General Description
The MAX6715MAX6729 are ultra-low-voltage microproces-
sor (P) supervisory circuits designed to monitor two or three
system power-supply voltages. These devices assert a sys-
tem reset if any monitored supply falls below its factory-
trimmed or adjustable threshold and maintain reset for a
minimum timeout period after all supplies rise above their
thresholds. The integrated dual/triple supervisory circuits sig-
nificantly improve system reliability and reduce size com-
pared to separate ICs or discrete components.
These devices monitor primary supply voltages (V
CC
1) from
1.8V to 5.0V and secondary supply voltages (V
CC
2) from
0.9V to 3.3V with factory-trimmed reset threshold voltage
options (see Reset Voltage Threshold Suffix Guide). An
externally adjustable RSTIN input option allows customers to
monitor a third supply voltage down to 0.62V. These devices
are guaranteed to be in the correct reset output logic state
when either V
CC
1 or V
CC
2 remains greater than 0.8V.
A variety of push-pull or open-drain reset outputs along with
watchdog input, manual reset input, and power-fail input/out-
put features are available (see Selector Guide). Select reset
timeout periods from 1.1ms to 1120ms (min) (see Reset
Timeout Period Suffix Guide). The MAX6715MAX6729 are
available in small 5, 6, and 8-pin SOT23 packages and oper-
ate over the -40C to +85C temperature range.
Applications
Multivoltage Systems
Telecom/Networking Equipment
Computers/Servers
Portable/Battery-Operated Equipment
Industrial Equipment
Printer/Fax
Set-Top Boxes
Features
o V
CC
1 (primary supply) Reset Threshold Voltages
from 1.58V to 4.63V
o V
CC
2 (secondary supply) Reset Threshold
Voltages from 0.79V to 3.08V
o Externally Adjustable RSTIN Threshold for
Auxiliary/Triple-Voltage Monitoring
(0.62V internal reference)
o Watchdog Timer Option
35s (min) Long Startup Period
1.12s (min) Normal Timeout Period
o Manual Reset Input Option
o Power-Fail Input/Power-Fail Output Option
(Push-Pull and Open-Drain Active-Low)
o Guaranteed Reset Valid Down to V
CC
1 or
V
CC
2 = 0.8V
o Reset Output Logic Options
o Immune to Short V
CC
Transients
o Low Supply Current 14A (typ) at 3.6V
o Small 5, 6, and 8-Pin SOT23 Packages
MAX6715MAX6729
Dual/Triple Ultra-Low-Voltage SOT23 P
Supervisory Circuits
________________________________________________________________ Maxim Integrated Products
1
Ordering Information
IN
OUT2
OUT1
DC/DC
CONVERTER
UNREGULATED
DC
R1
R2
V
CC
1
V
CC
2
RSTIN/PFI
MR
RST
WDI
PFO
MAX67_ _
PUSHBUTTON
SWITCH
I/O
SUPPLY
CORE
SUPPLY
RESET
I/O
NMI
P
1.8V
0.9V
Typical Operating Circuit
19-2325; Rev 3; 6/03
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim's website at www.maxim-ic.com.
Pin Configurations appear at end of data sheet.
Selector Guide appears at end of data sheet.
PART
TEMP RANGE
PIN-PACKAGE
MAX6715UT_ _D_ -T
-40C to +85C
6 SOT23-6
MAX6716UT_ _D_ -T
-40C to +85C
6 SOT23-6
MAX6717UK_ _D_ -T
-40C to +85C
5 SOT23-5
MAX6718UK_ _D_ -T
-40C to +85C
5 SOT23-5
MAX6719UT_ _D_ -T
-40C to +85C
6 SOT23-6
MAX6720UT_ _D_ -T
-40C to +85C
6 SOT23-6
Note: The first "_ _" are placeholders for the threshold voltage
levels of the devices. Desired threshold levels are set by the part
number suffix found in the Reset Voltage Threshold Suffix Guide.
The "_" after the D is a placeholder for the reset timeout delay
time. Desired delay time is set using the timeout period suffix
found in the Reset Timeout Period Suffix Guide. For example the
MAX6716UTLTD3-T is a dual-voltage supervisor V
TH
1 = 4.625V,
V
TH
2 = 3.075V, and 210ms (typ) timeout period.
Ordering Information continued at end of data sheet.
MAX6715MAX6729
Dual/Triple Ultra-Low-Voltage SOT23 P
Supervisory Circuits
2
_______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(V
CC
1 = V
CC
2 = 0.8V to 5.5V, GND = 0, T
A
= -40C to +85C, unless otherwise noted. Typical values are at T
A
= +25C.) (Note 1)
Stresses beyond those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
Terminal Voltage (with respect to GND)
V
CC
1, V
CC
2 ..........................................................-0.3V to +6V
Open-Drain RST, RST1, RST2, PFO, RST ................-0.3V to +6V
Push-Pull RST, RST1, PFO, RST...............-0.3V to (V
CC
1 + 0.3V)
Push-Pull RST2 .........................................-0.3V to (V
CC
2 + 0.3V)
RSTIN, PFI, MR, WDI ................................................-0.3V to +6V
Input Current/Output Current (all pins) ...............................20mA
Continuous Power Dissipation (T
A
= +70C)
5-Pin SOT23-5 (derate 7.1mW/C above +70C) ........571mW
6-Pin SOT23-6 (derate 8.7mW/C above +70C) ........696mW
8-Pin SOT23-8 (derate 8.9mW/C above +70C) ........714mW
Operating Temperature Range ...........................-40C to +85C
Storage Temperature Range .............................-65C to +150C
Junction Temperature ......................................................+150C
Lead Temperature (soldering, 10s) .................................+300C
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Supply Voltage
V
CC
0.8
5.5
V
V
CC
1 < 5.5V, all I/O pins open
15
39
I
CC1
V
CC
1 < 3.6V, all I/O pins open
10
28
V
CC
2 < 3.6V, all I/O pins open
4
11
Supply Current
I
CC2
V
CC
2 < 2.75V, all I/O pins open
3
9
A
L (falling)
4.500
4.625
4.750
M (falling)
4.250
4.375
4.500
T (falling)
3.000
3.075
3.150
S (falling)
2.850
2.925
3.000
R (falling)
2.550
2.625
2.700
Z (falling)
2.250
2.313
2.375
Y (falling)
2.125
2.188
2.250
W (falling)
1.620
1.665
1.710
V
CC
1 Reset Threshold
V
TH1
V (falling)
1.530
1.575
1.620
V
T (falling)
3.000
3.075
3.150
S (falling)
2.850
2.925
3.000
R (falling)
2.550
2.625
2.700
Z (falling)
2.250
2.313
2.375
Y (falling)
2.125
2.188
2.250
W (falling)
1.620
1.665
1.710
V (falling)
1.530
1.575
1.620
I (falling)
1.350
1.388
1.425
H (falling)
1.275
1.313
1.350
G (falling)
1.080
1.110
1.140
F (falling)
1.020
1.050
1.080
E (falling)
0.810
0.833
0.855
V
CC
2 Reset Threshold
V
TH2
D (falling)
0.765
0.788
0.810
V
Reset Threshold Tempco
20
ppm/C
Reset Threshold Hysteresis
V
HYST
Referenced to V
TH
typical
0.5
%
MAX6715MAX6729
Dual/Triple Ultra-Low-Voltage SOT23 P
Supervisory Circuits
_______________________________________________________________________________________
3
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
1 = V
CC
2 = 0.8V to 5.5V, GND = 0, T
A
= -40C to +85C, unless otherwise noted. Typical values are at T
A
= +25C.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
V
CC
to Reset Output Delay
t
RD
V
C C
1 = ( V
TH
1
+ 100m V ) to ( V
TH
1 - 100m V ) or
V
C C
2 = ( V
TH
2 + 75m V ) to ( V
TH
2 - 75m V )
20
s
D1
1.1
1.65
2.2
D2
8.8
13.2
17.6
D3
140
210
280
D5
280
420
560
D6
560
840
1120
Reset Timeout Period
t
RP
D4
1120
1680
2240
ms
ADJUSTABLE RESET COMPARATOR INPUT (MAX6719/MAX6720/MAX6723MAX6727)
RSTIN Input Threshold
V
RSTIN
611
626.5
642
mV
RSTIN Input Current
I
RSTIN
-25
+25
nA
RSTIN Hysteresis
3
mV
RSTIN to Reset Output Delay
t
RSTIND
V
RSTIN
to (V
RSTIN
- 30mV)
22
s
POWER-FAIL INPUT (MAX6728/MAX6729)
PFI Input Threshold
V
PFI
611
626.5
642
mV
PFI Input Current
I
PFI
-25
+25
nA
PFI Hysteresis
V
PFH
3
mV
PFI to
PFO Delay
t
DPF
(V
PFI
+ 30mV) to (V
PFI
- 30mV)
2
s
MANUAL RESET INPUT (MAX6715MAX6722/MAX6725MAX6729)
V
IL
0.3
V
CC
1
MR Input Voltage
V
IH
0.7
V
CC
1
V
MR Minimum Pulse Width
1
s
MR Glitch Rejection
100
ns
MR to Reset Delay
t
MR
200
ns
MR Pullup Resistance
25
50
80
k
WATCHDOG INPUT (MAX6721MAX6729)
First watchdog period after reset timeout
period
35
54
72
Watchdog Timeout Period
t
WD
Normal mode
1.12
1.68
2.24
s
WDI Pulse Width
t
WDI
(Note 2)
50
ns
V
IL
0.3
V
CC
1
WDI Input Voltage
V
IH
0.7
V
CC
1
V
WDI Input Current
I
WDI
WDI = 0 or V
CC
1
-1
+1
A
MAX6715MAX6729
Dual/Triple Ultra-Low-Voltage SOT23 P
Supervisory Circuits
4
_______________________________________________________________________________________
Note 1: Devices tested at +25C. Overtemperature limits are guaranteed by design and not production tested.
Note 2: Parameter guaranteed by design.
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
1 = V
CC
2 = 0.8V to 5.5V, GND = 0, T
A
= -40C to +85C, unless otherwise noted. Typical values are at T
A
= +25C.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
RESET/POWER-FAIL OUTPUTS
V
CC
1 or V
CC
2
0.8V, I
SINK
= 1A,
output asserted
0.3
V
CC
1 or V
CC
2
1.0V, I
SINK
= 50A,
output asserted
0.3
V
CC
1 or V
CC
2
1.2V, I
SINK
= 100A,
output asserted
0.3
V
CC
1 or V
CC
2
2.7V, I
SINK
= 1.2mA,
output asserted
0.3
RST/RST1/RST2/PFO
Output LOW
(Push-Pull or Open-Drain)
V
OL
V
CC
1 or V
CC
2
4.5V, I
SINK
= 3.2mA,
output asserted
0.4
V
V
CC
1
1.8V, I
SOURCE
= 200A, output not
asserted
0.8
V
CC
1
V
CC
1
2.7V, I
SOURCE
= 500A, output not
asserted
0.8
V
CC
1
RST/RST1/PFO
Output HIGH
(Push-Pull Only)
V
OH
V
CC
1
4.5V, I
SOURCE
= 800A, output not
asserted
0.8
V
CC
1
V
V
CC
2
1.8V, I
SOURCE
= 200A, output not
asserted
0.8
V
CC
2
V
CC
2
2.7V, I
SOURCE
= 500A, output not
asserted
0.8
V
CC
2
RST2
Output HIGH
(Push-Pull Only)
V
OH
V
CC
2
4.5V, I
SOURCE
= 800A, output not
asserted
0.8
V
CC
2
V
V
CC
1
1.0V, I
SOURCE
= 1A, reset asserted
0.8
V
CC
1
V
CC
1
1.8V, I
SOURCE
= 150A,
reset asserted
0.8
V
CC
1
V
CC
1
2.7V, I
SOURCE
= 500A,
reset asserted
0.8
V
CC
1
RST
Output HIGH
(Push-Pull Only)
V
OH
V
CC
1
4.5V, I
SOURCE
= 800A,
reset asserted
0.8
V
CC
1
V
V
CC
1 or V
CC
2
1.8V, I
SINK
= 500A,
reset not asserted
0.3
V
CC
1 or V
CC
2
2.7V, I
SINK
= 1.2mA,
reset not asserted
0.3
RST
Output LOW
(Push-Pull or Open Drain)
V
OL
V
CC
1 or V
CC
2
4.5V, I
SINK
= 3.2mA,
reset not asserted
0.4
V
RST/RST1/RST2/PFO Output
Open-Drain Leakage Current
Output not asserted
0.5
A
RST Output Open-Drain
Leakage Current
Output asserted
0.5
A
MAX6715MAX6729
Dual/Triple Ultra-Low-Voltage SOT23 P
Supervisory Circuits
_______________________________________________________________________________________
5
0
4
2
10
8
6
16
14
12
18
-40
10
-15
35
60
85
SUPPLY CURRENT vs. TEMPERATURE
V
CC
1 = 5V, V
CC
2 = 3.3V
MAX6715-29 toc01
TEMPERATURE (
C)
SUPPLY CURRENT (
A)
TOTAL
I
CC
1
I
CC
2
0
4
2
10
8
6
16
14
12
18
-40
10
-15
35
60
85
SUPPLY CURRENT vs. TEMPERATURE
V
CC
1 = 3.3V, V
CC
2 = 2.5V
MAX6715-29 toc02
TEMPERATURE (
C)
SUPPLY CURRENT (
A)
TOTAL
I
CC
1
I
CC
2
0
4
2
10
8
6
16
14
12
18
-40
10
-15
35
60
85
SUPPLY CURRENT vs. TEMPERATURE
V
CC
1 = 2.5V, V
CC
2 = 1.8V
MAX6715-29 toc03
TEMPERATURE (
C)
SUPPLY CURRENT (
A)
TOTAL
I
CC
1
I
CC
2
0
4
2
10
8
6
16
14
12
18
-40
10
-15
35
60
85
SUPPLY CURRENT vs. TEMPERATURE
V
CC
1 = 1.8V, V
CC
2 = 1.2V
MAX6715-29 toc04
TEMPERATURE (
C)
SUPPLY CURRENT (
A)
TOTAL
I
CC
1
I
CC
2
0.998
1.000
0.999
1.003
1.002
1.001
1.006
1.005
1.004
1.007
-40
10
-15
35
60
85
NORMALIZED RESET/WATCHDOG
TIMEOUT PERIOD vs. TEMPERATURE
MAX6715-29 toc05
TEMPERATURE (
C)
RESET/WATCHDOG PERIOD
10,000
1000
100
10
1
100
10
1000
MAXIMUM V
CC
TRANSIENT DURATION
vs. RESET THRESHOLD OVERDRIVE
MAX6715-29 toc06
RESET THRESHOLD OVERDRIVE (mV)
MAXIMUM V
CC
TRANSIENT DURATION (
s)
RESET OCCURS ABOVE
THIS LINE
0.996
0.997
0.998
0.999
1.000
1.001
1.002
1.003
1.004
-40
-15
10
35
60
85
NORMALIZED V
CC
RESET THRESHOLD
vs. TEMPERATURE
MAX6715-29 toc07
TEMPERATURE (
C)
RESET THRESHOLD
625
627
626
629
628
630
631
-40
85
RESET INPUT AND POWER-FAIL INPUT
THRESHOLD vs. TEMPERATURE
MAX6715-29 toc08
TEMPERATURE (
C)
THRESHOLD (mV)
10
-15
35
60
44
47
46
45
48
49
50
51
52
53
54
-40
10
-15
35
60
85
V
CC
TO RESET DELAY
vs. TEMPERATURE
MAX6715-29 toc09
TEMPERATURE (
C)
V
CC
TO RESET DELAY (
s)
100mV OVERDRIVE
Typical Operating Characteristics
(V
CC
1 = 5V, V
CC
2 = 3.3V, T
A
= +25C, unless otherwise noted.)
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