AD ADM810LART-REEL Microprocessor supervisory circuit in 3-pin sot-23 Datasheet

a
Microprocessor
Supervisory Circuit in 3-Pin SOT-23
ADM809/ADM810
FUNCTIONAL BLOCK DIAGRAM
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 VCC
140 ms min Power-On Reset
Logic Low RESET Output (ADM809)
Logic High RESET Output (ADM810)
ADM809/ADM810
VCC
RESET
GENERATOR
240ms
VREF
RESET
(RESET)
GND
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 VCC as low as 1 V. The
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.
VCC
VCC
ADM809
GND
VCC
RESET
RESET
INPUT
µP
SYSTEM
GND
The reset comparator features built-in glitch immunity,
making it immune to fast transients on VCC.
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.
Figure 1. Typical Operating Circuit
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.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 617/329-4700
World Wide Web Site: http://www.analog.com
Fax: 617/326-8703
© Analog Devices, Inc., 1997
(VCC = Full Operating Range, TA = TMIN to TMAX, VCC typ = 5 V for L/M/J, 3.3 V
ADM809/ADM810–SPECIFICATIONS for T/S, 3 V for R Models unless otherwise noted.)
Parameter
VCC Operating Voltage Range
Min
4.56
4.5
4.40
4.31
4.25
4.16
3.93
3.89
3.80
3.04
3.00
2.92
2.89
2.85
2.78
2.59
2.55
2.50
Reset Threshold Temperature Coefficient
VCC to Reset Delay
Reset Active Timeout Period
140
100
Test Conditions/Comments
24
17
5.5
5.5
60
50
100
100
V
V
µA
µA
µA
µA
TA = 0°C to +70°C
TA = –40°C to +105°C
VCC < 5.5 V, ADM8_L/M, TA = –40°C to +85°C
VCC < 3.6 V, ADM8_R/S/T, TA = –40°C to +85°C
VCC < 5.5 V, ADM8_L/M, TA = +85°C to +105°C
VCC < 3.6 V, ADM8_R/S/T, TA = +85°C to +105°C
4.70
4.75
4.86
4.45
4.5
4.56
4.06
4.10
4.20
3.11
3.15
3.23
2.96
3.00
3.08
2.66
2.70
2.76
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
TA = +25°C
TA = –40°C to +85°C
TA = +85°C to +105°C
TA = +25°C
TA = –40°C to +85°C
TA = +85°C to +105°C
TA = +25°C
TA = –40°C to +85°C
TA = +85°C to +105°C
TA = +25°C
TA = –40°C to +85°C
TA = +85°C to +105°C
TA = +25°C
TA = –40°C to +85°C
TA = +85°C to +105°C
TA = +25°C
TA = –40°C to +85°C
TA = +85°C to +105°C
ppm/°C
µs
VCC = VTH to (VTH –100 mV)
560
840
ms
ms
TA = –40°C to +85°C
TA = +85°C to +105°C
0.3
0.4
0.3
V
V
V
VCC = VTH min, ISINK = 1.2 mA, ADM809R/S/T
VCC = VTH min, ISINK = 3.2 mA, ADM809L/M
VCC >1.0 V, ISINK = 50 µA
V
V
VCC > VTH max, ISOURCE = 500 µA, ADM809R/S/T
VCC > VTH max, ISOURCE = 800 µA, ADM809L/M
V
V
VCC = VTH min, ISINK = 1.2 mA, ADM810R/S/T
VCC = VTH min, ISINK = 3.2 mA, ADM810L/M
V
1.8 V < VCC < VTH min, ISOURCE = 150 µA
4.63
4.38
4.00
3.08
2.93
2.63
240
0.8 VCC
VCC–1.5
RESET Output Voltage Low (ADM810)
RESET Output Voltage High (ADM810)
Units
30
20
RESET Output Voltage Low (ADM809)
RESET Output Voltage High (ADM809)
Max
1.0
1.2
Supply Current
RESET THRESHOLD
Reset Voltage Threshold
ADM8_L
ADM8_L
ADM8_L
ADM8_M
ADM8_M
ADM8_M
ADM8_␣ J
ADM8_ J
ADM8_ J
ADM8_T
ADM8_T
ADM8_T
ADM8_S
ADM8_S
ADM8_S
ADM8_R
ADM8_R
ADM8_R
Typ
0.3
0.4
0.8 VCC
ABSOLUTE MAXIMUM RATINGS*
(TA = +25°C unless otherwise noted)
VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to +6 V
RESET, RESET . . . . . . . . . . . . . . . . . . –0.3 V to Vcc + 0.5 V
Input Current
VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 mA
Output Current
RESET, RESET . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 mA
Rate of Rise, VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100 V/µs
Power Dissipation, RT-3 SOT-23 . . . . . . . . . . . . . . . . 320 mW
Derate by 4 mW/°C above +70°C
θJA Thermal Impedance . . . . . . . . . . . . . . . . . . . . . . . 333°C/W
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 permanent 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–
WARNING!
ESD SENSITIVE DEVICE
REV. 0
ADM809/ADM810
PIN FUNCTION DESCRIPTION
Pin
Mnemonic
Function
1
GND
0 V. Ground reference for all signals.
2
RESET (ADM809) Active Low Logic Output. RESET
remains low while VCC is below the
reset threshold, and remains low for
240 ms (typ) after VCC rises above
the reset threshold
2
3
VREF
VCC
RESET
Table I. Reset Threshold Options
GND 1
RESET, RESET 2
t1
Figure 2. Power Fail Reset Timing
PIN CONFIGURATION
TOP VIEW
(Not to Scale)
VREF
t1 = RESET TIME = 240ms TYP.
VREF = RESET VOLTAGE THRESHOLD
Supply voltage being monitored.
ADM809/
ADM810
VREF
t1
RESET (ADM810) Active High Logic Output. RESET
remains high while VCC is below the
reset threshold, and remains high for
240 ms (typ) after VCC rises above
the reset threshold.
VCC
VREF
3 VCC
RESET, RESET
Model
RESET
Threshold
ADM809LART
ADM809MART
ADM809JART
ADM809TART
ADM809SART
ADM809RART
4.63 V
4.38 V
4.00 V
3.08 V
2.93 V
2.63 V
ADM810LART
ADM810MART
ADM810JART
ADM810TART
ADM810SART
ADM810RART
4.63 V
4.38 V
4.00 V
3.08 V
2.93 V
2.63 V
ORDERING GUIDE
Model*
Reset
Threshold
Temperature
Range
Brand
Information
Quantity
ADM809LART-REEL
ADM809LART-REEL-7
ADM809MART-REEL
ADM809MART-REEL-7
ADM809JART-REEL
ADM809JART-REEL-7
ADM809TART-REEL
ADM809TART-REEL-7
ADM809SART-REEL
ADM809SART-REEL-7
ADM809RART-REEL
ADM809RART-REEL-7
ADM810LART-REEL
ADM810LART-REEL-7
ADM810MART-REEL
ADM810MART-REEL-7
ADM810JART-REEL
ADM810JART-REEL-7
ADM810TART-REEL
ADM810TART-REEL-7
ADM810SART-REEL
ADM810SART-REEL-7
ADM810RART-REEL
ADM810RART-REEL-7
4.63 V
4.63 V
4.38 V
4.38 V
4.00 V
4.00 V
3.08 V
3.08 V
2.93 V
2.93 V
2.63 V
2.63 V
4.63 V
4.63 V
4.38 V
4.38 V
4.00 V
4.00 V
3.08 V
3.08 V
2.93 V
2.93 V
2.63 V
2.63 V
–40°C to +105°C
–40°C to +105°C
–40°C to +105°C
–40°C to +105°C
–40°C to +105°C
–40°C to +105°C
–40°C to +105°C
–40°C to +105°C
–40°C to +105°C
–40°C to +105°C
–40°C to +105°C
–40°C to +105°C
–40°C to +105°C
–40°C to +105°C
–40°C to +105°C
–40°C to +105°C
–40°C to +105°C
–40°C to +105°C
–40°C to +105°C
–40°C to +105°C
–40°C to +105°C
–40°C to +105°C
–40°C to +105°C
–40°C to +105°C
9LXX
9LXX
9MXX
9MXX
9JXX
9JXX
9TXX
9TXX
9SXX
9SXX
9RXX
9RXX
ALXX
ALXX
AMXX
AMXX
AJXX
AJXX
ATXX
ATXX
ASXX
ASXX
ARXX
ARXX
10K
3K
10K
3K
10K
3K
10K
3K
10K
3K
10K
3K
10K
3K
10K
3K
10K
3K
10K
3K
10K
3K
10K
3K
*Only available in Reels.
REV. 0
–3–
ADM809/ADM810—Typical Performance Characteristics
200
30
25
VOD = 10mV
VOD = 10mV
140
140
VCC = 3V
VOD = VTH – VCC
160
160
20
120
120
100
VOD = 20mV
100
15
80
VOD = 20mV
80
10
60
60
VCC = 1V
–20
0
20
40
60
TEMPERATURE – C
40
VOD = 100mV
40
5
0
–40
180
VOD = VTH – VCC
180
VCC = 5V
80 85
Figure 3. Supply Current vs. Temperature (ADM8_L/M/R/S/T) (No Load)
VOD = 100mV
20
20
0
–40
VOD = 200mV
–20
0
20
40
60
TEMPERATURE – C
Figure 4. Power-Down RESET Delay
vs. Temperature ADM8_L/M
VOD = 200mV
0
–40
80 85
–20
0
20
40
60
TEMPERATURE – C
80 85
Figure 5. Power-Down RESET Delay
vs. Temperature ADM8_T/S/R
1.002
240
239.5
SUPPLY VOLTAGE
5VPK TO PK
1.0015
239
238.5
1.001
T
238
1.0005
237.5
RESET OUTPUT
VOLTAGE
1
237
ADM809T
ADM809R
1.0
236.5
236
2
0.9995
T
235.5
235
–40
–20
0
20
40
60
TEMPERATURE – C
80 85
Figure 6. Power-Down RESET Delay
vs. Temperature ADM8_R
0.999
–40
–20
0
20
40
60
TEMPERATURE – C
80 85
Figure 7. Normalized RESET Voltage
Threshold vs. Temperature
CH1 2.00V CH2
2.00V M 200ms CH1
2.00V
Figure 8. RESET Output Voltage vs.
Supply Voltage
400
350
300
250
200
150
ADM8_L/M
100
ADM8_R/S/T
50
0
1
10
100
1000
RESET COMPARATOR OVERDRIVE, VTH – VCC (mV)
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 VCC. This enables the part to be used in both 3 V
and 5 V or any nominal voltage within the minimum and maximum specifications for VCC. Because of this design approach,
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.
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.
VCC
VCC
ADM809
RESET
PRIORITY ENCODER
74LS147
4 LINE BCD
TO µP
VCC
VCC
GND
ADM809
RESET
OTHER SENSING
DEVICES
Figure 10. Ensuring a Valid RESET Output Down to
VCC = 0 V
GND
Figure 11. Interfacing to µ Ps with Multiple Interrupts
REV. 0
–5–
ADM809/ADM810
OUTLINE DIMENSIONS
Dimensions shown in inches and (mm).
Surface Mount Package
RT-3
0.0550 (1.397)
0.0470 (1.194)
3
1
2
C3047–12–4/97
0.1200 (3.048)
0.1102 (2.799)
0.1040 (2.642)
0.0827 (2.101)
PIN 1
0.0236 (0.599)
0.0177 (0.450)
0.0413 (1.049)
0.0374 (0.950)
0.0807 (2.050)
0.0701 (1.781)
SEATING
PLANE
0.0210 (0.533)
0.0146 (0.371)
0.0059 (0.150)
0.0034 (0.086)
0.0100 (0.254) 0.027 (0.686)
REF
0.0050 (0.127)
PRINTED IN U.S.A.
0.0040 (0.102)
0.0005 (0.013)
0.0440 (1.118)
0.0320 (0.813)
–6–
REV. 0
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