Low Voltage Supervisory Circuits

with Watchdog in 4-Lead SC70

ADM8616/ADM8617

Rev. B

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FEATURES

Precision 1.8 V to 5 V power supply monitoring

9 RESET threshold options

1.58 V to 4.63 V

4 RESET timeout options

1 ms, 20 ms, 140 ms, 1120 ms

3 watchdog timeout options

6.3 ms, 102 ms, 1.6 sec

RESET output stages

Push-pull active-low (ADM8616)

Open-drain active-low (ADM8617)

Low power consumption (5 μA)

Power supply glitch immunity

Specified over −40°C to +85°C temperature range

4-lead SC70 package

APPLICATIONS

Microprocessor systems

Computers

Controllers

Intelligent instruments

Portable equipment

FUNCTIONAL BLOCK DIAGRAM

ADM8616

GND

WDI

RESET

RESET

GENERATOR

WATCHDOG

DETECTOR

Figure 1.

GENERAL DESCRIPTION

The ADM8616/ADM8617 are supervisory circuits that monitor

power supply voltage levels and code execution integrity in

microprocessor-based systems. A power-on reset signal is

generated when the supply voltage rises to a preset threshold

level. The ADM8616/ADM8617 have an on-chip watchdog

timer that can reset the microprocessor if it fails to strobe

within a preset timeout period.

Each part is available in the following nine reset threshold

options: 1.58 V, 1.67 V, 2.19 V, 2.32 V, 2.63 V, 2.93 V, 3.08 V,

4.38 V, and 4.63 V. There are four reset timeout options: 1 ms,

20 ms, 140 ms, and 1120 ms. There are also three possible

watchdog timeouts available: 6.3 ms, 102 ms, and 1.6 sec.

The parts differ in terms of reset output configuration. The

ADM8616 is active-low with a push-pull output, while the

ADM8617 is active-low with an open-drain output.

The ADM8616/ADM8617 are available in 4-lead SC70 packages

and typically consume only 5 μA, making them suitable for use

in low power, portable applications.