AD ADM8320 Supervisory circuits with watchdog and manual reset in 5-lead sot-23 Datasheet

Supervisory Circuits with Watchdog
and Manual Reset in 5-Lead SOT-23
ADM8316/ADM8318/ADM8319/ADM8320/ADM8321/ADM8322
FEATURES
FUNCTIONAL BLOCK DIAGRAMS
ADM8316
VCC
VCC
RESET
GENERATOR
VREF
MR
RESET
DEBOUNCE
WATCHDOG
DETECTOR
GND
11779-001
26 reset threshold options
2.5 V to 5 V in 100 mV increments
4 reset timeout options
1 ms, 20 ms, 140 ms, and 1120 ms (minimum)
4 watchdog timeout options
6.3 ms, 102 ms, 1.6 sec, and 25.6 sec (typical)
Manual reset input
Multiple reset output options
Low power consumption
Specified over wide temperature range (−40°C to +125°C)
Qualified for automotive applications
5-lead SOT-23 package
WDI
Figure 1. ADM8316
APPLICATIONS
ADM8320
Automotive infotainment
Microprocessor systems
Computers
Controllers
Intelligent instruments
Portable equipment
VCC
RESET
GENERATOR
VREF
MR
RESET
DEBOUNCE
WATCHDOG
DETECTOR
GND
WDI
11779-002
Data Sheet
Figure 2. ADM8320
GENERAL DESCRIPTION
The ADM8316/ADM8318/ADM8319/ADM8320/ADM8321/
ADM8322 are supervisory circuits that monitor power supply
voltage levels and code execution integrity in microprocessorbased systems. As well as providing power-on reset signals, an
on-chip watchdog timer can reset the microprocessor if it fails
to strobe within a preset timeout period. A reset signal can also
be asserted by an external push-button switch through a manual
reset input. The six devices feature different combinations of
watchdog input, manual reset input, and output stage
configuration, as shown in Table 6.
Rev. 0
Each device is available in a choice of 26 reset threshold options
ranging from 2.5 V to 5 V in 100 mV increments. There are also
four reset timeout options of 1 ms, 20 ms, 140 ms, and 1120 ms
(minimum) and four watchdog timeout options of 6.3 ms, 102 ms,
1.6 sec, and 25.6 sec (typical).
The ADM8316/ADM8318/ADM8319/ADM8320/ADM8321/
ADM8322 are available in 5-lead SOT-23 packages and
typically consume only 10 µA, making them suitable for use in
low power, portable applications.
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ADM8316/ADM8318/ADM8319/ADM8320/ADM8321/ADM8322
Data Sheet
TABLE OF CONTENTS
Features .............................................................................................. 1
Open-Drain RESET Output ..................................................... 10
Applications ....................................................................................... 1
Manual Reset Input .................................................................... 10
Functional Block Diagrams ............................................................. 1
Watchdog Input .......................................................................... 10
General Description ......................................................................... 1
Applications Information .............................................................. 11
Revision History ............................................................................... 2
Watchdog Input Current ........................................................... 11
Specifications..................................................................................... 3
Negative Going VCC Transients................................................. 11
Absolute Maximum Ratings............................................................ 5
Ensuring Reset Valid to VCC = 0 V ........................................... 11
ESD Caution .................................................................................. 5
Watchdog Software Considerations ......................................... 11
Pin Configurations and Function Descriptions ........................... 6
Options ............................................................................................ 12
Typical Performance Characteristics ............................................. 7
Outline Dimensions ....................................................................... 14
Theory of Operation ...................................................................... 10
Ordering Guide .......................................................................... 14
Circuit Description..................................................................... 10
Automotive Products ................................................................. 15
Push-Pull Reset Output ............................................................. 10
REVISION HISTORY
10/13—Revision 0: Initial Version
Rev. 0 | Page 2 of 16
Data Sheet
ADM8316/ADM8318/ADM8319/ADM8320/ADM8321/ADM8322
SPECIFICATIONS
VCC = (VTH + 1.5%) to 5.5 V, TA = −40°C to +125°C, unless otherwise noted. Typical values are at TA = 25°C.
Table 1.
Parameter
SUPPLY
VCC Operating Voltage Range 1
VCC that Guarantees Valid Output
Supply Current (WDI Floating)
RESET THRESHOLD VOLTAGE 2
RESET THRESHOLD TEMPERATURE COEFFICIENT
RESET THRESHOLD HYSTERESIS
RESET TIMEOUT PERIOD
Reset Timeout Option A
Reset Timeout Option B
Reset Timeout Option C
Reset Timeout Option D
VCC TO RESET DELAY, tRD
PUSH-PULL OUTPUT (ADM8316, ADM8318, ADM8319,
ADM8321, ADM8322)
RESET Output Voltage
Min
Typ
0.9
0.9
VTH − 1%
VTH − 1.5%
Max
Unit
Test Conditions/Comments
5.5
V
V
µA
µA
V
V
ppm/°C
mV
VCC = 5.5 V
VCC = 3.6 V
TA = 25°C
TA = −40°C to +125°C
10
10
VTH
VTH
20
2.5 × VTH
20
18
VTH + 1%
VTH + 1.5%
1.4
28
200
1600
90
1.8
36
260
2080
See Table 7
1
20
140
1120
0.2
0.2
0.2
0.3
0.9 × VCC
0.9 × VCC
50
RESET Rise Time
RESET Output Voltage
100
V
V
V
V
V
V
ns
0.2
0.3
V
V
V
V
0.2
0.2
0.2
0.3
1
V
V
V
V
µA
6.3
102
1.6
25.6
8.1
132
2.24
33.2
35
0.7 × VCC
100
ms
ms
sec
sec
ns
V
µA
0.9 × VCC
0.9 × VCC
OPEN-DRAIN OUTPUT (ADM8320, ADM8321, ADM8322)
RESET Output Voltage
Open-Drain Reset Output Leakage Current
WATCHDOG INPUT (ADM8316, ADM8318, ADM8320,
ADM8321)
Watchdog Timeout Period, tWD
Watchdog Timeout Option W
Watchdog Timeout Option X
Watchdog Timeout Option Y
Watchdog Timeout Option Z
WDI Pulse Width
WDI Input Threshold
WDI Input Current
ms
ms
ms
ms
µs
VCC falling at 1 mV/µs
VCC ≥ 0.9 V, ISINK = 25 µA
VCC ≥ 1.2 V, ISINK = 100 µA
VCC ≥ 2.7 V, ISINK = 1.2 mA
VCC ≥ 4.5 V, ISINK = 3.2 mA
VCC ≥ 2.7 V, ISOURCE = 500 µA
VCC ≥ 4.5 V, ISOURCE = 800 µA
From 10% to 90% VCC, CL = 5 pF,
VCC = 3.3 V
VCC ≥ 2.7 V, ISINK = 1.2 mA
VCC ≥ 4.5 V, ISINK = 3.2 mA
VCC ≥ 2.7 V, ISOURCE = 500 µA
VCC ≥ 4.5 V, ISOURCE = 800 µA
VCC ≥ 0.9 V, ISINK = 25 µA
VCC ≥ 1.2 V, ISINK = 100 µA
VCC ≥ 2.7 V, ISINK = 1.2 mA
VCC ≥ 4.5 V, ISINK = 3.2 mA
See Table 8
4.5
72
1.12
18.0
50
0.3 × VCC
Rev. 0 | Page 3 of 16
VIL = 0.3 × VCC, VIH = 0.7 × VCC
ADM8316/ADM8318/ADM8319/ADM8320/ADM8321/ADM8322
Parameter
MANUAL RESET INPUT (ADM8316, ADM8319, ADM8320,
ADM8322)
VIL
VIH
MR Input Pulse Width
MR Glitch Rejection
MR Pull-Up Resistance
MR to Reset Delay
1
2
Min
Typ
Max
Unit
Test Conditions/Comments
0.8
V
V
µs
ns
kΩ
ns
VCC = 5 V
2.0
1
35
100
75
350
Data Sheet
125
The device switches from undervoltage reset to normal operation when 1.5 V < VCC < 2.5 V.
The device monitors VCC through an internal factory trimmed voltage divider that programs the nominal reset threshold. Factory-trimmed reset thresholds are
available in approximately 100 mV increments from 2.5 V to 5 V.
Rev. 0 | Page 4 of 16
Data Sheet
ADM8316/ADM8318/ADM8319/ADM8320/ADM8321/ADM8322
ABSOLUTE MAXIMUM RATINGS
TA = 25°C, unless otherwise noted.
Table 2.
Parameter
VCC
All Other Pins
Output Current (RESET, RESET)
Operating Temperature Range
Storage Temperature Range
θJA Thermal Impedance, SOT-23
Lead Temperature
Soldering (10 sec)
Vapor Phase (60 sec)
Infrared (15 sec)
Rating
−0.3 V to +6 V
−0.3 V to (VCC + 0.3 V)
20 mA
−40°C to +125°C
−65°C to +150°C
270°C/W
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 indicated in the operational
section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.
ESD CAUTION
300°C
215°C
220°C
Rev. 0 | Page 5 of 16
ADM8316/ADM8318/ADM8319/ADM8320/ADM8321/ADM8322
Data Sheet
RESET 1
GND 2
MR 3
ADM8316/
ADM8320
TOP VIEW
(Not to Scale)
5
VCC
4
WDI
11779-003
PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS
Figure 3. ADM8316/ADM8320 Pin Configuration
Table 3. ADM8316/ADM8320 Pin Function Descriptions
Mnemonic
RESET
2
3
GND
MR
4
WDI
5
VCC
Description
Active Low Reset Output. Asserted whenever VCC is below the reset threshold, VTH. This pin is a push-pull
output stage for the ADM8316 and an open-drain output stage for the ADM8320.
Ground.
Manual Reset Input. This is an active low input that, when forced low for greater than the glitch filter time,
generates a reset. It features a 75 kΩ internal pull-up resistor.
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
this pin floating to disable the watchdog timer.
Power Supply Voltage Being Monitored.
RESET 1
GND 2
RESET 3
ADM8318/
ADM8321
TOP VIEW
(Not to Scale)
5
VCC
4
WDI
11779-004
Pin No.
1
Figure 4. ADM8318/ADM8321 Pin Configuration
Table 4. ADM8318/ADM8321 Pin Function Descriptions
Mnemonic
RESET
2
3
4
GND
RESET
WDI
5
VCC
Description
Active Low Reset Output. Asserted whenever VCC is below the reset threshold, VTH. This pin is a push-pull
output stage for the ADM8318 and an open-drain output stage for the ADM8321.
Ground.
Active High Push-Pull Reset Output.
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
this pin floating to disable the watchdog timer.
Power Supply Voltage Being Monitored.
RESET 1
GND 2
RESET 3
ADM8319/
ADM8322
TOP VIEW
(Not to Scale)
5
VCC
4
MR
11779-005
Pin No.
1
Figure 5. ADM8319/ADM8322 Pin Configuration
Table 5. ADM8319/ADM8322 Pin Function Descriptions
Pin No.
1
Mnemonic
RESET
2
3
4
GND
RESET
MR
5
VCC
Description
Active low Reset Output. Asserted whenever VCC is below the reset threshold, VTH. This pin is a push-pull
output stage for the ADM8319 and an open-drain output stage for the ADM8322.
Ground.
Active High Push-Pull Reset Output.
Manual Reset Input. This is an active low input that, when forced low for greater than the glitch filter time,
generates a reset. It features a 75 kΩ internal pull-up resistor.
Power Supply Voltage Being Monitored.
Rev. 0 | Page 6 of 16
Data Sheet
ADM8316/ADM8318/ADM8319/ADM8320/ADM8321/ADM8322
TYPICAL PERFORMANCE CHARACTERISTICS
14
100
13
90
12
VCC TO RESET DELAY (µs)
10
VCC = 3.0V
9
ICC (µA)
80
VCC = 5.0V
11
8
VCC = 1.5V
7
6
5
4
3
70
VTH = 5V
60
VTH = 2.93V
50
VTH = 2.5V
40
30
20
2
–20
0
20
40
60
80
100
120
TEMPERATURE (°C)
0
–40
11779-006
0
–40
–20
0
20
40
60
80
100
120
TEMPERATURE (°C)
Figure 6. Supply Current (ICC) vs. Temperature
11779-009
10
1
Figure 9. VCC to Reset Delay vs. Temperature
12
500
450
10
PROPAGATION DELAY (ns)
400
ICC (µA)
8
6
4
VTH = 2.5V
350
VTH = 2.93V
300
250
VTH = 5V
200
150
100
2
0.4 0.8 1.2 1.6 2.0 2.4 2.8 3.2 3.6 4.0 4.4 4.8 5.2 5.6
VCC (V)
0
–40
0
20
40
60
80
100
120
TEMPERATURE (°C)
Figure 10. Manual Reset to Reset Propagation Delay vs. Temperature
Figure 7. Supply Current (ICC) vs. Supply Voltage (VCC)
1.05
1.20
1.04
NORMALIZED RESET TIMEOUT
1.15
1.03
1.02
1.01
1.00
0.99
0.98
0.97
1.10
1.05
1.00
0.95
0.90
0.85
0.96
0.95
–40
–20
0
20
40
60
80
100
TEMPERATURE (°C)
120
0.80
–40
11779-008
NORMALIZED RESET THRESHOLD
–20
–20
0
20
40
60
80
100
120
TEMPERATURE (°C)
Figure 11. Normalized Reset Timeout vs. Temperature
Figure 8. Normalized Reset Threshold vs. Temperature
Rev. 0 | Page 7 of 16
11779-011
0
11779-007
0
11779-010
50
ADM8316/ADM8318/ADM8319/ADM8320/ADM8321/ADM8322
9
1.20
8
NEGATIVE PULSE
1.15
MINIMUM PULSE WIDTH (ns)
NORMALIZED WATCHDOG TIMEOUT
Data Sheet
1.10
1.05
1.00
7
6
POSITIVE PULSE
5
4
3
2
0.95
–20
0
20
40
60
80
100
120
TEMPERATURE (°C)
0
–40
11779-012
0.90
–40
40
60
80
0.308
100
120
ISINK = 3.2mA
ISINK = 800µA
140
0.258
VTH = 2.93V
120
RESET VOLTAGE (V)
VTH = 5V
100
80
VTH = 4.63V
60
0.208
0.158
0.108
40
100
1000
OVERDRIVE VOLTAGE (mV)
Figure 13. Maximum VCC Transient Duration vs. RESET Threshold Overdrive
1.3
1.5
1.7
1.9
2.1
2.3
2.5
2.7
2.9
VCC VOLTAGE (V)
Figure 16. RESET Open-Drain VOL Voltage vs. VCC Voltage (VTH = 3 V)
0.30
ISINK = 3.2mA
ISINK = 800µA
0.25
RESET VOLTAGE (V)
VTH = 2.93V
VTH = 2.5V
0.20
0.15
0.10
VTH = 5V
–20
0
20
40
60
TEMPERATURE (°C)
80
100
120
0
1.1 1.3 1.5 1.7 1.9 2.1 2.3 2.5 2.7 2.9 3.1 3.3 3.5 3.7 3.9
VCC VOLTAGE (V)
Figure 17. RESET Push-Pull VOL Voltage vs. VCC Voltage (VTH = 4 V)
Figure 14. Manual Reset (MR) Minimum Pulse Width vs. Temperature
Rev. 0 | Page 8 of 16
11779-017
0.05
11779-014
850
840
830
820
810
800
790
780
770
760
750
740
730
720
710
700
690
680
670
660
650
–40
0.008
1.1
11779-016
0.058
20
11779-013
MAXIMUM TRANSIENT DURATION (µs)
20
Figure 15. Watchdog Input Minimum Pulse Width vs. Temperature
RESET ASSERTED ABOVE CURVE
0
10
MR MINIMUM PULSE WIDTH (ns)
0
TEMPERATURE (°C)
Figure 12. Normalized Watchdog Timeout vs. Temperature
160
–20
11779-015
1
Data Sheet
3.5
ADM8316/ADM8318/ADM8319/ADM8320/ADM8321/ADM8322
25
ISOURCE = 3.2mA
ISOURCE = 800µA
24
3.0
RISE TIME (ns)
2.0
1.5
22
21
20
19
1.0
18
0.5
1.3
1.5
1.7
1.9
2.1
2.3
2.5
2.7
2.9
VCC VOLTAGE (V)
16
2.6 2.8 3.0 3.2 3.4 3.6 3.8 4.0 4.2 4.4 4.6 4.8 5.0 5.2 5.4
VCC VOLTAGE (V)
Figure 19. RESET Push-Pull Rise Time vs. VCC Voltage
Figure 18. RESET Push-Pull VOH Voltage vs. VCC Voltage (VTH = 3 V)
Rev. 0 | Page 9 of 16
11779-019
0
1.1
17
11779-018
RESET VOLTAGE (V)
23
2.5
ADM8316/ADM8318/ADM8319/ADM8320/ADM8321/ADM8322
Data Sheet
THEORY OF OPERATION
CIRCUIT DESCRIPTION
MANUAL RESET INPUT
The ADM8316/ADM8318/ADM8319/ADM8320/ADM8321/
ADM8322 provide microprocessor supply voltage supervision
by controlling the microprocessor reset input. Code execution
errors are avoided during power-up, power-down, and
brownout conditions by asserting a reset signal when the supply
voltage is below a preset threshold and by allowing supply
voltage stabilization with a fixed timeout reset delay after the
supply voltage rises above the threshold. In addition, problems
with microprocessor code execution can be monitored and
corrected with a watchdog timer (ADM8316/ADM8318/
ADM8320/ADM8321). If the user detects a problem with
system operation, a manual reset input is available (ADM8316/
ADM8319/ADM8320/ADM8322) to reset the microprocessor,
for example, by means of an external push-button switch.
The ADM8316/ADM8319/ADM8320/ADM8322 feature a
manual reset input (MR), which when driven low, asserts the reset
output. When MR transitions from low to high, the reset
remains asserted for the duration of the reset active timeout
period before deasserting. The MR input has a 75 kΩ, internal
pull-up resistor so that the input is always high when
unconnected. An external push-button switch can be connected
between MR and ground so that the user can generate a reset.
Debounce circuitry for this purpose is integrated on chip. Noise
immunity is provided on the MR input, and fast, negative going
transients of up to 100 ns (typical) are ignored. A 0.1 μF capacitor
between MR and ground provides additional noise immunity.
PUSH-PULL RESET OUTPUT
The ADM8316/ADM8318/ADM8320/ADM8321 feature a
watchdog timer that monitors microprocessor activity. A timer
circuit is cleared with every low-to-high or high-to-low logic
transition on the watchdog input pin (WDI), which detects pulses
as short as 50 ns. If the timer counts through the preset
watchdog timeout period (tWD), a reset is asserted. The microprocessor is required to toggle the WDI pin to avoid asserting
the reset pin. Failure of the microprocessor to toggle WDI
within the timeout period, therefore, indicates a code execution
error, and the reset pulse generated restarts the microprocessor
in a known state.
The reset output is asserted when VCC is below the reset threshold (VTH), when MR is driven low, or when WDI is not serviced
within the watchdog timeout period (tWD). The reset output
remains asserted for the duration of the reset active timeout
period (tRP) after VCC rises above the reset threshold, after MR
transitions from low to high, or after the watchdog timer times
out. Figure 20 illustrates the behavior of the reset outputs.
VCC
VCC
VTH
VTH
1V
0V
As well as logic transitions on WDI, the watchdog timer is also
cleared by a reset assertion due to an undervoltage condition on
VCC or due to MR being pulled low. When a reset asserts, the
watchdog timer clears and does not begin counting again until
the reset deassserts. The watchdog timer can be disabled by
leaving WDI floating or by tristating the WDI driver.
VCC
tRP
0V
RESET
VCC
1V
0V
VCC
tRD
RESET
tRP
tRD
11779-020
RESET
Figure 20. Reset Timing Diagram
VCC
1V
0V
VCC
0V
WDI
VTH
tRP
tWD
VCC
0V
Figure 21. Watchdog Timing Diagram
OPEN-DRAIN RESET OUTPUT
The ADM8320/ADM8321/ADM8322 have an active low, opendrain reset output. This output structure requires an external
pull-up resistor to connect the reset output to a voltage rail no
higher than VCC. A resistor that complies with the logic low and
logic high voltage level requirements of the microprocessor
while supplying input current and leakage paths on the RESET
line is recommended. A 10 kΩ resistor is adequate in most
situations.
Rev. 0 | Page 10 of 16
tRP
11779-021
The ADM8316 features an active low push-pull reset output,
whereas the ADM8321/ADM8322 have active high push-pull
reset outputs. The ADM8318/ADM8319 feature dual active low
and active high push-pull reset outputs. For active low and
active high outputs, the reset signal is guaranteed to be valid for
VCC down to 0.9 V.
WATCHDOG INPUT
Data Sheet
ADM8316/ADM8318/ADM8319/ADM8320/ADM8321/ADM8322
APPLICATIONS INFORMATION
WATCHDOG INPUT CURRENT
WATCHDOG SOFTWARE CONSIDERATIONS
To minimize the watchdog input current, leave WDI low for the
majority of the watchdog timeout period. When driven high,
WDI can draw as much as 100 µA. Pulsing WDI low to high to
low at a low duty cycle reduces the effect of the large input
current. When WDI is unconnected, a window comparator
disconnects the watchdog timer from the reset output circuitry
so that a reset is not asserted when the watchdog timer times out.
In implementing the microprocessor watchdog strobe code,
quickly switching WDI low to high and then high to low (minimizing WDI high time) is desirable for current consumption
reasons. However, a more effective way of using the watchdog
function can be considered.
NEGATIVE GOING VCC TRANSIENTS
To avoid unnecessary resets caused by fast power supply transients,
the ADM8316/ADM8318/ADM8319/ADM8320/ADM8321/
ADM8322 are equipped with glitch rejection circuitry. The typical
performance characteristic in Figure 13 plots VCC transient
duration vs. reset threshold overdrive. The curves show
combinations of reset threshold overdrive and duration for
which a reset is not generated for 5 V, 4.63 V, and 2.93 V reset
threshold devices. For example, with the 2.93 V threshold, a
transient that goes 100 mV below the threshold and lasts 80 µs
typically does not cause a reset, but if the transient is any larger
in reset threshold overdrive or duration, a reset generates. An
optional 0.1 µF bypass capacitor mounted near VCC provides
additional glitch rejection.
A low to high to low WDI pulse within a given subroutine
prevents the watchdog from timing out. However, if the subroutine becomes stuck in an infinite loop, the watchdog cannot
detect this because the subroutine continues to toggle WDI. A
more effective coding scheme for detecting this error involves
using a slightly longer watchdog timeout. In the program that
calls the subroutine, WDI is set high. The subroutine sets WDI
low when it is called. If the program executes without error, WDI
is toggled high and low with every loop of the program. If the
subroutine enters an infinite loop, WDI is kept low, the watchdog
times out, and the microprocessor is reset (see Figure 23).
ENSURING RESET VALID TO VCC = 0 V
START
SET WDI
HIGH
RESET
PROGRAM
CODE
SUBROUTINE
SET WDI
LOW
RETURN
Figure 23. Watchdog Flow Diagram
VCC
VCC
VCC
RESET
100kΩ
100kΩ
ADM8318/
ADM8319/
ADM8321/
ADM8322
MR
WDI
RESET
MICROPROCESSOR
I/O
11779-024
RESET
ADM8316
RESET
11779-022
ADM8316/
ADM8318/
ADM8319
INFINITE LOOP:
WATCHDOG
TIMES OUT
11779-023
Both active low and active high reset outputs are guaranteed
to be valid for VCC as low as 0.9 V. However, by using an
external resistor with push-pull configured reset outputs, valid
outputs for VCC as low as 0 V are possible. For an active low reset
output, a resistor connected between RESET and ground pulls
the output low when it is unable to sink current. For an active
high reset output, a resistor connected between RESET and VCC
pulls the output high when it is unable to source current. Use a
large resistance, such as 100 kΩ, so that it does not overload the
reset output when VCC is greater than 0.9 V.
Figure 22. Ensuring Reset Valid to VCC = 0 V
Rev. 0 | Page 11 of 16
Figure 24. Typical Application Circuit
ADM8316/ADM8318/ADM8319/ADM8320/ADM8321/ADM8322
Data Sheet
OPTIONS
Table 6. Selection Table
Output Stage
Device No.
ADM8316
ADM8318
ADM8319
ADM8320
ADM8321
ADM8322
Watchdog
Yes
Yes
No
Yes
Yes
No
Manual Reset
Yes
No
Yes
Yes
No
Yes
RESET
Typical
1.4
28
200
1600
Maximum
1.8
36
260
2080
Unit
ms
ms
ms
ms
Typical
6.3
102
1.6
25.6
Maximum
8.1
132
2.24
33.2
Unit
ms
ms
sec
sec
RESET
No
Push-pull
Push-pull
No
Push-pull
Push-pull
Push-pull
Push-pull
Push-pull
Open-drain
Open-drain
Open-drain
Table 7. Reset Timeout Options
Suffix
A
B
C
D
Minimum
1
20
140
1120
Table 8. Watchdog Timeout Options
Suffix
W
X
Y
Z
Minimum
4.5
72
1.12
18.0
Table 9. Reset Voltage Threshold Options
Reset Threshold Number
50
49
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
Minimum
4.950
4.851
4.752
4.653
4.584
4.455
4.346
4.257
4.158
4.059
3.960
3.861
3.762
3.663
3.564
3.465
3.366
3.267
3.168
3.049
2.970
2.901
2.772
2.673
2.604
2.475
TA = 25°C
Typical
5.000
4.900
4.800
4.700
4.630
4.500
4.390
4.300
4.200
4.100
4.00
3.900
3.800
3.700
3.600
3.500
3.400
3.300
3.200
3.080
3.000
2.930
2.800
2.700
2.630
2.500
Maximum
5.050
4.949
4.848
4.747
4.676
4.545
4.434
4.343
4.242
4.141
4.040
3.939
3.838
3.737
3.636
3.535
3.434
3.333
3.232
3.111
3.030
2.959
2.828
2.727
2.656
2.525
Rev. 0 | Page 12 of 16
Minimum
4.925
4.826
4.728
4.629
4.560
4.432
4.324
4.235
4.137
4.038
3.940
3.841
3.743
3.644
3.546
3.447
3.349
3.250
3.152
3.033
2.955
2.886
2.758
2.659
2.590
2.462
TA = −40°C to +125°C
Maximum
5.075
4.974
4.872
4.771
4.700
4.568
4.456
4.365
4.263
4.162
4.060
3.959
3.857
3.756
3.654
3.553
3.451
3.350
3.248
3.127
3.045
2.974
2.842
2.741
2.670
2.538
Unit
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
Data Sheet
ADM8316/ADM8318/ADM8319/ADM8320/ADM8321/ADM8322
Table 10. Standard Models
Model
ADM8316WBX30ARJZR7
ADM8316WBX46ARJZR7
ADM8318WCY46ARJZR7
ADM8319WB31ARJZR7
ADM8320WCY29ARJZR7
ADM8321WAY30ARJZR7
ADM8321WCY46ARJZR7
ADM8322WC46ARJZR7
Reset Threshold (V)
3
4.63
4.63
3.08
2.93
3
4.63
4.63
Minimum Reset Timeout (ms)
20
20
140
20
140
1
140
140
Rev. 0 | Page 13 of 16
Typical Watchdog Timeout (sec)
0.102
0.102
1.6
Not applicable
1.6
1.6
1.6
Not applicable
ADM8316/ADM8318/ADM8319/ADM8320/ADM8321/ADM8322
Data Sheet
OUTLINE DIMENSIONS
3.00
2.90
2.80
5
1.70
1.60
1.50
4
1
2
3.00
2.80
2.60
3
0.95 BSC
1.90
BSC
1.45 MAX
0.95 MIN
0.15 MAX
0.05 MIN
0.50 MAX
0.35 MIN
0.20 MAX
0.08 MIN
SEATING
PLANE
10°
5°
0°
0.60
BSC
0.55
0.45
0.35
COMPLIANT TO JEDEC STANDARDS MO-178-AA
11-01-2010-A
1.30
1.15
0.90
Figure 25. 5-Lead Small Outline Transistor Package [SOT-23]
(RJ-5)
Dimensions shown in millimeters
ADM83 _ _ W_ _ _ _ ARJZR7
ORDERING QUANTITY
R7: 3000-PIECE REEL, RoHS COMPLIANT
GENERIC NUMBER
(16 TO 22)
Z: RoHS COMPLIANT
W: AUTOMOTIVE QUAL
PACKAGE CODE
RJ: 5-LEAD SOT-23
RESET TIMEOUT PERIOD
A: 1ms (MIN)
B: 20ms (MIN)
C: 140ms (MIN)
D: 1120ms (MIN)
TEMPERATURE RANGE
A: –40°C TO +125°C
RESET THRESHOLD NUMBER
(25 TO 50)
11779-025
WATCHDOG TIMEOUT PERIOD
W: 6.3ms (TYP)
X: 102ms (TYP)
Y: 1.6sec (TYP)
Z: 25.6sec (TYP)
Figure 26. Ordering Code Structure
ORDERING GUIDE
Model 1, 2, 3, 4
ADM8316WxxxxARJZR7
ADM8318WxxxxARJZR7
ADM8319WxxxARJZR7
ADM8320WxxxxARJZR7
ADM8321WxxxxARJZR7
ADM8322WxxxARJZR7
Temperature Range
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
Ordering Quantity 5
3,000
3,000
3,000
3,000
3,000
3,000
Package Description
5-Lead SOT-23
5-Lead SOT-23
5-Lead SOT-23
5-Lead SOT-23
5-Lead SOT-23
5-Lead SOT-23
Package Option
RJ-5
RJ-5
RJ-5
RJ-5
RJ-5
RJ-5
Branding
LMT
LMW
LMV
LMX
LMY
LMZ
Complete the ordering code by inserting the reset timeout, watchdog timeout, and reset threshold (ADM8316/ADM8318/ADM8320/ADM8321) suffixes from Table 7
to Table 9. No watchdog timeout is available for ADM8319/ADM8322.
Contact sales for the availability of nonstandard models. See Table 10 for a list of standard models.
3
Z = RoHS Compliant Part.
4
W = Qualified for Automotive Applications.
5
A minimum of 12,000 (four reels) must be ordered for nonstandard models.
1
2
Rev. 0 | Page 14 of 16
Data Sheet
ADM8316/ADM8318/ADM8319/ADM8320/ADM8321/ADM8322
AUTOMOTIVE PRODUCTS
The ADM8316W/ADM8318W/ADM8319W/ADM8320W/ADM8321W/ADM8322W models are available with controlled
manufacturing to support the quality and reliability requirements of automotive applications. Note that these automotive models may
have specifications that differ from the commercial models; therefore, designers should review the Specifications section of this data sheet
carefully. Only the automotive grade products shown are available for use in automotive applications. Contact your local Analog Devices
account representative for specific product ordering information and to obtain the specific Automotive Reliability reports for these
models.
Rev. 0 | Page 15 of 16
ADM8316/ADM8318/ADM8319/ADM8320/ADM8321/ADM8322
NOTES
©2013 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D11779-0-10/13(0)
Rev. 0 | Page 16 of 16
Data Sheet