Analog Devices ADM709 Datasheet

Power Supply Monitor

a

FEATURES
Precision Supply Voltage Monitor
+5 V, +3.3 V, +3 V Power Supply Monitor
35 mA Quiescent Current
140 ms (min) Power-On Reset Pulse
Low Cost
8-Pin DIP/SO Packages
Upgrade for MAX709

APPLICATIONS
Microprocessor Systems
Computers
Controllers
Intelligent Instruments
Critical mP Monitoring
Automotive Systems
Critical mP Power Monitoring

GENERAL DESCRIPTION

The ADM709 contains a power supply monitor which generates
a system reset during power-up, power-down and brownout
conditions. When V
goes low and holds the µP in reset. On power-up the
output is held low for 140 ms after V
old. The

RESET output remains operational with VCC as low

as 1 V.
Three supply-voltage threshold levels are available suitable for

+5 V, +3.3 V and for +3 V supply monitoring. The actual reset
voltage threshold is given below.

The ADM709 is available in 8-pin DIP and SOIC packages.

falls below the reset threshold, RESET

CC

rises above the thresh-

CC

Table I. Reset Threshold

Suffix Voltage (V)

L 4.65
M 4.40
T 3.08
S 2.93
R 2.63

RESET

with Reset

ADM709

FUNCTIONAL BLOCK DIAGRAM

V

CC

V

TH

Typical Operating Circuit

Reset Temperature Package

Model Threshold Range Option*

ADM709LAN 4.65 V –40°C to +85°C N-8
ADM709LAR 4.65 V –40°C to +85°C SO-8
ADM709MAN 4.40 V –40°C to +85°C N-8
ADM709MAR 4.40 V –40°C to +85°C SO-8
ADM709TAN 3.08 V –40°C to +85°C N-8
ADM709TAR 3.08 V –40°C to +85°C SO-8
ADM709SAN 2.93 V –40°C to +85°C N-8
ADM709SAR 2.93 V –40°C to +85°C SO-8
ADM709RAN 2.63 V –40°C to +85°C N-8
ADM709RAR 2.63 V –40°C to +85°C SO-8

*N = Plastic DIP; SO = SOIC.

ADM709

RESET

GENERATOR

GND

V

CC

ADM709

RESET

GND GND

ORDERING GUIDE

RESET

RESET

V

CC

µP

REV. 0

Information furnished by Analog Devices is believed to be accurate and
reliable. However, no responsibility is assumed by Analog Devices for its
use, nor for any infringements of patents or other rights of third parties
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.

© Analog Devices, Inc., 1995

One Technology Way, P.O. Box 9106, Norwood. MA 02062-9106, U.S.A.
Tel: [phone] Fax: [phone]

ADM709–SPECIFICATIONS

(VCC = Full Operating Range, TA = T

MIN

to T

unless otherwise noted)

MAX

Parameter Min Typ Max Units Test Conditions/Comments

V

Operating Voltage Range 1.0 5.5 V T

CC

1.2 5.5 V T

Supply Current 35 85 µAV

35 110 µAV
65 150 µAV
65 200 µAV

= 0°C to +70°C

A

= –40°C to +85°C

A

< 3.6 V, T

CC

< 3.6 V, T

CC

< 5.5 V, T

CC

< 5.5 V, T

CC

= 0°C to +70°C

A

= –40°C to +85°C

A

= 0°C to +70°C

A

= –40°C to +85°C

A

Reset Threshold 4.5 4.65 4.75 V ADM709L

4.25 4.40 4.50 V ADM709M

3.00 3.08 3.15 V ADM709T

2.85 2.93 3.00 V ADM709S

2.55 2.63 2.70 V ADM709R

V

to RESET Delay 20 µsV

CC

= Reset Threshold max–min

CC

RESET Active Time-Out Period 140 280 380 ms VCC = Reset Threshold max, VCC Rising

RESET Output Voltage 0.3 V ADM709R/S/T, I

Threshold min

0.4 V ADM709L/M, I
Threshold min

0.8 × V

CC

0.3 V I

0.4 V I

V ADM709R/S/T, I

= 50 µA. VCC ≥ 1.0 V

SINK

= 100 µA. VCC ≥ 1.2 V

SINK

Threshold max

V

–1.5 V V ADM709L/M, I

CC

Threshold max

Specifications subject to change without notice.

ABSOLUTE MAXIMUM RATINGS*

(TA = +25°C unless otherwise noted)

VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to +6 V

RESET Output . . . . . . . . . . . . . . . . . . . –0.3 V to VCC + 0.3 V

V

Input Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 mA

CC

RESET Output Current . . . . . . . . . . . . . . . . . . . . . . . . 20 mA

Mnemonic Pin No. Function

NC 1, 4, 5, 6, 8 No Connect Pins.

V

CC

PIN FUNCTION DESCRIPTION

2 +5 V, +3.3 V, +3 V Power Supply

Power Dissipation, N-8 DIP . . . . . . . . . . . . . . . . . . . . 727 mW

θ

Thermal Impedance . . . . . . . . . . . . . . . . . . . . . 135°C/W

JA

Power Dissipation, SO-8 SOIC . . . . . . . . . . . . . . . . . .470 mW

θ

Thermal Impedance . . . . . . . . . . . . . . . . . . . . . 110°C/W

JA

RESET 7 Logic Output. It remains low while

Operating Temperature Range

Industrial ( A Version) . . . . . . . . . . . . . . . . . –40°C to +85°C

Lead Temperature (Soldering, 10 secs) . . . . . . . . . . . . +300°C

GND 3 Ground, 0 V.

Vapor Phase (60 secs) . . . . . . . . . . . . . . . . . . . . . . . . . +215°C

Infrared (15 secs) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +220°C

Storage Temperature Range . . . . . . . . . . . . .–65°C to +150°C

ESD Rating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .>5 kV

*

Stresses above those listed under “Absolute Maximum Ratings” may cause
permanent damage to the device. This is a stress rating only and functional
operation of the device at these or any other conditions above those listed in the
operational sections of this specification is not implied. Exposure to absolute
maximum ratings for extended periods of time may affect device reliability.

PIN CONFIGURATION

1

NC

2

V

GND

NC

ADM709

CC

TOP VIEW

3

(Not to Scale)

4

NC = NO CONNECT

= 1.2 mA. VCC = Reset

SINK

= 3.2 mA. VCC = Reset

SINK

= 500 µA, VCC ≥ Reset

SOURCE

= 800 µA, VCC ≥ Reset

SOURCE

Input.

V

is below the reset threshold

CC

voltage and for 280 ms (typ) after
VCC rises above the threshold.

8

NC

7

RESET

6

NC

5

NC

–2–

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