Low-Voltage Manual Reset & Watchdog
Supervisory Circuits in 4-Lead SC70
Preliminary Technical Data
ADM8611/ADM8616/ADM8617/ADM8618
Rev. PrB
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FEATURES
Precision 1.8V to 5V Power Supply Monitoring
9 Reset Threshold Options:
1.58V to 4.63V
140ms (Min) Reset Timeout
Manual Reset Input (ADM8611)
Watchdog Timer (ADM8616–ADM8618)
Reset Output Stages
Push-Pull Active-Low
Open-Drain Active-Low
Push-Pull Active-High
Low Power Consumption (3µA)
Guaranteed Reset Output valid to VCC=1V
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
GENERAL DESCRIPTION
The ADM8611/ADM8616/ADM8617/ADM8618 are
supervisory circuits which 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 ADM8611’s debounced
manual reset input can be used to initiate a reset by means of an
external push-button or logic signal. The ADM8616–ADM8618
have an on-chip watchdog timer which can reset the
microprocessor if it fails to strobe within a preset timeout
period.
FUNCTIONAL BLOCK DIAGRAMS
RESET
GENERATOR
GND
RESET
V
CC
V
REF
V
CC
ADM8616
WATCHDOG
DETECTOR
WDI
Figure 1.
Each part is available in a choice of the following 9 reset
threshold options: 1.58V, 1.67V, 2.19V, 2.32V, 2.63V, 2.93V,
3.08V, 4.38V and 4.63V. The reset timeout periods are 20ms
(min) and 140ms (min) for the ADM8611 and ADM8616–
ADM8618, respectively. The watchdog timeout period is 1.6s
(typ). The parts differ in terms of reset output configuration, as
indicated in table 1.
The ADM8611/ADM8616/ADM8617/ADM8618 are available
in 4-lead SC70 packages and typically consume only 3µA,
making them suitable for use in low power portable
applications.
Table 1. Selection Table
Output Stage
Part No. Manual Reset Watchdog RESET RESET
ADM8611 Yes - Push-Pull
ADM8616 - Yes Push-Pull
ADM8617 - Yes Open-Drain
ADM8618 - Yes Push-Pull
ADM8611/ADM8616/ADM8617/ADM8618 Preliminary Technical Data
Rev. PrB | Page 2 of 7
ADM8611/ADM8616/ADM8617/ADM8618—SPECIFICATIONS
Table 2. VCC=Full Operating Range, TA=TMIN to TMAX, unless otherwise noted
Parameter Min Typ Max Units Test Conditions/Comments
SUPPLY
VCC Operating Voltage Range 1 5.5 V
Supply Current 10 20 µA VCC=5.5V
5 12 µA VCC=3.6V
RESET THRESHOLD VOLTAGE
ADM861_L 4.50 4.63 4.75 V TA=-40°C to +85°C
ADM861_M 4.25 4.38 4.50 V TA=-40°C to +85°C
ADM861_T 3.00 3.08 3.15 V TA=-40°C to +85°C
ADM861_S 2.85 2.93 3.00 V TA=-40°C to +85°C
ADM861_R 2.55 2.63 2.70 V TA=-40°C to +85°C
ADM861_Z 2.25 2.32 2.38 V TA=-40°C to +85°C
ADM861_Y 2.12 2.19 2.25 V TA=-40°C to +85°C
ADM861_W 1.62 1.67 1.71 V TA=-40°C to +85°C
ADM861_V 1.52 1.58 1.62 V TA=-40°C to +85°C
RESET THRESHOLD TEMPERATURE COEFFICIENT 40 ppm/°C
RESET THRESHOLD HYSTERESIS 3 mV
RESET TIMEOUT PERIOD 20 30 40 ms ADM8611
140 200 280 ms ADM8616–ADM8618
VCC TO RESET DELAY 40 µs VCC falling at 1mV/µs
PUSH-PULL OUTPUT (ADM8611, ADM8616, ADM8618)
RESET Output Voltage 0.3 V VCC>=1.0V, ISINK=50µA
0.3 V VCC>=1.2V, ISINK=100µA
0.3 V VCC>=2.7V, ISINK=1.2mA
0.4 V VCC>=4.5V, ISINK=3.2mA
0.8x VCC V VCC>=2.7V, ISOURCE=500µA
V
CC-1.5 V VCC>=4.5V, I SOURCE=800µA
RESET Rise Time 5 25 ns
From 10% to 90% VCC, CL=5pF,
VCC =3.3V
RESET Output Voltage 0.3 V VCC>=2.7V, ISINK=1.2mA
0.4 V VCC>=4.5V, ISINK=3.2mA
0.8x VCC V VCC>=1.8V, ISOURCE=150µA
0.8x VCC V VCC>=2.7V, ISOURCE=500µA
V
CC-1.5 VCC>=4.5V, I SOURCE=800µA
OPEN-DRAIN OUTPUT (ADM8617)
RESET Output Voltage 0.3 V VCC>=1.0V, ISINK=50µA
0.3 V VCC>=1.2V, ISINK=100µA
0.3 V VCC>=2.7V, ISINK=1.2mA
0.4 V VCC>=4.5V, ISINK=3.2mA
Open-Drain Reset Output Leakage Current 1 µA
Preliminary Technical Data ADM8611/ADM8616/ADM8617/ADM8618
Rev. PrB | Page 3 of 7
Parameter Min Typ Max Units Test Conditions/Comments
MANUAL RESET INPUT (ADM8611)
MR Input Threshold 0.3xVCC V
0.7xVCC V
MR Input Pulse Width 1 µs
MR Glitch Rejection 100 ns
MR Pull-up Resistance 25 50 75 k⍀
MR to Reset Delay 200 ns
WATCHDOG INPUT (ADM8616, ADM8617, ADM8618)
Watchdog Timeout Period 4.3 6.3 9.3 ms ADM86___W
71 102 153 ms ADM86___X
1.12 1.6 2.4 s ADM86___Y
17.9 25.6 38.4 s ADM86___Z
WDI Pulse Width 50 ns VIL=0.3xVCC, VIH=0.7xVCC,
WDI Input Threshold 0.3xVCC V
0.7xVCC V
WDI Input Current 120 160 µA VWDI= VCC, time average
-20 -15 µA VWDI=0, time average
ABSOLUTE MAXIMUM RATINGS
Table 3. TA = 25°C unless otherwise noted.
Parameter Rating
VCC -0.3V to +6V
RESET/RESET -0.3V to +6V
Output Current (RESET, RESET) 20mA
Operating Temperature Range -40°C to +85°C
Storage Temperature Range -65°C to +150°C
θJA Thermal Impedance, SC70 146°C/W
Lead Temperature
Soldering (10 sec) 300°C
Vapour Phase (60 sec) 215°C
Infrared (15 sec) 220°C
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 indicated in the operational
section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.
ADM8611/ADM8616/ADM8617/ADM8618 Preliminary Technical Data
Rev. PrB | Page 4 of 7
PIN CONFIGURATIONS AND FUNCTIONAL DESCRIPTIONS
1
ADM861x
RESET/RESET
GND
V
CC
MR/WDI
2
4
3
TOP VIEW
( Not t o Scale)
Table 4. Pin Functional Descriptions
Pin No. Name Description
1 RESET (ADM8616/ADM8617) Active-Low Reset Output, which is asserted whenever VCC is below the reset.threshold, VTH.
Push-Pull Output Stage for ADM8616.
Open-Drain Output Stage for ADM8617.
RESET (ADM8618) Active-High, Push-Pull Reset Output.
2 MR (ADM8611) Manual Reset Input. This is an active-low input which, when forced low for at least 1µs,
generates a reset.
Features a 52k⍀ internal pull-up.
WDI
(ADM8616/ADM8617/ADM8618)
Watchdog Input. Generates a reset if the logic level on the pin remains low or high for the
duration of the watchdog timeout. The timer is cleared if a logic transition occurs on this
pin or if a reset is generated. Leave floating to disable the watchdog timer.
3 GND Ground
4 VCC Power Supply Voltage being Monitored.
ESD 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 this product 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.
Preliminary Technical Data ADM8611/ADM8616/ADM8617/ADM8618
Rev. PrA | Page 5 of 7
OUTLINE DIMENSIONS
0.30
0.15
0.10 MAX
1.00
0.80
SEATING
PLANE
0.18
0.10 0.30
0.10
0.10 COPLANARITY
2
4 3
1
2.20
1.80
PIN 1
0.50 BSC
0.70
0.50
1.35
1.15
2.40
1.80
1.10
0.80
0.65 BSC
PACKAGE OUTLINE CORRESPONDS IN FULL TO EIAJ SC82
EXCEPT FOR WIDTH OF PIN-2 AS SHOWN
Figure 2. 4-Lead Plastic Surface Mount Package [SC70]
(KS-4)
Dimensions shown in millimeters
ADM8611/ADM8616/ADM8617/ADM8618 Preliminary Technical Data
Rev. PrB | Page 6 of 7
ORDERING GUIDE (ADM8611/ADM8616)
Model1 Reset Threshold (V) Temperature Range Quantity Package Type Branding
ADM8611LABKS-RL 4.63 -40°C to +85°C 10k SC70-4 N0F
ADM8611LABKS-RL7 4.63 -40°C to +85°C 3k SC70-4 N0F
ADM8611MABKS-RL 4.38 -40°C to +85°C 10k SC70-4 N0F
ADM8611MABKS-RL7 4.38 -40°C to +85°C 3k SC70-4 N0F
ADM8611TABKS-RL 3.08 -40°C to +85°C 10k SC70-4 N0F
ADM8611TABKS-RL7 3.08 -40°C to +85°C 3k SC70-4 N0F
ADM8611SABKS-RL 2.93 -40°C to +85°C 10k SC70-4 N0F
ADM8611SABKS-RL7 2.93 -40°C to +85°C 3k SC70-4 N0F
ADM8611RABKS-RL 2.63 -40°C to +85°C 10k SC70-4 N0F
ADM8611RABKS-RL7 2.63 -40°C to +85°C 3k SC70-4 N0F
ADM8611ZABKS-RL 2.32 -40°C to +85°C 10k SC70-4 N0F
ADM8611ZABKS-RL7 2.32 -40°C to +85°C 3k SC70-4 N0F
ADM8611YABKS-RL 2.19 -40°C to +85°C 10k SC70-4 N0F
ADM8611YABKS-RL7 2.19 -40°C to +85°C 3k SC70-4 N0F
ADM8611WABKS-RL 1.67 -40°C to +85°C 10k SC70-4 N0F
ADM8611WABKS-RL7 1.67 -40°C to +85°C 3k SC70-4 N0F
ADM8611VABKS-RL 1.58 -40°C to +85°C 10k SC70-4 N0F
ADM8611VABKS-RL7 1.58 -40°C to +85°C 3k SC70-4 N0F
ADM8616LAKS-RL 4.63 -40°C to +85°C 10k SC70-4 N0G
ADM8616LAKS-RL7 4.63 -40°C to +85°C 3k SC70-4 N0G
ADM8616MAKS-RL 4.38 -40°C to +85°C 10k SC70-4 N0G
ADM8616MAKS-RL7 4.38 -40°C to +85°C 3k SC70-4 N0G
ADM8616TAKS-RL 3.08 -40°C to +85°C 10k SC70-4 N0G
ADM8616TAKS-RL7 3.08 -40°C to +85°C 3k SC70-4 N0G
ADM8616SAKS-RL 2.93 -40°C to +85°C 10k SC70-4 N0G
ADM8616SAKS-RL7 2.93 -40°C to +85°C 3k SC70-4 N0G
ADM8616RAKS-RL 2.63 -40°C to +85°C 10k SC70-4 N0G
ADM8616RAKS-RL7 2.63 -40°C to +85°C 3k SC70-4 N0G
ADM8616ZAKS-RL 2.32 -40°C to +85°C 10k SC70-4 N0G
ADM8616ZAKS-RL7 2.32 -40°C to +85°C 3k SC70-4 N0G
ADM8616YAKS-RL 2.19 -40°C to +85°C 10k SC70-4 N0G
ADM8616YAKS-RL7 2.19 -40°C to +85°C 3k SC70-4 N0G
ADM8616WAKS-RL 1.67 -40°C to +85°C 10k SC70-4 N0G
ADM8616WAKS-RL7 1.67 -40°C to +85°C 3k SC70-4 N0G
ADM8616VAKS-RL 1.58 -40°C to +85°C 10k SC70-4 N0G
ADM8616VAKS-RL7 1.58 -40°C to +85°C 3k SC70-4 N0G
Preliminary Technical Data ADM8611/ADM8616/ADM8617/ADM8618
Rev. PrA | Page 7 of 7
ORDERING GUIDE (ADM8617/ADM8618)
1 Entries in bold type are standard models. Contact factory for availability of non-standard models.
Model Reset Threshold (V) Temperature Range Quantity Package Type Branding
ADM8617LACYKS-RL 4.63 -40°C to +85°C 10k SC70-4 N0H
ADM8617LACYKS-RL7 4.63 -40°C to +85°C 3k SC70-4 N0H
ADM8617MACYKS-RL 4.38 -40°C to +85°C 10k SC70-4 N0H
ADM8617MACYKS-RL7 4.38 -40°C to +85°C 3k SC70-4 N0H
ADM8617TACYKS-RL 3.08 -40°C to +85°C 10k SC70-4 N0H
ADM8617TACYKS-RL7 3.08 -40°C to +85°C 3k SC70-4 N0H
ADM8617SACYKS-RL 2.93 -40°C to +85°C 10k SC70-4 N0H
ADM8617SACYKS-RL7 2.93 -40°C to +85°C 3k SC70-4 N0H
ADM8617RACYKS-RL 2.63 -40°C to +85°C 10k SC70-4 N0H
ADM8617RACYKS-RL7 2.63 -40°C to +85°C 3k SC70-4 N0H
ADM8617ZACYKS-RL 2.32 -40°C to +85°C 10k SC70-4 N0H
ADM8617ZACYKS-RL7 2.32 -40°C to +85°C 3k SC70-4 N0H
ADM8617YACYKS-RL 2.19 -40°C to +85°C 10k SC70-4 N0H
ADM8617YACYKS-RL7 2.19 -40°C to +85°C 3k SC70-4 N0H
ADM8617WACYKS-RL 1.67 -40°C to +85°C 10k SC70-4 N0H
ADM8617WACYKS-RL7 1.67 -40°C to +85°C 3k SC70-4 N0H
ADM8617VACYKS-RL 1.58 -40°C to +85°C 10k SC70-4 N0H
ADM8617VACYKS-RL7 1.58 -40°C to +85°C 3k SC70-4 N0H
ADM8618LACYKS-RL 4.63 -40°C to +85°C 10k SC70-4 N0J
ADM8618LACYKS-RL7 4.63 -40°C to +85°C 3k SC70-4 N0J
ADM8618MACYKS-RL 4.38 -40°C to +85°C 10k SC70-4 N0J
ADM8618MACYKS-RL7 4.38 -40°C to +85°C 3k SC70-4 N0J
ADM8618TACYKS-RL 3.08 -40°C to +85°C 10k SC70-4 N0J
ADM8618TACYKS-RL7 3.08 -40°C to +85°C 3k SC70-4 N0J
ADM8618SACYKS-RL 2.93 -40°C to +85°C 10k SC70-4 N0J
ADM8618SACYKS-RL7 2.93 -40°C to +85°C 3k SC70-4 N0J
ADM8618RACYKS-RL 2.63 -40°C to +85°C 10k SC70-4 N0J
ADM8618RACYKS-RL7 2.63 -40°C to +85°C 3k SC70-4 N0J
ADM8618ZACYKS-RL 2.32 -40°C to +85°C 10k SC70-4 N0J
ADM8618ZACYKS-RL7 2.32 -40°C to +85°C 3k SC70-4 N0J
ADM8618YACYKS-RL 2.19 -40°C to +85°C 10k SC70-4 N0J
ADM8618YACYKS-RL7 2.19 -40°C to +85°C 3k SC70-4 N0J
ADM8618WACYKS-RL 1.67 -40°C to +85°C 10k SC70-4 N0J
ADM8618WACYKS-RL7 1.67 -40°C to +85°C 3k SC70-4 N0J
ADM8618VACYKS-RL 1.58 -40°C to +85°C 10k SC70-4 N0J
ADM8618VACYKS-RL7 1.58 -40°C to +85°C 3k SC70-4 N0J
© 2004 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective companies.
Printed in the U.S.A. PR04795-0-3/04(PrA)
