19-1839; Rev 2; 9/04
SC70, Single/Dual Low-Voltage,
Low-Power µP Reset Circuits
General Description
The MAX6381–MAX6390 microprocessor (µP) supervisory
circuits monitor power supply voltages from +1.8V to
+5.0V while consuming only 3µA of supply current at
+1.8V. Whenever V
CC
falls below the factory-set reset
thresholds, the reset output asserts and remains assert-
ed for a minimum reset timeout period after V
CC
rises
above the reset threshold. Reset thresholds are available
from +1.58V to +4.63V, in approximately 100mV incre-
ments. Seven minimum reset timeout delays ranging
from 1ms to 1200ms are available.
The MAX6381/MAX6384/MAX6387 have a push-pull
active-low reset output. The MAX6382/MAX6385/
MAX6388 have a push-pull active-high reset output,
and the MAX6383/MAX6386/MAX6389/MAX6390
have an open-drain active-low reset output. The
MAX6384/MAX6385/MAX6386 also feature a
debounced manual reset input (with internal pullup
resistor). The MAX6387/MAX6388/MAX6389 have an
auxiliary input for monitoring a second voltage. The
MAX6390 offers a manual reset input with a longer V
CC
reset timeout period (1120ms or 1200ms) and a shorter
manual reset timeout (140ms or 150ms).
The MAX6381/MAX6382/MAX6383 are available in 3-pin
SC70 packages and the MAX6384–MAX6390 are avail-
able in 4-pin SC70 packages.
Features
♦
Factory-Set Reset Threshold Voltages Ranging
from +1.58V to +4.63V in Approximately 100mV
Increments
♦
±2.5% Reset Threshold Accuracy Over
Temperature (-40°C to +125°C)
♦
Seven Reset Timeout Periods Available: 1ms,
20ms, 140ms, 280ms, 560ms, 1120ms,
1200ms (min)
♦
3 Reset Output Options
Active-Low Push-Pull
Active-High Push-Pull
Active-Low Open-Drain
♦
Reset Output State Guaranteed Valid
Down to V
CC
= 1V
♦
Manual Reset Input (MAX6384/MAX6385/MAX6386)
♦
Auxiliary RESET IN
(MAX6387/MAX6388/MAX6389)
♦
V
CC
Reset Timeout (1120ms or 1200ms)/Manual
Reset Timeout (140ms or 150ms) (MAX6390)
♦
Negative-Going V
CC
Transient Immunity
♦
Low Power Consumption of 6µA at +3.6V
and 3µA at +1.8V
♦
Pin Compatible with
MAX809/MAX810/MAX803/MAX6326/MAX6327/
MAX6328/MAX6346/MAX6347/MAX6348,
and MAX6711/MAX6712/MAX6713
♦
Tiny 3-Pin SC70 and 4-Pin SC70 Packages
MAX6381–MAX6390
________________________Applications
Computers
Controllers
Intelligent Instruments
Critical µP and µC Power Monitoring
Portable/Battery-Powered Equipment
Dual Voltage Systems
Ordering Information
PART
MAX6381XR_
_D_-T
MAX6382XR_
_D_-T
MAX6383XR_
_D_-T
TEMP RANGE
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
PIN-PACKAGE
3 SC70-3
3 SC70-3
3 SC70-3
Pin Configurations
TOP VIEW
GND
1
RESET
(RESET)
2
MAX6381
MAX6382
MAX6383
3
V
CC
Note:
Insert reset threshold suffix (see Reset Threshold table)
after "XR" or "XS". Insert reset timeout delay (see Reset Timeout
Delay table) after "D" to complete the part number. Sample
stock is generally held on standard versions only (see
Standard Versions table). Standard versions have an order
increment requirement of 2500 pieces. Nonstandard versions
have an order increment requirement of 10,000 pieces.
Contact factory for availability of nonstandard versions.
*MAX6390 is available with D4 or D7 timing only.
Ordering Information continued at end of data sheet.
Typical Operating Circuit appears at end of data sheet.
Selector Guide appears at end of data sheet.
1
SC70
( ) IS FOR MAX6382
Pin Configurations continued at end of data sheet.
________________________________________________________________
Maxim Integrated Products
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.
SC70, Single/Dual Low-Voltage,
Low-Power µP Reset Circuits
MAX6381–MAX6390
ABSOLUTE MAXIMUM RATINGS
V
CC
to GND ..........................................................-0.3V to +6.0V
RESET
Open-Drain Output....................................-0.3V to +6.0V
RESET,
RESET (Push-Pull Output) .............-0.3V to (V
CC
+ 0.3V)
MR,
RESET IN.............................................-0.3V to (V
CC
+ 0.3V)
Input Current (V
CC
) .............................................................20mA
Output Current (All Pins) .....................................................20mA
Continuous Power Dissipation (T
A
= +70°C)
3-Pin SC70 (derate 2.9mW/°C above +70°C) ..............235mW
4-Pin SC70 (derate 3.1mW/°C above +70°C) ..............245mW
Operating Temperature Range .........................-40°C to +125°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
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.
ELECTRICAL CHARACTERISTICS
(V
CC
= full range, T
A
= -40°C to +125°C, unless otherwise specified. Typical values are at T
A
= +25°C.) (Note 1)
PARAMETER
Operating Voltage Range
SYMBOL
V
CC
V
CC
= 5.5V, no load
V
CC
Supply Current
I
CC
V
CC
= 3.6V, no load
V
CC
= 2.5V, no load
V
CC
= 1.8V, no load
V
CC
Reset Threshold
(See Reset Thresholds table)
Reset Threshold Tempco
V
CC
to Reset Delay
T
A
= +25°C
V
TH
T
A
= -40°C to +125°C
∆V
TH
/°C
V
CC
falling at 10mV/µs from V
TH
+ 100mV
to V
TH
- 100mV
D1
D2
Reset Timeout Period
MAX6381–MAX6389
(See Reset Timeout table)
D3
t
RP
D5
D6
D4
D7
MR
timeout period
Reset Timeout Period
MAX6390
t
RP
V
CC
timeout period
V
IL
V
TH
< 4V
MR
Input Voltage
V
IH
V
IL
V
IH
V
TH
> 4V
0.7 x
V
CC
0.8
2.4
D4
D7
D4
D7
1
20
140
280
560
1120
1200
140
150
1120
1200
V
TH
-
1.5%
V
TH
-
2.5%
CONDITIONS
MIN
1.0
7
6
4
3
V
TH
V
TH
60
35
2
40
280
560
1120
2240
2400
280
300
2240
2400
0.3 x
V
CC
V
ms
ms
TYP
MAX
5.5
13
11
7
6
V
TH
+
1.5%
V
V
TH
+
2.5%
ppm/°C
µs
µA
UNITS
V
2
_______________________________________________________________________________________
SC70, Single/Dual Low-Voltage,
Low-Power µP Reset Circuits
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= full range, T
A
= -40°C to +125°C, unless otherwise specified. Typical values are at T
A
= +25°C.) (Note 1)
PARAMETER
MR
Minimum Input Pulse Width
MR
Glitch Rejection
MR
to Reset Delay
MR
Internal Pullup Resistance
MAX6381–MAX6389
MAX6390
T
A
= +25°C
RESET IN Input Threshold
V
THRST
T
A
= 0°C to +85°C
T
A
= -40°C to +125°C
RESET IN to RESET Delay
RESET IN Input Leakage Current
Open-Drain
RESET
Output
Voltage
Open-Drain
RESET
Output
Leakage Current
I
RESET IN
V
CC
≥
4.5V, I
SINK
= 3.2mA, reset asserted
V
OL
V
CC
≥
2.5V, I
SINK
= 1.2mA, reset asserted
V
CC
≥
1.0V, I
SINK
= 80µA, reset asserted
I
LKG
V
CC
> V
TH
,
RESET
not asserted
V
CC
≥
4.5V, I
SINK
= 3.2mA, reset asserted
V
OL
Push-Pull
RESET
Output Voltage
V
OH
V
CC
≥
2.5V, I
SINK
= 1.2mA, reset asserted
V
CC
≥
1.0V, I
SINK
= 80µA, reset asserted
V
CC
≥
4.5V, I
SOURCE
= 800µA, reset not
asserted
V
CC
≥
2.5V, I
SOURCE
= 500µA, reset not
asserted
V
CC
≥
4.5V, I
SOURCE
= 800µA, reset asserted
V
CC
≥
2.5V, I
SOURCE
= 500µA, reset asserted
V
OH
V
CC
≥
1.8V, I
SOURCE
= 150µA, reset asserted
Push-Pull RESET Output Voltage
V
CC
≥
1.0V, I
SOURCE
= 1µA, reset asserted
V
CC
≥
4.5V, I
SINK
= 3.2mA, reset not
asserted
V
OL
V
CC
≥
2.5V, I
SINK
= 1.2mA, reset not
asserted
0.8 x
V
CC
0.8 x
V
CC
0.8 x
V
CC
0.8 x
V
CC
0.8 x
V
CC
0.8 x
V
CC
0.4
0.3
V
RESETIN
falling at 4mV/µs from
V
THRST
+ 40mV to V
THRST
- 40mV
-50
32
500
1.245
1.232
1.219
4.5
±1
+50
0.4
0.3
0.3
1.0
0.4
0.3
0.3
V
µA
V
SYMBOL
CONDITIONS
MIN
1
100
200
63
1560
1.27
100
3000
1.295
1.308
1.321
µs
nA
V
TYP
MAX
UNITS
µs
ns
ns
kΩ
Ω
MAX6381–MAX6390
V
Note 1:
Specifications over temperature are guaranteed by design, not production tested.
_______________________________________________________________________________________
3
SC70, Single/Dual Low-Voltage,
Low-Power µP Reset Circuits
MAX6381–MAX6390
Typical Operating Characteristics
(T
A
= +25°C, unless otherwise noted.)
SUPPLY CURRENT vs. TEMPERATURE
(NO LOAD)
MAX6381/90 toc01
POWER-DOWN RESET DELAY
vs. TEMPERATURE
NORMALIZED RESET TIMEOUT PERIOD
41
POWER-DOWN RESET DELAY (µs)
39
37
35
33
31
29
27
25
V
CC
= +1.8V
MAX6381/90 toc02
NORMALIZED POWER-UP RESET TIMEOUT
vs. TEMPERATURE
MAX6381/90 toc03
9
8
SUPPLY CURRENT (µA)
7
6
5
4
3
2
1
0
V
CC
= +2.5V
V
CC
= +1.8V
V
CC
= +5.5V
V
CC
= +3.6V
43
V
CC
= +3V
1.08
1.06
1.04
1.02
1.00
0.98
0.96
0.94
-40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
-40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
-40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
NORMALIZED RESET THRESHOLD
vs. TEMPERATURE
MAX6381/90 toc04
OUTPUT VOLTAGE LOW
vs. SINK CURRENT
MAX6381/90 toc05
OUTPUT VOLTAGE HIGH
vs. SOURCE CURRENT
V
CC
= +2.5V
2.5
2.0
V
OH
(V)
1.5
1.0
V
CC
= +1.8V
MAX6381/90 toc06
1.020
NORMALIZED RESET THRESHOLD
1.015
1.010
1.005
1.000
0.995
0.990
0.985
1.2
1.0
0.8
V
OL
(V)
0.6
V
CC
= +3.0V
0.4
0.2
0
0
3
6
I
SINK
(mA)
9
V
CC
= +4.5V
3.0
0.5
0
12
0
250
500
750
1000
1250
1500
I
SOURCE
(µA)
0.990
-40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
MAXIMUM TRANSIENT DURATION
vs. RESET COMPARATOR OVERDRIVE
MAX6381/90 toc07
RESET IN TO RESET DELAY
vs. TEMPERATURE
5.3
5.1
RESET IN DELAY (µs)
4.9
4.7
4.5
4.3
4.1
3.9
3.7
3.5
MAX6381/90 toc08
500
MAXIMUM TRANSIENT DURATION (µs)
450
400
350
300
250
200
150
100
50
0
1
10
100
RESET ASSERTED
ABOVE THIS LINE
5.5
1000
-40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
RESET COMPARATOR OVERDRIVE, V
TH
- V
CC
(mV)
4
______________________________________________________________________________________
SC70, Single/Dual Low-Voltage,
Low-Power µP Reset Circuits
Pin Description
PIN
MAX6384/
MAX6381/
MAX6387/
MAX6382 MAX6386/ MAX6385
MAX6388
MAX689
MAX6383
MAX6390
1
1
1
1
1
1
NAME
FUNCTION
MAX6381–MAX6390
GND
Ground
Active-High Push-Pull Reset Output. RESET
changes from low to high when any
monitored voltage (V
CC
or V
RESETIN
) drops
below the reset threshold or
MR
is pulled low.
RESET remains high for the reset timeout
period after monitored voltages exceed the
reset thresholds or
MR
is released.
Active-Low Open-Drain/Push-Pull Reset
Output.
RESET
changes from high to low when
any monitored voltage (V
CC
or V
RESETIN
)
drops below the reset threshold or
MR
is
pulled low.
RESET
remains low for the reset
timeout period after the monitored voltages
exceed the reset thresholds or
MR
is released.
Open-drain requires an external pullup
resistor.
Active-Low Manual Reset Input. Drive low to
force a reset. Reset remains active as long
as
MR
is low and for the reset timeout period
after
MR
is released. Leave unconnected or
connect to V
CC
if unused.
MR
has an internal
63kΩ (1.56kΩ for MAX6390) pullup resistor to
V
CC
.
Auxiliary Reset Input. High-impedance input
to the auxiliary reset comparator. Connect
RESET IN to the center point of an external
resistor voltage-divider network to set the
reset threshold voltage. Reset asserts when
either V
CC
or RESET IN falls below its
threshold voltage.
Supply Voltage for the device and input for
fixed V
CC
reset threshold monitor.
—
2
—
2
—
2
RESET
2
—
2
—
2
—
RESET
—
—
3
3
—
—
MR
—
—
—
—
3
3
RESET
IN
3
3
4
4
4
4
V
CC
_______________________________________________________________________________________
5
Microchip MCU
