19-1623; Rev 0; 1/00
4-Pin SC70 Microprocessor Reset Circuits
with Manual Reset Input
General Description
The MAX6711/MAX6712/MAX6713 are microprocessor
(µP) supervisory circuits used to monitor the power
supplies in µP and digital systems. They provide excel-
lent circuit reliability and low cost by eliminating exter-
nal components and adjustments when used with
+5.0V, +3.3V, +3.0V, or +2.5V-powered circuits. They
also provide a debounced manual reset input.
These circuits assert a reset signal whenever the V
CC
supply voltage declines below a preset threshold or
whenever manual reset is asserted. Reset remains
asserted for at least 140ms after V
CC
has risen above
the reset threshold or when manual reset is deasserted.
Reset thresholds suitable for operation with a variety of
supply voltages are available.
The MAX6713 has an open-drain output stage, while
the MAX6711/MAX6712 have push-pull outputs. The
MAX6713’s open-drain
RESET
output requires a pull-up
resistor that can be connected to a voltage higher than
V
CC
. The MAX6711/MAX6713 have an active-low reset
output, while the MAX6712 has an active-high reset out-
put. The reset comparator is designed to ignore fast
transients on V
CC
, and the outputs are guaranteed to
be in the correct logic state for V
CC
down to 1V.
Low supply current makes the MAX6711/MAX6712/
MAX6713 ideal for use in portable equipment. These
devices are available in a 4-pin SC70 package.
____________________________Features
o
Precision Monitoring of 2.5V, 3.0V, 3.3V, and 5.0V
Power-Supply Voltages
o
Fully Specified Over Temperature
o
Available in Three Output Configurations
Push-Pull
RESET
Output (MAX6711)
Push-Pull RESET Output (MAX6712)
Open-Drain
RESET
Output (MAX6713)
o
140ms min Power-On Reset Pulse Width
o
Manual Reset Input
o
12µA Supply Current
o
Guaranteed Reset Valid to V
CC
= +1V
o
Power-Supply Transient Immunity
o
No External Components
o
4-Pin SC70 Package
MAX6711L/M/R/S/T/Z, MAX6712L/M/R/S/T/Z, MAX6713L/M/R/S/T/Z
Ordering Information
PART
TEMP. RANGE
PIN-PACKAGE
MAX6711_EXS-T
-40°C to +125°C
4 SC70-4
MAX6711_EXS-T10
-40°C to +125°C
4 SC70-4
MAX6712_EXS-T
-40°C to +125°C
4 SC70-4
MAX6712_EXS-T10
-40°C to +125°C
4 SC70-4
MAX6713_EXS-T
-40°C to +125°C
4 SC70-4
MAX6713_EXS-T10
-40°C to +125°C
4 SC70-4
Note:
These parts are offered in 2.5k or 10k reels and must be
ordered in 2.5k or 10k increments. Order MAX6711_EXS-T for
2.5k reels and MAX6711_EXS-T10 for 10k reels. Insert the
desired suffix letter from the Selector Guide into the blank to
complete the part number.
Selector Guide appears at end of data sheet.
Applications
Computers
Controllers
Intelligent Instruments
Critical µP and µC Power Monitoring
Portable/Battery-Powered Equipment
Automotive
Typical Operating Circuit
V
CC
V
CC
R
PULL-UP
*
V
CC
Pin Configuration
TOP VIEW
GND
1
4
V
CC
MAX6711
MAX6713
PUSHBUTTON
MR
SWITCH
GND
RESET
RESET
INPUT
µP
MAX6711
MAX6712
MAX6713
RESET (RESET)
2
GND
3
MR
*MAX6713 ONLY
( ) ARE FOR MAX6712.
SC70-4
________________________________________________________________
Maxim Integrated Products
1
For free samples and the latest literature: www.maxim-ic.com, or phone 1-800-998-8800.
For small orders, phone 1-800-835-8769.
4-Pin SC70 Microprocessor Reset Circuits
with Manual Reset Input
MAX6711L/M/R/S/T/Z, MAX6712L/M/R/S/T/Z, MAX6713L/M/R/S/T/Z
ABSOLUTE MAXIMUM RATINGS
Terminal Voltage (with respect to GND)
V
CC
........................................................................-0.3V to +6.0V
RESET,
RESET
(push-pull) .........................-0.3V to (V
CC
+ 0.3V)
RESET
(open drain)...............................................-0.3V to +6.0V
MR
..............................................................-0.3V to (V
CC
+ 0.3V)
Input Current, V
CC
,
MR
.......................................................20mA
Output Current, RESET,
RESET
..........................................20mA
Rate of Rise, V
CC
............................................................100V/µs
Continuous Power Dissipation (T
A
= +70°C)
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 noted. Typical values are at V
CC
= +5V for L/M versions, V
CC
= +3.3V for
T/S versions, V
CC
= +3V for R version, V
CC
= +2.5V for Z version, and T
A
= +25°C.) (Note 1)
PARAMETER
V
CC
Range
SYMBOL
CONDITIONS
T
A
= 0°C to +70°C
T
A
= -40°C to +125°C
T
A
= -40°C to
+85°C
Supply Current
I
CC
T
A
= +85°C to
+125°C
MAX671_L
V
CC
< 5.5V, MAX671_L/M
V
CC
< 3.6V, MAX671_R/S/T/Z
V
CC
< 5.5V, MAX671_L/M
V
CC
< 3.6V, MAX671_R/S/T/Z
T
A
= +25°C
T
A
= -40°C to +85°C
T
A
= +85°C to +125°C
T
A
= +25°C
MAX671_M
T
A
= -40°C to +85°C
T
A
= +85°C to +125°C
T
A
= +25°C
MAX671_T
Reset Threshold
V
TH
MAX671_S
T
A
= -40°C to +85°C
T
A
= +85°C to +125°C
T
A
= +25°C
T
A
= -40°C to +85°C
T
A
= +85°C to +125°C
T
A
= +25°C
MAX671_R
T
A
= -40°C to +85°C
T
A
= +85°C to +125°C
T
A
= +25°C
MAX671_Z
Reset Threshold Tempco
V
CC
to Reset Delay (Note 2)
Reset Active Timeout Period
V
CC
= V
TH
to (V
TH
- 100mV)
T
A
= -40°C to +85°C
T
A
= +85°C to +125°C
140
100
T
A
= -40°C to +85°C
T
A
= +85°C to +125°C
4.56
4.50
4.44
4.31
4.25
4.20
3.04
3.00
2.95
2.89
2.85
2.81
2.59
2.55
2.52
2.28
2.25
2.22
30
20
240
460
640
2.32
2.63
2.93
3.08
4.38
4.63
MIN
1.0
1.2
16
12
TYP
MAX
5.5
5.5
35
30
60
60
4.70
4.75
4.82
4.45
4.50
4.56
3.11
3.15
3.21
2.96
3.00
3.05
2.66
2.70
2.74
2.35
2.38
2.42
ppm/°C
µs
ms
V
µA
UNITS
V
2
_______________________________________________________________________________________
4-Pin SC70 Microprocessor Reset Circuits
with Manual Reset Input
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= full range, T
A
= -40°C to +125°C, unless otherwise noted. Typical values are at V
CC
= +5V for L/M versions, V
CC
= +3.3V for
T/S versions, V
CC
= +3V for R version, V
CC
= +2.5V for Z version, and T
A
= +25°C.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
V
CC
= V
TH
min, I
SINK
= 1.2mA,
MAX6711R/S/T/Z, MAX6713R/S/T/Z
RESET
Output Voltage Low
(MAX6711/MAX6713)
V
OL
V
CC
= V
TH
min, I
SINK
= 3.2mA,
MAX6711L/M, MAX6713L/M
V
CC
> 1.0V, I
SINK
= 50µA
RESET
Output Voltage High
(MAX6711)
V
CC
> V
TH
max, I
SOURCE
= 500µA,
MAX6711R/S/T/Z
V
OH
V
CC
> V
TH
max, I
SOURCE
= 800µA,
MAX6711L/M
V
CC
= V
TH
max, I
SINK
= 1.2mA,
MAX6712R/S/T/Z
V
OL
V
CC
= V
TH
max, I
SINK
= 3.2mA,
MAX6712L/M
1.8V < V
CC
< V
TH
min, I
SOURCE
= 150µA
V
CC
> V
TH
,
RESET
deasserted
V
IL
V
IH
10
1
100
200
20
0.3
·
V
CC
0.7
·
V
CC
0.8
·
V
CC
1
0.8
·
V
CC
V
0.8
·
V
CC
0.3
V
0.4
V
µA
V
kΩ
µs
ns
ns
MIN
TYP
MAX
0.3
0.4
0.3
V
UNITS
MAX6711L/M/R/S/T/Z, MAX6712L/M/R/S/T/Z, MAX6713L/M/R/S/T/Z
RESET Output Voltage Low
(MAX6712)
RESET Output Voltage High
(MAX6712)
RESET
Open-Drain Output
Leakage Current
MR
Input Threshold
MR
Pull-Up Resistance
MR
Minimum Pulse Width
MR
Glitch Immunity
MR
to Reset Delay
V
OH
Note 1:
Production testing done at T
A
= +25°C; limits over temperature guaranteed by design only.
Note 2:
RESET
output for MAX6711/MAX6713; RESET output for MAX6712.
_______________________________________________________________________________________
3
4-Pin SC70 Microprocessor Reset Circuits
with Manual Reset Input
MAX6711L/M/R/S/T/Z, MAX6712L/M/R/S/T/Z, MAX6713L/M/R/S/T/Z
Typical Operating Characteristics
(V
CC
= full range, T
A
= -40°C to +125°C, unless otherwise noted. Typical values are at V
CC
= +5V for L/M versions, V
CC
= +3.3V for
T/S versions, V
CC
= +3V for R version, V
CC
= +2.5V for Z version, and T
A
= +25°C.)
SUPPLY CURRENT vs. TEMPERATURE
(NO LOAD)
MAX6711/12/13 toc01
MAX671_R/S/T/Z
POWER-DOWN RESET DELAY vs. TEMPERATURE
MAX6711/12/13-TOC2
MAX671_L/M
POWER-DOWN RESET DELAY vs. TEMPERATURE
V
OD
= 10mV
POWER-DOWN RESET DELAY (µs)
150
120
V
OD
= 20mV
90
60
30
0
-40 -20
V
OD
= 100mV
V
OD
= 200mV
0
20 40 60 80
TEMPERATURE (°C)
100 120
MAX6711/12/13-TOC3
15
80
V
OD
= 10mV
POWER-DOWN RESET DELAY (µs)
60
V
OD
= 20mV
40
180
MAX671_L/M, V
CC
= 5V
SUPPLY CURRENT (µA)
10
MAX671 _Z, V
CC
= 2.5V
MAX671 _R/S/T, V
CC
= 3.3V
5
MAX671 _L/M/R/S/T/Z, V
CC
= 1V
0
-40 -20
0
20
40
60
80
100 120
TEMPERATURE (°C)
20
V
OD
= 100mV
V
OD
= 200mV
0
20
40
60
80
100 120
0
-40 -20
TEMPERATURE (°C)
POWER-UP RESET TIMEOUT vs.
TEMPERATURE
MAX6711/12/13-TOC4
RESET THRESHOLD vs. TEMPERATURE
V
TH
= 4.63V
MAX6711/12/13-TOC5
300
POWER-UP RESET TIMEOUT (ms)
1.001
RESET THRESHOLD (V)
275
MAX671_ R/S/T/Z
250
1.000
0.999
225
MAX671_ L/M
200
-40 -20
0
20
40
60
80
100 120
TEMPERATURE (°C)
0.998
-40 -20
0
20
40
60
80
100 120
TEMPERATURE (°C)
4
_______________________________________________________________________________________
4-Pin SC70 Microprocessor Reset Circuits
with Manual Reset Input
_____________________Pin Description
PIN
1
NAME
GND
RESET
(MAX6711/
MAX6713)
2
RESET
(MAX6712)
Ground
RESET
Output remains low while V
CC
is below the reset threshold, and for at
least 140ms after V
CC
rises above the
reset threshold.
RESET Output remains high while V
CC
is below the reset threshold, and for at
least 140ms after V
CC
rises above the
reset threshold.
Manual Reset Input. RESET (RESET)
remains asserted as long as
MR
is low,
and for at least 140ms after
MR
is
deasserted. This active-low input has
an internal 20kΩ (typ) pull-up resistor.
It can be driven from a TTL- or CMOS-
logic line, or shorted to ground with a
switch. Leave open or connect to V
CC
if unused.
Supply Voltage (+5.0V, +3.3V, +3.0V,
or +2.5V)
MAX6711
RESET
MR
GND
R1
100k
MAX6711L/M/R/S/T/Z, MAX6712L/M/R/S/T/Z, MAX6713L/M/R/S/T/Z
FUNCTION
V
CC
Figure 2.
RESET
Valid to V
CC
= Ground Circuit
3
MR
least 140ms after V
CC
has risen above the reset thresh-
old. The MAX6713 uses an open-drain output, and the
MAX6711/MAX6712 have a push-pull output stage.
Connect a pull-up resistor on the MAX6713’s
RESET
output to any supply between 0 and 6V.
Manual Reset Input
Many µP-based systems require manual reset capabili-
ty, allowing the operator, a test technician, or external
logic circuitry to initiate a reset. Reset remains asserted
while
MR
is low, and for at least 140ms after
MR
returns
high. This input has an internal 20kΩ pull-up resistor, so
it can be left open if it is not used.
MR
can be driven
with TTL- or CMOS-logic levels, or with open-drain/col-
lector outputs. To create a manual reset function, con-
nect a normally open momentary switch from
MR
to
ground; 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 ground provides additional noise immunity.
4
V
CC
400
MAXIMUM TRANSIENT DURATION (µs)
T
A
= +25°C
320
240
160
MAX671_L/M
80
MAX671_R/S/T/Z
0
1
10
100
1000
RESET COMPARATOR OVERDRIVE, V
TH
- V
CC
(mV)
Applications Information
Negative-Going V
CC
Transients
In addition to issuing a reset to the µP during power-up,
power-down, and brownout conditions, the MAX6711/
MAX6712/MAX6713 are relatively immune to short-dura-
tion negative-going V
CC
transients (glitches).
Figure 1 shows typical transient duration vs. reset com-
parator overdrive, for which the MAX6711/MAX6712/
MAX6713 do
not
generate a reset pulse. The graph was
generated using a negative-going pulse applied to V
CC
,
starting 0.5V above the actual reset threshold and end-
ing below it by the magnitude indicated (reset compara-
tor overdrive). The graph indicates the maximum pulse
width a negative-going V
CC
transient can have without
causing a reset pulse. As the magnitude of the transient
increases (goes farther below the reset threshold), the
5
Figure 1. Maximum Transient Duration Without Causing a
Reset Pulse vs. Reset Comparator Overdrive
Detailed Description
Reset Output
A microprocessor’s (µP’s) reset input starts the µP in a
known state. The MAX6711/MAX6712/MAX6713 assert
reset to prevent code-execution errors during power-
up, power-down, or brownout conditions. They assert a
reset signal whenever the V
CC
supply voltage declines
below a preset threshold, keeping it asserted for at
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