unconnected or connected to VCC.

4WDI

Watchdog Input. If WDI remains high or low for longer than the watchdog timeout period (see tWD on page 5),

the internal watchdog timer period expires and a reset is triggered for the reset timeout period (see tRP on page

4). The internal watchdog timer clears whenever a reset is a asserted or when WDI senses a rising or falling

edge.

Note:

To disable the watchdog feature, this pin must be unconnected or connected to a tri-state buffer output.

WDI must be low or unconnected (tristate) during the reset timeout period tRP, (see Figure 11 on page 8).

5VCC

Supervised Voltage Input. This pin serves as the supervised supply voltage input.

AS1916 - AS1918

2

GND

3

MRN

1

RESETN/RESET

4 WDI

5 VCC