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AS1923

Datasheet - Application In form atio n

9 Application Information

Reset Output

The AS1923 RESETN output is asserted low when any of the monitored INx voltages drop below its specified reset threshold (above for -5V

option) and remains asserted for the duration of the reset timeout period (120ms minimum) after all inputs have stabilized (Figure 11).

Figure 11. RESETN Output Timing Diagram

The AS1923B output driver is driven by an internal 10µA current source pullup resistor. For most applications there is no need for an external

pullup resistor to interface with other logic supplies.

Note:

An external pullup resistor must not be connected to the AS1923B.

The AS1923A supports an external pullup resistor to any voltage from 0 to +5.5V if interfaced to non-standard logic supply voltages (see Figure

12).

Figure 12. Interfacing to Various Logic Supply Voltages

90%

INx

RESETN

10%

AS1923A

100k

Ω

GND

2

3

RESETN

RESETN

CPU

+5V