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FEATURES

 Halts and restarts an out-of-control

microprocessor

 Holds microprocessor in check during power

transients

 Automatically restarts microprocessor after

power failure

 Monitors pushbutton for external override

 Accurate 5%, 10% or 20% resets for 3.3V

systems and 5% or 10% resets for 5.0V

systems

 Eliminates the need for discrete components

 3.3V 20% tolerance for use with 3.0V

systems

 Pin-compatible with the MAXIM

MAX705/MAX706 in 8-pin DIP, 8-pin SOIC,

and

-SOP

 8-pin DIP, 8-pin SOIC and 8-pin

-SOP

packages

 Industrial temperature range -40

C to +85C

PIN ASSIGNMENT

DS1705 and DS1706_R/S/T

(*DS1706L and DS1706P)

PIN DESCRIPTION

PBRST

- Pushbutton Reset Input

- Power Supply

GND

- Ground

IN

- Input

NMI

- Non-maskable Interrupt

ST

- Strobe Input

RST

- Active Low Reset Output

*RST

- Active High Reset Output

(DS1706P and DS1706L only)

WDS

- Watchdog Status Output

DESCRIPTION

The DS1705/DS1706 3.3- or 5.0-Volt MicroMonitor monitors three vital conditions for a microprocessor:

power supply, software execution, and external override. A precision temperature compensated reference

protection. When the sense input detects an out-of-tolerance condition, a non-maskable interrupt is

generated. As the voltage at the device degrades, an internal power fail signal is generated which forces

DS1705/DS1706

3.3V and 5.0V MicroMonitor

19-5212; Rev 4/10

www.maxim-ic.com

8-Pin

-SOP (118-mil)

See Mech. Drawings Section on website

RST(*RST)

WDS

PBRST

ST

NMI

IN

GND

1

2

3

4

8

7

6

5

8-Pin DIP (300 -mil)

PBRST

GND

IN

WDS

RST

ST

NMI

1

2

3

4

8

7

6

5

8-Pin SOIC (150-mil)

1

2

3

4

8

7

6

5

PBRST

GND

IN

WDS

RST(*RST)

ST

NMI