Maxim MAX6381XS40D6-T Sc70, single/dual low-voltage, low-power î¼p reset circuit Datasheet

19-1839; Rev 1; 04/01
SC70, Single/Dual Low-Voltage,
Low-Power µP Reset Circuits
The MAX6381/MAX6382/MAX6383 are available in 3-pin
SC70 packages and the MAX6384–MAX6390 are available in 4-pin SC70 packages.
________________________Applications
Computers
Controllers
Intelligent Instruments
Critical µP and µC Power Monitoring
Portable/Battery-Powered Equipment
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 VCC = 1V
♦ Manual Reset Input (MAX6384/MAX6385/MAX6386)
♦ Auxiliary RESET IN
(MAX6387/MAX6388/MAX6389)
♦ VCC Reset Timeout (1120ms or 1200ms)/Manual
Reset Timeout (140ms or 150ms) (MAX6390)
♦ Negative-Going VCC 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
Ordering Information
Dual Voltage Systems
Pin Configurations
PART
TEMP. RANGE
PIN-PACKAGE
MAX6381XR_ _D_-T
-40°C to +125°C
3 SC70-3
MAX6382XR_ _D_-T
-40°C to +125°C
3 SC70-3
MAX6383XR_ _D_-T
-40°C to +125°C
3 SC70-3
TOP VIEW
GND 1
RESET
(RESET) 2
MAX6381
MAX6382
MAX6383
3
VCC
SC70
( ) IS FOR MAX6382
Pin Configurations continued at end of data sheet.
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.
________________________________________________________________ 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.
1
MAX6381–MAX6390
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 VCC falls below the factory-set reset
thresholds, the reset output asserts and remains asserted for a minimum reset timeout period after VCC rises
above the reset threshold. Reset thresholds are available
from +1.58V to +4.63V, in approximately 100mV increments. 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 VCC
reset timeout period (1120ms or 1200ms) and a shorter
manual reset timeout (140ms or 150ms).
MAX6381–MAX6390
SC70, Single/Dual Low-Voltage,
Low-Power µP Reset Circuits
ABSOLUTE MAXIMUM RATINGS
VCC to GND ..........................................................-0.3V to +6.0V
RESET Open-Drain Output....................................-0.3V to +6.0V
RESET, RESET (Push-Pull Output) .............-0.3V to (VCC + 0.3V)
MR, RESET IN.............................................-0.3V to (VCC + 0.3V)
Input Current (VCC) .............................................................20mA
Output Current (All Pins) .....................................................20mA
Continuous Power Dissipation (TA = +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
(VCC = full range, TA = -40°C to +125°C, unless otherwise specified. Typical values are at TA = +25°C.) (Note 1)
PARAMETER
Operating Voltage Range
VCC Supply Current
SYMBOL
CONDITIONS
MIN
VCC
ICC
Reset Threshold Tempco
13
6
11
VCC = 2.5V, no load
4
7
3
6
TA = +25°C
VTH 1.5%
VTH
VTH +
1.5%
TA = -40°C to +125°C
VTH 2.5%
VTH
VTH +
2.5%
VCC falling at 10mV/µs from VTH + 100mV
to VTH - 100mV
60
ppm/°C
35
µs
1
20
40
D3
140
280
D5
280
560
D6
560
1120
D4
1120
2240
D7
1200
2400
140
280
tRP
VCC timeout period
D4
D7
150
300
D4
1120
2240
D7
1200
2400
VTH < 4V
VIH
VIL
VIH
2
VTH > 4V
ms
ms
0.3 ✕
VCC
VIL
MR Input Voltage
2
D2
MR timeout period
Reset Timeout Period
MAX6390
µA
V
∆VTH/°C
tRP
V
7
D1
Reset Timeout Period
MAX6381–MAX6389
(See Reset Timeout table)
UNITS
5.5
VCC = 3.6V, no load
VTH
VCC to Reset Delay
MAX
VCC = 5.5V, no load
VCC = 1.8V, no load
VCC Reset Threshold
(See Reset Thresholds table)
TYP
1.0
0.7 ✕
VCC
V
0.8
2.4
_______________________________________________________________________________________
SC70, Single/Dual Low-Voltage,
Low-Power µP Reset Circuits
(VCC = full range, TA = -40°C to +125°C, unless otherwise specified. Typical values are at TA = +25°C.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MR Minimum Input Pulse Width
MIN
TYP
MAX
1
MR Glitch Rejection
µs
100
MR to Reset Delay
ns
200
MR Internal Pullup Resistance
Reset IN Input Threshold
VTHRST
RESET IN Input Leakage Current
Open-Drain RESET Output
Voltage
Open-Drain RESET Output
Leakage Current
32
63
100
kΩ
MAX6390
800
1350
2300
Ω
TA = +25°C
1.245
1.27
1.295
TA = 0°C to +85°C
1.232
1.308
TA = -40°C to +125°C
1.219
1.321
IRESET IN
4.5
-50
VCC ≥ 4.5V, ISINK = 3.2mA, reset asserted
VOL
ILKG
VOL
VOH
µs
+50
VCC ≥ 2.5V, ISINK = 1.2mA, reset asserted
0.3
VCC ≥ 1.0V, ISINK = 80µA, reset asserted
0.3
VCC > VTH, RESET not asserted
1.0
VCC ≥ 4.5V, ISINK = 3.2mA, reset asserted
0.4
VCC ≥ 2.5V, ISINK = 1.2mA, reset asserted
0.3
0.8 ✕
VCC
VCC ≥ 2.5V, ISOURCE = 500µA, reset not
asserted
0.8 ✕
VCC
VCC ≥ 4.5V, ISOURCE = 800µA, reset asserted
0.8 ✕
VCC
VCC ≥ 2.5V, ISOURCE = 500µA, reset asserted
0.8 ✕
VCC
VCC ≥ 1.8V, ISOURCE = 150µA, reset asserted
0.8 ✕
VCC
VCC ≥ 1.0V, ISOURCE = 1µA, reset asserted
0.8 ✕
VCC
Push-Pull RESET Output Voltage
nA
V
µA
0.3
VCC ≥ 4.5V, ISOURCE = 800µA, reset not
asserted
VOH
VOL
±1
V
0.4
VCC ≥ 1.0V, ISINK = 80µA, reset asserted
Push-Pull RESET Output Voltage
ns
MAX6381–MAX6389
VRESETIN falling at 4mV/µs from
VTHRST + 40mV to VTHRST - 40mV
RESET IN to RESET Delay
UNITS
V
V
VCC ≥ 4.5V, ISINK = 3.2mA, reset not
asserted
0.4
VCC ≥ 2.5V, ISINK = 1.2mA, reset not
asserted
0.3
Note 1: Specifications over temperature are guaranteed by design, not production tested.
_______________________________________________________________________________________
3
MAX6381–MAX6390
ELECTRICAL CHARACTERISTICS (continued)
Typical Operating Characteristics
(TA = +25°C, unless otherwise noted.)
5
4
3
VCC = +2.5V
VCC = +1.8V
2
41
1
VCC = +3.0V
39
37
35
VCC = +1.8V
33
31
29
27
0
25
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
-40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
TEMPERATURE (°C)
TEMPERATURE (°C)
NORMALIZED RESET THRESHOLD
vs. TEMPERATURE
OUTPUT VOLTAGE LOW
vs. SINK CURRENT
OUTPUT VOLTAGE HIGH
vs. SOURCE CURRENT
MAX6381/90 toc04
1.2
1.015
1.010
3.0
1.0
VCC = +2.5V
2.5
0.8
1.000
0.995
2.0
VOH (V)
VOL (V)
1.005
0.6
VCC = +3.0V
0.4
VCC = +4.5V
0.2
0
0
3
6
9
12
500
5.5
5.3
5.1
RESET IN DELAY (µs)
400
1000
350
RESET ASSERTED
ABOVE THIS LINE
200
150
MAX6381/90 toc08
450
750
RESET IN TO RESET DELAY
vs. TEMPERATURE
MAX6381/90 toc07
500
MAXIMUM TRANSIENT DURATION (µs)
250
ISOURCE (µA)
MAXIMUM TRANSIENT DURATION
vs. RESET COMPARATOR OVERDRIVE
250
0
ISINK (mA)
TEMPERATURE (°C)
300
VCC = +1.8V
0.5
0
0.990
-40 -25 -10 5 20 35 50 65 80 95 110 125
1.5
1.0
0.990
0.985
4.9
4.7
4.5
4.3
4.1
100
3.9
50
3.7
3.5
0
1
10
100
MAX6381/90 toc06
-40 -25 -10 5 20 35 50 65 80 95 110 125
1.020
1000
RESET COMPARATOR OVERDRIVE, VTH - VCC (mV)
4
1.08
NORMALIZED RESET TIMEOUT PERIOD
VCC = +3.6V
VCC = +5.5V
6
43
MAX6381/90 toc02
7
NORMALIZED POWER-UP RESET TIMEOUT
vs. TEMPERATURE
MAX6381/90 toc05
SUPPLY CURRENT (µA)
8
POWER-DOWN RESET DELAY (µs)
MAX6381/90 toc01
9
POWER-DOWN RESET DELAY
vs. TEMPERATURE
MAX6381/90 toc03
SUPPLY CURRENT vs. TEMPERATURE
(NO LOAD)
NORMALIZED RESET THRESHOLD
MAX6381–MAX6390
SC70, Single/Dual Low-Voltage,
Low-Power µP Reset Circuits
-40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
______________________________________________________________________________________
1250
1500
SC70, Single/Dual Low-Voltage,
Low-Power µP Reset Circuits
PIN
MAX6384/
MAX6381/
MAX6387/
MAX6382 MAX6386/ MAX6385
MAX6388
MAX6389
MAX6383
MAX6390
1
—
2
—
1
2
—
—
1
—
2
3
1
2
—
3
1
—
2
—
1
2
—
—
NAME
GND
FUNCTION
Ground
RESET
Active-High Push-Pull Reset Output. RESET
changes from low to high when any
monitored voltage (VCC or VRESETIN) 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.
RESET
Active-Low Open-Drain/Push-Pull Reset
Output. RESET changes from high to low when
any monitored voltage (VCC or VRESETIN)
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.
MR
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 VCC if unused. MR has an internal
63kΩ (1.35kΩ for MAX6390) pullup resistor to
VCC.
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 VCC or RESET IN falls below its
threshold voltage.
—
—
—
—
3
3
RESET
IN
3
3
4
4
4
4
VCC
Supply Voltage for the device and input for
fixed VCC reset threshold monitor.
_______________________________________________________________________________________
5
MAX6381–MAX6390
Pin Description
MAX6381–MAX6390
SC70, Single/Dual Low-Voltage,
Low-Power µP Reset Circuits
Detailed Description
RESET Output
A µP reset input starts the µP in a known state. These
µP supervisory circuits assert reset to prevent code
execution errors during power-up, power-down, or
brownout conditions.
Reset asserts when VCC is below the reset threshold;
once VCC exceeds the reset threshold, an internal timer
keeps the reset output asserted for the reset timeout
period. After this interval, reset output deasserts. Reset
output is guaranteed to be in the correct logic state for
VCC ≥ 1V.
Manual Reset Input (MAX6384/
MAX6385/MAX6386/MAX6390)
Many µP-based products require manual reset capability, allowing the operator, a test technician, or external
logic circuitry to initiate a reset. A logic low on MR
asserts reset. Reset remains asserted while MR is low,
and for the reset active timeout period (tRP) after MR
returns high. This input has an internal 63kΩ pullup
resistor (1.35kΩ for MAX6390), so it can be left unconnected if it is not used. MR can be driven with TTL or
CMOS logic levels, or with open-drain/collector outputs.
Connect a normally open momentary switch from MR to
GND to create a manual-reset function; external
debounce circuitry is not required. If MR is driven from
long cables or if the device is used in a noisy environment, connecting a 0.1µF capacitor from MR to GND
provides additional noise immunity.
RESET IN Comparator
(MAX6387/MAX6388/MAX6389)
RESET IN is compared to an internal +1.27V reference.
If the voltage at RESET IN is less than 1.27V, reset
asserts. Use the RESET IN comparator as a useradjustable reset detector or as a secondary power-supply monitor by implementing a resistor-divider at RESET
IN (shown in Figure 1). Reset asserts when either VCC
or RESET IN falls below its respective threshold voltage. Use the following equation to set the threshold:
VINTH = VTHRST (R1/R2 + 1)
where VTHRST = +1.27V. To simplify the resistor selection, choose a value of R2 and calculate R1:
R1 = R2 [(VINTH/VTHRST) - 1]
Since the input current at RESET IN is 50nA (max),
large values can be used for R2 with no significant loss
in accuracy.
6
Reset Thresholds (-40°C to +125°C)
SUFFIX
VTH (min)
VTH (nom)
VTH (max)
46
4.51
4.63
4.74
45
4.39
4.50
4.61
44
4.27
4.38
4.48
43
4.19
4.30
4.41
42
4.10
4.20
4.31
41
4.00
4.10
4.20
40
3.90
4.00
4.10
39
3.80
3.90
4.00
38
3.71
3.80
3.90
37
3.61
3.70
3.79
36
3.51
3.60
3.69
35
3.41
3.50
3.59
34
3.32
3.40
3.49
33
3.22
3.30
3.38
32
3.12
3.20
3.28
31
3.00
3.08
3.15
30
2.93
3.00
3.08
29
2.85
2.93
3.00
28
2.73
2.80
2.87
27
2.63
2.70
2.77
26
2.56
2.63
2.69
25
2.44
2.50
2.56
24
2.34
2.40
2.46
23
2.26
2.31
2.37
22
2.13
2.19
2.24
21
2.05
2.10
2.15
20
1.95
2.00
2.05
19
1.85
1.90
1.95
18
1.76
1.80
1.85
17
1.62
1.67
1.71
16
1.54
1.58
1.61
___________Applications Information
Negative-Going VCC Transients
In addition to issuing a reset to the µP during power-up,
power-down, and brownout conditions, the
MAX6381–MAX6390 are relatively immune to short duration negative-going VCC transients (glitches).
The Typical Operating Characteristics section shows the
Maximum Transient Durations vs. Reset Comparator
Overdrive, for which the MAX6381–MAX6390 do not
generate a reset pulse. This graph was generated using
_______________________________________________________________________________________
SC70, Single/Dual Low-Voltage,
Low-Power µP Reset Circuits
VCC
MAX6387
MAX6388
MAX6389
MAX6381
MAX6384
MAX6387
VIN
R1
RESET
(RESET)
RESET IN
R2
RESET
GND
R1
100k
GND
( ) IS FOR MAX6388
Figure 1. RESET IN Configuration
Figure 2. RESET Valid to VCC = Ground Circuit
Reset Timeout Delay
SUFFIX
MIN
D1
1ms
D2
20ms
D3
140ms
D5
280ms
D6
560ms
D4
1120ms
D7
1200ms
MAX6390XSD4
1120/140ms *
MAX6390XSD7
1200/150ms *
* The MAX6390 has a 1120ms or 1200ms RESET timeout and a
140ms or 150ms manual reset timeout
a negative-going pulse applied to VCC, starting above the
actual reset threshold and ending below it by the magnitude indicated (reset comparator overdrive). The graph
indicates the typical maximum pulse width a negativegoing VCC transient may have without causing a reset
pulse to be issued. As the magnitude of the transient
increases (goes farther below the reset threshold), the
maximum allowable pulse width decreases. A 0.1µF
capacitor mounted as close as possible to VCC provides
additional transient immunity.
not work with the open-drain outputs of the
MAX6383/MAX6386/MAX6389/MAX6390. The resistor
value used is not critical, but it must be small enough
not to load the reset output when VCC is above the reset
threshold. For most applications, 100kΩ is adequate.
Standard Versions
PART
RESET TIMEOUT
46
44
31
29
MAX638_
26
D3
23
22
17
16
46
Ensuring a Valid RESET
Output Down to VCC = 0
The MAX6381–MAX6390 are guaranteed to operate
properly down to VCC = 1V. In applications that require
valid reset levels down to VCC = 0, a pulldown resistor to
active-low outputs (push/pull only, Figure 2) and a
pullup resistor to active-high outputs (push/pull only) will
ensure that the reset line is valid while the reset output
can no longer sink or source current. This scheme does
RESET
THRESHOLD
44
31
29
MAX6390
26
D4
23
22
17
16
_______________________________________________________________________________________
7
MAX6381–MAX6390
VCC
MAX6381–MAX6390
SC70, Single/Dual Low-Voltage,
Low-Power µP Reset Circuits
Selector Guide
PART NUMBER
PUSH-PULL
ACTIVE-LOW
MAX6381
X
PUSH-PULL
ACTIVE-HIGH
MAX6382
OPEN-DRAIN
ACTIVE-LOW
MANUAL RESET
INPUT MR
RESET IN
X
MAX6383
X
MAX6384
X
X
MAX6385
X
MAX6386
MAX6390*
MAX6387
X
X
X
X
X
X
X
MAX6388
X
MAX6389
X
X
X
*The MAX6390 offers a VCC reset timeout of 1120ms or 1200ms (min) and a manual reset timeout of 140ms or 150ms (min).
Typical Operating Circuit
Pin Configurations (continued)
I/O SUPPLY
TOP VIEW
VCORE
R1
VCC
GND
RESET IN **
1
CORE
I/O
VOLTAGE VOLTAGE
R1
MAX6381–MAX6390
RESET
(RESET)
MR *
MAX6384
MAX6385
MAX6386
MAX6390
µP
RESET
INPUT
GND
GND
4 VCC
RESET
(RESET)
2
3
MR
4
VCC
3
RESET IN
PUSHBUTTON SWITCH
SC70
( ) IS FOR MAX6385
* MR is for MAX6384/MAX6385/MAX6386/MAX6390
** RESET IN is for MAX6387/MAX6388/MAX6389
( ) are for MAX6382/MAX6385/MAX6388
GND
1
MAX6387
MAX6388
MAX6389
Chip Information
TRANSISTOR COUNT: 647
PROCESS: BiCMOS
RESET
(RESET)
( ) IS FOR MAX6388
8
2
SC70
_______________________________________________________________________________________
SC70, Single/Dual Low-Voltage,
Low-Power µP Reset Circuits
PART
TEMP. RANGE
MAX6384XS_ _D_-T
-40°C to +125°C
4 SC70-4
MAX6385XS_ _D_-T
-40°C to +125°C
4 SC70-4
MAX6386XS_ _D_-T
-40°C to +125°C
4 SC70-4
MAX6387XS_ _D_-T
-40°C to +125°C
4 SC70-4
MAX6388XS_ _D_-T
-40°C to +125°C
4 SC70-4
MAX6381–MAX6390
Ordering Information
(continued)
PIN-PACKAGE
MAX6389XS_ _D_-T
-40°C to +125°C
4 SC70-4
MAX6390XS_ _D_-T*
-40°C to +125°C
4 SC70-4
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.
_______________________________________________________________________________________
9
SC70, Single/Dual Low-Voltage,
Low-Power µP Reset Circuits
SC70, 4L.EPS
MAX6381–MAX6390
Package Information
10
______________________________________________________________________________________
SC70, Single/Dual Low-Voltage,
Low-Power µP Reset Circuits
SC70, 3L.EPS
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 11
© 2001 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.
MAX6381–MAX6390
Package Information (continued)
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