19-2690; Rev 3; 5/14
General Description
The MAX700/MAX701/MAX702 are supervisory circuits
used to monitor the power supplies in microprocessor
(µP) and digital systems. The RESET/RESET outputs of
the MAX700/MAX701/MAX702 are guaranteed to be in
the correct state for VCC voltages down to +1V (Figure 4).
They provide excellent circuit reliability and low cost by
eliminating external components and adjustments when
used with +5V-powered circuits.
The MAX702 is the simplest part in the family. When
VCC falls to 4.65V, RESET goes low. The MAX702 also
provides a debounced manual-reset input. The MAX701
performs the same functions but has both RESET and
RESET outputs. Their primary function is to provide a
system reset. Accordingly, an active reset signal is
supplied for low supply voltages and for at least 200ms
after the supply voltage reaches its operating value.
In addition to the features of the MAX701 and MAX702,
the MAX700 provides preset or adjustable-voltage
detection so thresholds other than 4.65V can be select-
ed, and adjustable hysteresis. All parts are supplied in
8-pin PDIP and narrow-SO packages in commercial and
extended temperature ranges.
Applications
●Computers
●Controllers
●Intelligent Instruments
●Critical µP Power Monitoring
Features
●Min 200ms RESET Pulse on Power-Up, Power-
Down, and During Low-Voltage Conditions
●Reset Threshold Factory Trimmed for +5V Systems
●No External Components or Adjustments with
+5V-Powered Circuits
●Debounced Manual-Reset Input
●Preset or Adjustable-Voltage Detection (MAX700)
●Adjustable Hysteresis (MAX700)
●8-Pin PDIP and Narrow-SO Packages
*Devices in PDIP and SO packages are available in both lead-
ed and lead(Pb)-free packaging. Specify lead free by adding
the + symbol at the end of the part number when ordering.
PART* TEMP RANGE PIN-PACKAGE
MAX700C/D 0°C to +70°C Dice
MAX700CPA 0°C to +70°C 8 PDIP
MAX700CSA 0°C to +70°C 8 Narrow SO
MAX700EPA -40°C to +85°C 8 PDIP
MAX700ESA -40°C to +85°C 8 Narrow SO
MAX701C/D 0°C to +70°C Dice
MAX701CPA 0°C to +70°C 8 PDIP
MAX701CSA 0°C to +70°C 8 Narrow SO
MAX701EPA -40°C to +85°C 8 PDIP
MAX701ESA -40°C to +85°C 8 Narrow SO
MAX702C/D 0°C to +70°C Dice
MAX702CPA 0°C to +70°C 8 PDIP
MAX702CSA 0°C to +70°C 8 Narrow SO
MAX702EPA -40°C to +85°C 8 PDIP
MAX702ESA -40°C to +85°C 8 Narrow SO
RESET
RESETGND
1
2
8
7
VCC
CTLSENSE
HYST
MR
DIP/SO
TOP VIEW
3
4
6
5
MAX700
RESET
RESET
GND
1
2
8
7
VCC
N.C.N.C.
N.C.
MR
DIP/SO
3
4
6
5
MAX701
N.C.
N.C.
RESET
GND
1
2
8
7
N.C.
VCC
N.C.
MR
DIP/SO
3
4
6
5
MAX702
MAX700/MAX701/MAX702 Power-Supply Monitor with Reset
Pin Congurations
Ordering Information
VCC .....................................................................-0.3V to +15.5V
Voltage (with respect to GND) at RESET, RESET,
HYST, CTL, SENSE ........................................... -0.3V to VCC
Operating Temperature Range
C Suffix ...............................................................0°C to +70°C
E Suffix ........................................................... -40°C to +85°C
Rate of Rise, VCC ..........................................................100V/µs
Power Dissipation, Any Package ....................................380mW
Storage Temperature Range ............................ -55°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
(VCC = +5V, CTL = GND on MAX700, TA = +25°C, unless otherwise noted.)
PARAMETER CONDITIONS MIN TYP MAX UNITS
VCC Monitor Voltage Range
(MAX700 Only) TA = TMIN to TMAX, CTL = VCC 3 15 V
Min VCC for Valid Reset Output,
Declining Supply TA = TMIN to TMAX, VRESET ≤ 0.4V when sinking 1mA 1.5 1 V
Supply Current 100 200 µA
Reset Threshold TA = TMIN to TMAX
Power-up 4.50 4.65 4.75 V
Power-down 4.50 4.62 4.75
Internal Hysteresis HYST not connected 30 mV
Reset Output Pulse Width 200 350 500 ms
RESET Fall Time MAX700/MAX701 only, CLOAD = 100pF 200 ns
VCC Pulse Duration
Guaranteeing 5V to 4V VCC pulse No reset 10 1 µs
Reset 100 10
MR Input Threshold 0.7 V
MR Pullup Current -5 -30 µA
MAX700
RESET Output Low ISINK = 3.2mA, VCC = 5V 0.4 V
ISINK = 1.6mA, VCC = 3V 0.4
RESET Output High
ISOURCE = 3.2mA, VCC = 4.25V VCC - 0.4
VISOURCE = 1.6mA, VCC = 3V VCC - 0.4
ISOURCE = 0.5mA, VCC = 1.5V VCC - 0.4
RESET Output Low
ISINK = 16mA, VCC = 4.25V 0.4
VISINK = 1.6mA, VCC = 3V 0.4
ISINK = 0.4mA, VCC = 1.5V 0.4
RESET Output High ISOURCE = 3.2mA, VCC = 5V VCC - 0.4 V
ISOURCE = 1.6mA, VCC = 3V VCC - 0.4
MAX700/MAX701/MAX702 Power-Supply Monitor with Reset
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Absolute Maximum Ratings
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 = +5V, CTL = GND on MAX700, TA = +25°C, unless otherwise noted.)
PARAMETER CONDITIONS MIN TYP MAX UNITS
MAX701
RESET Output Low ISINK = 16mA, VCC = 5V 0.4 V
RESET Output High
ISOURCE = 3.2mA, VCC = 4.25V VCC - 0.4
VISOURCE = 1.6mA, VCC = 3V VCC - 0.4
ISOURCE = 0.5mA, VCC = 1.5V VCC - 0.4
RESET Output Low
ISINK = 3.2mA, VCC = 4.25V 0.4
VISINK = 1.6mA, VCC = 3V 0.4
ISINK = 0.4mA, VCC = 1.5V 0.4
RESET Output High ISOURCE = 3.2mA, VCC = 5V VCC - 0.4 V
MAX702
RESET Output Low
ISINK = 3.2mA, VCC = 4.25V 0.4
VISINK = 1.6mA, VCC = 3V 0.4
ISINK = 0.4mA, VCC = 1.5V 0.4
RESET Output High ISOURCE = 3.2mA, VCC = 5V VCC - 0.4 V
MAX700 ONLY (CTL = VCC, unless otherwise noted)
SENSE Input Threshold TA = TMIN to TMAX 1.25 1.29 1.35 V
SENSE Input Current 0.1 nA
HYST Input On-Resistance 0.5 kΩ
CTL Input Threshold 2 V
CTL Pulldown Current 30 100 µA
MAX700/MAX701/MAX702 Power-Supply Monitor with Reset
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Electrical Characteristics (continued)
PIN NAME FUNCTION
MAX700 MAX701 MAX702
1 1 1 MR Input for Manual Pushbutton Reset. Has internal 5µA pullup. Low input activates the
RESET/RESET outputs.
2 — — SENSE
The voltage-sense input when CTL = VCC. Its threshold is 1.29V. SENSE always
remains connected to the internal comparator. So, when VCC is being monitored
internally (CTL = GND), SENSE should be left open circuit.
3 — — HYST
Normally NOT used when voltage is monitored through VCC (CTL = GND). When
monitoring through SENSE (CTL = VCC), HYST allows hysteresis to be added,
reducing noise and spurious reset activity (Figure 3). HYST turns on 5µs before the
RESET/RESET outputs are activated, and its on-resistance to GND is typically 1kΩ.
4 4 3 GND Ground
5 6 7 RESET Goes low when VCC falls below 4.65V, or when CTL = VCC on the MAX700 goes low
when SENSE falls below 1.29V.
6 5 — RESET Inverted Version of RESET
7 — — CTL
When CTL = GND, VCC is monitored by the reset circuit. When CTL = VCC, VCC
is ignored and SENSE is monitored, allowing the threshold to be set with external
resistors.
8 8 2 VCC Chip Power and +5V Sensing Input (When CTL = GND on MAX700)
— 2, 3, 7 4, 5, 6, 8 N.C. No Connection
MAX700/MAX701/MAX702 Power-Supply Monitor with Reset
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Pin Description
Figure 4 shows the RESET output of the MAX700/
MAX701/MAX702 in the correct state for VCC voltages
down to 0V. Note the effect of the built-in hysteresis on
the trigger lever of RESET.
Figure 1. MAX700 Block Diagram
Figure 3. MAX700 Connected for External Senses and
Hysteresis
Figure 2. MAX700 Typical Connection Diagram
Figure 4. Typical MAX700/MAX701/MAX702 RESET Output vs.
VCC
PACKAGE
TYPE
PACKAGE
CODE
OUTLINE
NO.
LAND
PATTERN NO.
8 PDIP P8+2 21-0143 —
8 Narrow SO S8+4 21-0041 90-0096
RESET
1M
1.29VREF
OSC
RC
R
R
COMPARATOR
RESET
GND
1
2
8
7
VCC
CTL
SENSE
HYST
150k
MR
3
4
6
5
MAX700
GND
1
2
8
7
SENSE
MANUAL
RESET
BUTTON
HYST
MR
3
4
6N.C.
R1
R3R2
VIN
TO µP
VIN 3V TO 15V
VL = LOWER VOLTAGE THRESHOLDR1 = R2 ( VL - 1)
1.29
R3 = VTR1
VU - VLVU = UPPER VOLTAGE THRESHOLD
HYSTERESIS = VU - VL
5
MAX700
RESET
RESET
VCC
CTL
GND
1
2
8
7
SENSE
MANUAL
RESET
BUTTON
HYST
MR
3
4
6N.C.
N.C.
TO µP
+5V
5
MAX700
RESET
RESET
VCC
CTL
RESET
0V
0V
2V/div
2V/div
1s/div
VCC
MAX700/MAX701/MAX702 Power-Supply Monitor with Reset
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Package Information
For the latest package outline information and land patterns
(footprints), go to www.maximintegrated.com/packages. Note
that a “+”, “#”, or “-” in the package code indicates RoHS status
only. Package drawings may show a different suffix character, but
the drawing pertains to the package regardless of RoHS status.
REVISION
NUMBER
REVISION
DATE DESCRIPTION PAGES
CHANGED
0 3/90 Initial release —
1 11/05 Added lead-free information to the Ordering Information table. 1
2 12/07 Updated Pin Description table. 4
3 5/14 No /V OPNs; removed automotive reference from Applications section 1
Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent licenses
are implied. Maxim Integrated reserves the right to change the circuitry and specications without notice at any time. The parametric values (min and max limits)
shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance.
Maxim Integrated and the Maxim Integrated logo are trademarks of Maxim Integrated Products, Inc.
Power-Supply Monitor with Reset
© 2014 Maxim Integrated Products, Inc.
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MAX700/MAX701/MAX702
Revision History
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