Datasheet ADM810, ADM809 Datasheet (Analog Devices)

Microprocessor

a

Supervisory Circuit in 3-Pin SOT-23

FEATURES
Superior Upgrade for MAX809/MAX810
Specified Over Temperature
Low Power Consumption (17 mA)
Precision Voltage Monitor: +3 V, +3.3 V, +5 V Options
Reset Assertion Down to 1 V V

CC

140 ms min Power-On Reset

Logic Low RESET Output (ADM809)
Logic High RESET Output (ADM810)

APPLICATIONS
Microprocessor Systems
Computers
Controllers
Intelligent Instruments
Automotive Systems

GENERAL DESCRIPTION

The ADM809/ADM810 supervisory circuits monitor the
power supply voltage in microprocessor systems. They pro­vide a reset output during power-up, power-down and
brownout conditions. On power-up, an internal timer holds
reset asserted for 240 ms. This holds the microprocessor in a
reset state until conditions have stabilized. The RESET
output remains operational with V

as low as 1 V. The

CC

ADM809 provides an active low reset signal (RESET) while
the ADM810 provides an active high signal (RESET) output.

Six reset threshold voltage options are available suitable for
monitoring a variety of supply voltages. Refer to Table I.

The reset comparator features built-in glitch immunity,
making it immune to fast transients on V

CC

.

The ADM809/ADM810 consumes only 17 µA, making it

suitable for low power portable equipment. It is packaged in
a 3-pin SOT-23 package.

ADM809/ADM810

FUNCTIONAL BLOCK DIAGRAM

ADM809/ADM810

V

CC

V

REF

V

CC

V

CC

ADM809

GND GND

Figure 1. Typical Operating Circuit

RESET

GENERATOR

GND

RESET

240ms

RESET

INPUT

V

CC

µP

SYSTEM

RESET

(RESET)

REV. 0

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use, nor for any infringements of patents or other rights of third parties
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Fax: [phone] © Analog Devices, Inc., 1997

ADM809/ADM810–SPECIFICATIONS

WARNING!

ESD SENSITIVE DEVICE

(VCC = Full Operating Range, TA = T
for T/S, 3 V for R Models unless otherwise noted.)

MIN

to T

, VCC typ = 5 V for L/M/J, 3.3 V

MAX

Parameter Min Typ Max Units Test Conditions/Comments

Operating Voltage Range 1.0 5.5 V T

V

CC

1.2 5.5 V T

Supply Current 24 60 µAV

17 50 µAV

100 µAV
100 µAV

= 0°C to +70°C

A

= –40°C to +105°C

A

< 5.5 V, ADM8_L/M, T

CC

< 3.6 V, ADM8_R/S/T, T

CC

< 5.5 V, ADM8_L/M, T

CC

< 3.6 V, ADM8_R/S/T, T

CC

RESET THRESHOLD

Reset Voltage Threshold

ADM8_L 4.56 4.63 4.70 V T
ADM8_L 4.5 4.75 V T
ADM8_L 4.40 4.86 V T
ADM8_M 4.31 4.38 4.45 V T
ADM8_M 4.25 4.5 V T
ADM8_M 4.16 4.56 V T
ADM8_␣ J 3.93 4.00 4.06 V T
ADM8_ J 3.89 4.10 V T
ADM8_ J 3.80 4.20 V T
ADM8_T 3.04 3.08 3.11 V T
ADM8_T 3.00 3.15 V T
ADM8_T 2.92 3.23 V T
ADM8_S 2.89 2.93 2.96 V T
ADM8_S 2.85 3.00 V T
ADM8_S 2.78 3.08 V T
ADM8_R 2.59 2.63 2.66 V T
ADM8_R 2.55 2.70 V T
ADM8_R 2.50 2.76 V T

= +25°C

A

= –40°C to +85°C

A

= +85°C to +105°C

A

= +25°C

A

= –40°C to +85°C

A

= +85°C to +105°C

A

= +25°C

A

= –40°C to +85°C

A

= +85°C to +105°C

A

= +25°C

A

= –40°C to +85°C

A

= +85°C to +105°C

A

= +25°C

A

= –40°C to +85°C

A

= +85°C to +105°C

A

= +25°C

A

= –40°C to +85°C

A

= +85°C to +105°C

A

Reset Threshold Temperature Coefficient 30 ppm/°C

V

to Reset Delay 20 µsV

CC

Reset Active Timeout Period 140 240 560 ms T

100 840 ms T

= VTH to (VTH –100 mV)

CC

= –40°C to +85°C

A

= +85°C to +105°C

A

RESET Output Voltage Low (ADM809) 0.3 V VCC = VTH min, I

RESET Output Voltage High (ADM809) 0.8 V

CC

0.4 V V

0.3 V VCC >1.0 V, I

VV

= VTH min, I

CC

> VTH max, I

CC

SINK

VCC–1.5 V VCC > VTH max, I

RESET Output Voltage Low (ADM810) 0.3 V V

= VTH min, I

CC

0.4 V VCC = VTH min, I

RESET Output Voltage High (ADM810) 0.8 V

CC

V 1.8 V < VCC < VTH min, I

= –40°C to +85°C

A

= –40°C to +85°C

A

= +85°C to +105°C

A

= +85°C to +105°C

A

= 1.2 mA, ADM809R/S/T

SINK

= 3.2 mA, ADM809L/M

SINK

= 50 µA

= 500 µA, ADM809R/S/T

SOURCE

= 800 µA, ADM809L/M

SOURCE

= 1.2 mA, ADM810R/S/T

SINK

= 3.2 mA, ADM810L/M

SINK

= 150 µA

SOURCE

ABSOLUTE MAXIMUM RATINGS*

(T

= +25°C unless otherwise noted)

A

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

RESET, RESET . . . . . . . . . . . . . . . . . . –0.3 V to Vcc + 0.5 V

Input Current

V

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 mA

CC

Output Current

RESET, RESET . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 mA

Rate of Rise, V

. . . . . . . . . . . . . . . . . . . . . . . . . . . . 100 V/µs

CC

Power Dissipation, RT-3 SOT-23 . . . . . . . . . . . . . . . . 320 mW

Derate by 4 mW/°C above +70°C

Thermal Impedance . . . . . . . . . . . . . . . . . . . . . . . 333°C/W

θ

JA

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

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

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

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

*Stresses above those listed under Absolute Maximum Ratings may cause perma-

nent damage to the device. This is a stress rating only; 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.

CAUTION

ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily
accumulate on the human body and test equipment and can discharge without detection.
Although the ADM809/ADM810 features proprietary ESD protection circuitry, permanent damage
may occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD
precautions are recommended to avoid performance degradation or loss of functionality.

–2–

REV. 0

PIN FUNCTION DESCRIPTION

T

Pin Mnemonic Function

ADM809/ADM810

V

V

CC

REF

V

REF

V

REF

V

REF

1 GND 0 V. Ground reference for all signals.

2 RESET (ADM809) Active Low Logic Output. RESET

remains low while V

is below the

CC

reset threshold, and remains low for
240 ms (typ) after V

rises above

CC

the reset threshold

2 RESET (ADM810) Active High Logic Output. RESET

remains high while V

is below the

CC

reset threshold, and remains high for
240 ms (typ) after V

rises above

CC

the reset threshold.

3V

CC

Supply voltage being monitored.

PIN CONFIGURATION

GND

1

ADM809/

RESET, RESET

ADM810

TOP VIEW

(Not to Scale)

2

V

3

CC

RESET, RESE

RESET

t1 = RESET TIME = 240ms TYP.
V

t1 t1

= RESET VOLTAGE THRESHOLD

REF

Figure 2. Power Fail Reset Timing

Table I. Reset Threshold Options

Model Threshold

ADM809LART 4.63 V
ADM809MART 4.38 V
ADM809JART 4.00 V
ADM809TART 3.08 V
ADM809SART 2.93 V
ADM809RART 2.63 V

ADM810LART 4.63 V
ADM810MART 4.38 V
ADM810JART 4.00 V
ADM810TART 3.08 V
ADM810SART 2.93 V
ADM810RART 2.63 V

RESET

ORDERING GUIDE

Reset Temperature Brand

Model* Threshold Range Information Quantity

ADM809LART-REEL 4.63 V –40°C to +105°C 9LXX 10K
ADM809LART-REEL-7 4.63 V –40°C to +105°C 9LXX 3K
ADM809MART-REEL 4.38 V –40°C to +105°C 9MXX 10K
ADM809MART-REEL-7 4.38 V –40°C to +105°C 9MXX 3K
ADM809JART-REEL 4.00 V –40°C to +105°C 9JXX 10K
ADM809JART-REEL-7 4.00 V –40°C to +105°C 9JXX 3K
ADM809TART-REEL 3.08 V –40°C to +105°C 9TXX 10K
ADM809TART-REEL-7 3.08 V –40°C to +105°C 9TXX 3K
ADM809SART-REEL 2.93 V –40°C to +105°C 9SXX 10K
ADM809SART-REEL-7 2.93 V –40°C to +105°C 9SXX 3K
ADM809RART-REEL 2.63 V –40°C to +105°C 9RXX 10K
ADM809RART-REEL-7 2.63 V –40°C to +105°C 9RXX 3K

ADM810LART-REEL 4.63 V –40°C to +105°C ALXX 10K
ADM810LART-REEL-7 4.63 V –40°C to +105°C ALXX 3K
ADM810MART-REEL 4.38 V –40°C to +105°C AMXX 10K
ADM810MART-REEL-7 4.38 V –40°C to +105°C AMXX 3K
ADM810JART-REEL 4.00 V –40°C to +105°C AJXX 10K
ADM810JART-REEL-7 4.00 V –40°C to +105°C AJXX 3K
ADM810TART-REEL 3.08 V –40°C to +105°C ATXX 10K
ADM810TART-REEL-7 3.08 V –40°C to +105°C ATXX 3K
ADM810SART-REEL 2.93 V –40°C to +105°C ASXX 10K
ADM810SART-REEL-7 2.93 V –40°C to +105°C ASXX 3K
ADM810RART-REEL 2.63 V –40°C to +105°C ARXX 10K
ADM810RART-REEL-7 2.63 V –40°C to +105°C ARXX 3K

*Only available in Reels.

REV. 0

–3–

ADM809/ADM810

30

25

20

15

10

5

0

–40 –20

020406080

TEMPERATURE – C

VCC = 5V

VCC = 3V

VCC = 1V

—Typical Performance Characteristics

200
180

160
140
120
100

80
60
40
20

0

85

–40 –20

TEMPERATURE – C

VOD = VTH – V

VOD = 10mV

VOD = 20mV

VOD = 100mV

VOD = 200mV

020406080

CC

85

180
160
140
120
100

80
60
40

20

0

–40 –20 020406080

VOD = VTH – V

VOD = 10mV

VOD = 20mV

VOD = 100mV

VOD = 200mV

TEMPERATURE – C

CC

85

Figure 3. Supply Current vs. Tem­perature (ADM8_L/M/R/S/T) (No Load)

240

239.5
239

238.5
238

237.5
237

236.5
236

235.5
235

–40 –20

020406080

TEMPERATURE – C

85

Figure 6. Power-Down RESET Delay
vs. Temperature ADM8_R

Figure 4. Power-Down RESET Delay
vs. Temperature ADM8_L/M

1.002

1.0015

1.001

1.0005

1.0

0.9995

0.999
–40 –20

0 20406080

TEMPERATURE – C

85

Figure 7. Normalized RESET Voltage
Threshold vs. Temperature

400

350

300

250

200

150

100

ADM8_R/S/T

50

0

1 10 1000100

RESET COMPARATOR OVERDRIVE, V

ADM8_L/M

– V

(mV)

TH

CC

Figure 5. Power-Down RESET Delay
vs. Temperature ADM8_T/S/R

SUPPLY VOLTAGE
5V

PK TO PK

T

1

1

T

2

2.00V

CH1

CH2

RESET OUTPUT
VOLTAGE

ADM809T

ADM809R

2.00V M 200ms

CH1

2.00V

Figure 8. RESET Output Voltage vs.
Supply Voltage

Figure 9. Maximum Transient Dura­tion Without Causing a RESET Pulse
vs. RESET Comparator Overdrive

–4–

REV. 0

ADM809/ADM810

INTERFACING TO OTHER DEVICES

OUTPUT

The ADM809/ADM810 Series is designed to integrate with as
many devices as possible and therefore has a standard output
dependant on V

. This enables the part to be used in both 3 V

CC

and 5 V or any nominal voltage within the minimum and maxi­mum specifications for V

. Because of this design approach,

CC

interfacing this device to other devices is simplified.

ENSURING A VALID RESET OUTPUT DOWN TO V

CC

= 0 V

When VCC falls below 0.8 V, ADM809’s RESET no longer
sinks current. A high impedance CMOS logic input connected
to RESET may, therefore, drift to undetermined logic levels. To

eliminate this problem a 100 kΩ resistor should be connected

from RESET to ground.

V

CC

V

CC

ADM809

RESET

THE BENEFITS OF A VERY ACCURATE RESET
THRESHOLD

In other microprocessor supervisory circuits, tolerances in sup­ply voltages lead to an overall increase in RESET tolerance
levels due to the deterioration of the microprocessor RESET
circuit’s power supply. The possibility of a malfunction during
a power failure is greatly reduced because the ADM809 and
ADM810 series can operate effectively even when there are
large degradations of the supply voltages. Another advantage of
the ADM809 and ADM810 series is its very accurate internal
voltage reference circuit. These benefits combine to produce an
exceptionally reliable Voltage Monitor Circuit.

INTERFACING TO MICROPROCESSORS WITH
MULTIPLE INTERRUPTS

In a number of cases it is necessary to interface many interrupts
from different devices (i.e., thermal, attitude and velocity sen­sors). The ADM809 and ADM810 can easily be integrated into
existing interrupt-handling circuits (Figure 11) or used as a
stand-alone device.

V

CC

PRIORITY ENCODER

74LS147

4 LINE BCD
TO µP

GND

Figure 10. Ensuring a Valid RESET Output Down to
V

= 0 V

CC

V

CC

ADM809

RESET

GND

OTHER SENSING

DEVICES

Figure 11. Interfacing to µPs with Multiple Interrupts

REV. 0

–5–

ADM809/ADM810

OUTLINE DIMENSIONS

Dimensions shown in inches and (mm).

Surface Mount Package

RT-3

0.1200 (3.048)

0.1102 (2.799)

0.0550 (1.397)

0.0470 (1.194)

PIN 1

0.0236 (0.599)

0.0177 (0.450)

0.0040 (0.102)

0.0005 (0.013)
SEATING

PLANE

3

1

0.0807 (2.050)

0.0701 (1.781)

0.0210 (0.533)

0.0146 (0.371)

0.1040 (2.642)

0.0827 (2.101)

2

0.0413 (1.049)

0.0374 (0.950)

0.0440 (1.118)

0.0320 (0.813)

0.0100 (0.254)

0.0050 (0.127)

0.0059 (0.150)

0.0034 (0.086)

0.027 (0.686)
REF

C3047–12–4/97

–6–

PRINTED IN U.S.A.

REV. 0