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AS1925/AS1926

Data Sheet - D e t a i l e d D e s c r i p t i o n

8 Detailed Description

Reset Output

falls below a preset threshold (AS1925/AS1926). The reset remains asserted for a fixed timeout delay (see page 4)

The devices are available with four timeout options: 1.5ms, 30ms, 210ms, and 1.68s.

The AS1925/AS1926 have two reset outputs (RESETN and RESET); RESETN is the inverse of RESET. The AS1925

has an active-high push/pull output and an active-low push/pull output. The AS1926 has an active-high push/pull out-

put and an active-low open-drain output.

Manual Reset Input

The devices feature a manual reset input (MRN). When pin MRN is pulled low, a reset is asserted and the reset

remains asserted as long as MRN is kept low, and for a fixed timeout delay after MRN goes high. MRN is connected to

an internal 20k

Ω pullup resistor, thus this pin can be left open if it is not used.

MRN can be driven with CMOS logic-level or with open-drain/collector outputs.

To create a manual reset circuit, connect a normally open momentary switch from MRN to ground (see Figure 9 on

page 8). External debounce circuitry is not required. If pin MRN is driven via long cables or the device is used in a

noisy environment, a 0.1µF capacitor from MRN to ground will provide additional noise immunity.