Supervisory Circuits with Watchdog

and Manual Reset in 5-Lead SOT-23

ADM6316/ADM6317/ADM6318/ADM6319/ADM6320/ADM6321/ADM6322

Rev.PrC

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FEATURES

26 reset threshold options:

2.5 V to 5 V in 100 mV increments

4 reset timeout options:

1 ms, 20 ms, 140 ms, and 1120 ms (Min)

4 watchdog timeout options:

6.3 ms, 102 ms, 1600 ms, and 25.6s (Typ)

Manual reset input

Reset output stages:

Push-pull active-low

Open-drain active-low

Push-pull active-high

Low power consumption (3 µA)

Power supply glitch immunity

Specified over industrial temperature range

5-lead SOT-23 package

APPLICATIONS

Microprocessor systems

Computers

Controllers

Intelligent instruments

Portable equipment

FUNCTIONAL BLOCK DIAGRAM

ADM6316

MR

GND

WDI

RESET

RESET

GENERATOR

WATCHDOG

DETECTOR

DEBOUNCE

Figure 1.

GENERAL DESCRIPTION

The ADM6316/ADM6317/ADM6318/ADM6319/ADM6320/

ADM6321/ADM6322 are supervisory circuits which monitor

power supply voltage levels and code execution integrity in

microprocessor-based systems. As well as providing power on

reset signals, an on-chip watchdog timer can reset the

microprocessor if it fails to strobe within a preset timeout

period. A reset signal can also be asserted by means of an

external push-button, through a manual reset input. The seven

parts feature different combinations of watchdog input, manual

reset input and output stage configuration, as shown in Table 1.

Each part is available in a choice of 26 reset threshold options

ranging from 2.5 V to 5 V in 100 mV increments. There are also

four reset timeout options of 1 ms, 20 ms, 140 ms, and 1120 ms

(min) and four watchdog timeout options of 6.3 ms, 102 ms,

1600 ms, and 25.6s (typ).

The ADM6316-ADM6322 are available in 5-lead SOT-23

packages and typically consume only 3 µA, making them

suitable for use in low power portable applications.

Table 1. Selection Table

Output Stage

Part No.

Watchdog

Manual Reset

RESET

RESET

ADM6316

Yes

Yes

Push-Pull

–

ADM6317

Yes

Yes

–

Push-Pull

ADM6318

Yes

–

Push-Pull

Push-Pull

ADM6319

–

Yes

Push-Pull

Push-Pull

ADM6320

Yes

Yes

Open-Drain

–

ADM6321

Yes

-

Open-Drain

Push-Pull

ADM6322

–

Yes

Open-Drain

Push-Pull

PRELIMINARY TECHNICAL DATA