MAXIM MAX708EPA

19-4334; Rev. 5; 9/95
Low-Cost, µP Supervisory Circuits
The MAX705-MAX708/MAX813L microprocessor (µP)
supervisory circuits reduce the complexity and number
of components required to monitor power-supply and
battery functions in µP systems. These devices significantly improve system reliability and accuracy compared to separate ICs or discrete components.
The MAX705/MAX706/MAX813L provide four functions:
1) A reset output during power-up, power-down, and
brownout conditions.
2) An independent watchdog output that goes low if
the watchdog input has not been toggled within 1.6
seconds.
3) A 1.25V threshold detector for power-fail warning,
low-battery detection, or for monitoring a power supply other than +5V.
4) An active-low manual-reset input.
The MAX707/MAX708 are the same as the MAX705/
MAX706, except an active-high reset is substituted for
the watchdog timer. The MAX813L is the same as the
MAX705, except RESET is provided instead of RESET.
Two supply-voltage monitor levels are available: The
MAX705/MAX707/MAX813L generate a reset pulse when
the supply voltage drops below 4.65V, while the
MAX706/MAX708 generate a reset pulse below 4.40V.
All four parts are available in 8-pin DIP, SO and µMAX
packages.
_______________________Applications
___________________________Features
♦ µMAX Package: Smallest 8-Pin SO
♦ Guaranteed RESET Valid at VCC = 1V
♦ Precision Supply-Voltage Monitor
4.65V in MAX705/MAX707/MAX813L
4.40V in MAX706/MAX708
♦ 200ms Reset Pulse Width
♦ Debounced TTL/CMOS-Compatible
Manual-Reset Input
♦ Independent Watchdog Timer—1.6sec Timeout
(MAX705/MAX706)
♦ Active-High Reset Output
(MAX707/MAX708/MAX813L)
♦ Voltage Monitor for Power-Fail or Low-Battery
Warning
______________Ordering Information
PART
TEMP. RANGE
MAX705CPA
0°C to +70°C
PIN-PACKAGE
8 Plastic DIP
MAX705CSA
0°C to +70°C
8 SO
MAX705CUA
0°C to +70°C
8 µMAX
MAX705C/D
0°C to +70°C
Dice*
Ordering Information continued at end of data sheet.
* Dice are specified at TA = +25°C.
**Contact factory for availability and processing to MIL-STD-883.
_________________Pin Configurations
Computers
Controllers
Intelligent Instruments
Automotive Systems
Critical µP Power Monitoring
TOP VIEW
MR
1
VCC
2
GND 3
__________Typical Operating Circuit
PFI 4
MAX705
MAX706
MAX813L
8
WDO
7
RESET (RESET)
6
WDI
5
PFO
8
RESET
7
RESET
6
N.C.
5
PFO
DIP/SO
UNREGULATED DC
MAX667
+5V DC LINEAR
REGULATOR
µP
VCC
PFI
PUSHBUTTON
SWITCH
MR
RESET
PFI
MAX705 WDO
MAX706 PFO
MAX813L
VCC
RESET
I/O LINE
NMI
INTERRUPT
MR
1
VCC
2
GND 3
MAX707
MAX708
PFI 4
DIP/SO
( ) ARE FOR MAX813L ONLY.
Pin Configurations continued at end of data sheet.
________________________________________________________________ Maxim Integrated Products
Call toll free 1-800-998-8800 for free samples or literature.
1
MAX705–MAX708/MAX813L
_______________General Description
MAX705–MAX708/MAX813L
Low-Cost, µP Supervisory Circuits
ABSOLUTE MAXIMUM RATINGS
Terminal Voltage (with respect to GND)
VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to 6.0V
All Other Inputs (Note 1) . . . . . . . . . . . . . . . -0.3V to (VCC + 0.3V)
Input Current
VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20mA
GND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20mA
Output Current (all outputs) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20mA
Continuous Power Dissipation
Plastic DIP (derate 9.09mW/°C above +70°C) . . . . . . . 727mW
SO (derate 5.88mW/°C above +70°C) . . . . . . . . . . . . . . . 471mW
µMAX (derate 4.10mW/°C above +70°C) . . . . . . . . . . . . 330mW
CERDIP (derate 8.00mW/°C above +70°C) . . . . . . . . . . 640mW
Operating Temperature Ranges
MAX70_C__, MAX813LC__ . . . . . . . . . . . . . . . . . . . . 0°C to +70°C
MAX70_E__, MAX813LE__ . . . . . . . . . . . . . . . . . . . -40°C to +85°C
MAX70_MJA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -55°C to +125°C
Storage Temperature Range . . . . . . . . . . . . . . . . -65°C to +160°C
Lead Temperature (soldering, 10sec) . . . . . . . . . . . . . . . . +300°C
Note 1: The input voltage limits on PFI and MR can be exceeded if the input current is less than 10mA.
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 = 4.75V to 5.5V for MAX705/MAX707/MAX813L, VCC = 4.5V to 5.5V for MAX706/MAX708, TA = TMIN to TMAX, unless otherwise noted.)
PARAMETER
Operating Voltage Range
Supply Current
SYMBOL
VCC
ISUPPLY
Reset Threshold (Note 2)
VRT
Reset Threshold Hysteresis (Note 2)
Reset Pulse Width (Note 2)
tRS
RESET Output Voltage
RESET Output Voltage
Watchdog Timeout Period
WDI Pulse Width
Low
WDI Input Threshold
High
WDI Input Current
WDO Output Voltage
2
tWD
tWP
CONDITIONS
MIN
MAX70_C
MAX813LC
MAX70_E/M, MAX813LE/M
MAX705C, MAX706C, MAX813LC
MAX705E/M, MAX706E/M, MAX813LE/M
MAX707C, MAX708C
MAX707E/M, MAX708E/M
MAX705, MAX707, MAX813L
MAX706, MAX708
1.0
1.1
1.2
4.50
4.25
140
VCC - 1.5
TYP
150
150
50
50
4.65
4.40
40
200
ISOURCE = 800µA
ISINK = 3.2mA
MAX70_C, VCC = 1V, ISINK = 50µA
MAX70_E/M, VCC = 1.2V, ISINK = 100µA
MAX707, MAX708, ISOURCE = 800µA
VCC - 1.5
MAX707, MAX708, ISINK = 1.2mA
MAX813LC, ISOURCE = 4µA, VCC = 1.1V
0.8
MAX813LE/M, ISOURCE = 4µA, VCC = 1.2V
0.9
ISOURCE = 800µA
VCC - 1.5
MAX813L
ISINK = 3.2mA
MAX705, MAX706, MAX813L
1.00
1.60
VIL = 0.4V, VIH = (VCC) (0.8)
50
MAX705, MAX706, MAX813L,
VCC = 5V
MAX705, MAX706, MAX813L, WDI = VCC
MAX705, MAX706, MAX813L, WDI = 0V
MAX705, MAX706, MAX813L,
ISOURCE = 800µA
MAX
5.5
5.5
5.5
350
500
350
500
4.75
4.50
280
0.4
0.3
0.3
µA
V
mV
ms
V
V
0.4
2.25
0.8
50
-50
V
0.4
3.5
-150
UNITS
150
sec
ns
V
µA
VCC - 1.5
MAX705, MAX706, MAX813L,
ISINK = 1.2mA
_______________________________________________________________________________________
V
0.4
Low-Cost, µP Supervisory Circuits
(VCC = 4.75V to 5.5V for MAX705/MAX707/MAX813L, VCC = 4.5V to 5.5V for MAX706/MAX708, TA = TMIN to TMAX, unless otherwise noted.)
PARAMETER
SYMBOL
MR Pull-Up Current
CONDITIONS
MR = 0V
MR Pulse Width
tMR
MR to Reset Out Delay (Note 2)
PFI Input Threshold
MAX
UNITS
250
600
µA
ns
0.8
2.0
tMD
250
VCC = 5V
PFI Input Current
PFO Output Voltage
TYP
100
150
Low
High
MR Input Threshold
MIN
ISOURCE = 800µA
ISINK = 3.2mA
V
ns
1.20
1.25
1.30
V
-25.00
0.01
25.00
nA
VCC - 1.5
0.4
V
Note 2: Applies to both RESET in the MAX705-MAX708 and RESET in the MAX707/MAX708/MAX813L.
_______________________________________________________________________________________
3
MAX705–MAX708/MAX813L
ELECTRICAL CHARACTERISTICS (continued)
__________________________________________Typical Operating Characteristics
MAX705/MAX707
RESET OUTPUT VOLTAGE
vs. SUPPLY VOLTAGE
MAX705/MAX707
RESET RESPONSE TIME
POWER-FAIL COMPARATOR
DE-ASSERTION RESPONSE TIME
+5V
VCC
+4V
TA = +25°C
VCC
GND
RESET
330pF
1V/div
RESET
RESET
VCC
2k
PFO
30pF
1k
+1.25V
+3V
1V/div
+5V
VCC
VCC = +5V
TA = +25°C
PFO
+5V
0V
+5V
PFI
+5V
VCC
TA = +25°C
1V/div
RESET
VCC
RESET
GND
10k
0V
RESET
30pF
PFI
+1.30V
+1.20V
0V
0V
500ms/div
2µs/div
400ns/div
POWER-FAIL COMPARATOR
ASSERTION RESPONSE TIME
MAX707
RESET, RESET ASSERTION
MAX707
RESET, RESET DE-ASSERTION
VCC = VRT
TA = +25°C
+5V
+5V
PFO
PFI
PFO
1k
+5V
RESET
RESET
GND
0V
50mV/div
VCC = +5V
TA = +25°C
10k
+5V
10k
330pF
330pF
10k
330pF
RESET
400ns/div
MAX707/MAX708/MAX813L
RESET OUTPUT VOLTAGE
vs. SUPPLY VOLTAGE
400ns/div
MAX813L
RESET RESPONSE TIME
+5V
+5V
TA = +25°C
1V/div
0V
+5V
10k
+4V
VCC
RESET
0V
GND
10k
330pF
+4V
330pF
0V
0V
500ms/div
4
VCC
1V/div
RESET
VCC
RESET
GND
330pF
0V
400ns/div
VCC
RESET
10k
RESET
RESET
GND
RESET
0V
+1.20V
VCC
0V
2V/div
VCC
1V/div
0V
30pF
PFI
+5V
RESET
+1.25V
+1.30V
VCC = VRT
TA = +25°C
+5V
1V/div
MAX705–MAX708/MAX813L
Low-Cost, µP Supervisory Circuits
2µs/div
_______________________________________________________________________________________
Low-Cost, µP Supervisory Circuits
PIN
MAX705/MAX706
MAX707/MAX708
DIP/SO
DIP/SO
µMAX
µMAX
MAX813L
DIP/SO
NAME
FUNCTION
µMAX
1
3
1
3
1
3
MR
Manual-Reset Input triggers a reset pulse when
pulled below 0.8V. This active-low input has an internal 250µA pull-up current. It can be driven from a TTL
or CMOS logic line as well as shorted to ground with
a switch.
2
4
2
4
2
4
VCC
+5V Supply Input
3
5
3
5
3
5
GND
0V Ground Reference for all signals
4
6
4
6
4
6
PFI
Power-Fail Voltage Monitor Input. When PFI is less
than 1.25V, PFO goes low. Connect PFI to GND or
VCC when not used.
5
7
5
7
5
7
PFO
Power-Fail Output goes low and sinks current when
PFI is less than 1.25V; otherwise PFO stays high.
6
8
-
-
6
8
WDI
Watchdog Input. If WDI remains high or low for
1.6sec, the internal watchdog timer runs out and
WDO goes low (Figure 1). Floating WDI or connecting WDI to a high-impedance three-state buffer disables the watchdog feature. The internal watchdog
timer clears whenever reset is asserted, WDI is threestated, or WDI sees a rising or falling edge.
-
-
6
-
-
-
N.C.
No Connect
7
8
-
1
2
-
7
-
8
1
-
2
-
8
7
-
2
1
RESET
Active-Low Reset Output pulses low for 200ms when
triggered, and stays low whenever VCC is below the
reset threshold (4.65V in the MAX705 and 4.40V in the
MAX706). It remains low for 200ms after VCC rises
above the reset threshold or MR goes from low to high
(Figure 3). A watchdog timeout will not trigger RESET
unless WDO is connected to MR.
WDO
Watchdog Output pulls low when the internal watchdog timer finishes its 1.6sec count and does not go
high again until the watchdog is cleared. WDO also
goes low during low-line conditions. Whenever VCC is
below the reset threshold, WDO stays low; however,
unlike RESET, WDO does not have a minimum pulse
width. As soon as VCC rises above the reset threshold, WDO goes high with no delay.
RESET
Active-High Reset Output is the inverse of RESET.
Whenever RESET is high, RESET is low, and vice
versa (Figure 2). The MAX813L has a RESET output
only.
_______________________________________________________________________________________
5
MAX705–MAX708/MAX813L
______________________________________________________________Pin Description
MAX705–MAX708/MAX813L
Low-Cost, µP Supervisory Circuits
WDI
6
WATCHDOG
TRANSITION
DETECTOR
WATCHDOG
TIMER
VCC
VCC
WDO
1
MR
7
RESET
GENERATOR
2
8
VCC
RESET
(RESET)
VCC
1
RESET
GENERATOR
2
4.65V*
PFI
PFI
5
7
RESET
MAX707
MAX708
4.65V*
MAX705
MAX706
MAX813L
4
RESET
250µA
TIMEBASE FOR
RESET AND
WATCHDOG
250µA
MR
8
4
5
PFO
PFO
1.25V
1.25V
* 4.40V FOR MAX7O6.
( ) ARE FOR MAX813L ONLY.
3
3
GND
GND
* 4.40V FOR MAX7O6.
Figure 1. MAX705/MAX706/MAX813L Block Diagram
Figure 2. MAX707/MAX708 Block Diagram
_______________Detailed Description
WDI input is three-stated, the watchdog timer will stay
cleared and will not count. As soon as reset is released
and WDI is driven high or low, the timer will start counting.
Pulses as short as 50ns can be detected.
Typically, WDO will be connected to the non-maskable
interrupt input (NMI) of a µP. When VCC drops below
the reset threshold, WDO will go low whether or not the
watchdog timer has timed out yet. Normally this would
trigger an NMI interrupt, but RESET goes low simultaneously, and thus overrides the NMI interrupt.
If WDI is left unconnected, WDO can be used as a lowline output. Since floating WDI disables the internal
timer, WDO goes low only when VCC falls below the
reset threshold, thus functioning as a low-line output.
The MAX705/MAX706 have a watchdog timer and a
RESET output. The MAX707/MAX708 have both activehigh and active-low reset outputs. The MAX813L has
both an active-high reset output and a watchdog timer.
Reset Output
A microprocessor’s (µP’s) reset input starts the µP in a
known state. Whenever the µP is in an unknown state, it
should be held in reset. The MAX705-MAX708/MAX813L
assert reset during power-up and prevent code execution errors during power-down or brownout conditions.
On power-up, once VCC reaches 1V, RESET is a guaranteed logic low of 0.4V or less. As VCC rises, RESET stays
low. When VCC rises above the reset threshold, an internal timer releases RESET after about 200ms. RESET pulses low whenever VCC dips below the reset threshold, i.e.
brownout condition. If brownout occurs in the middle of
a previously initiated reset pulse, the pulse continues for
at least another 140ms. On power-down, once VCC falls
below the reset threshold, RESET stays low and is guaranteed to be 0.4V or less until VCC drops below 1V.
The MAX707/MAX708/MAX813L active-high RESET output
is simply the complement of the RESET output, and is
guaranteed to be valid with VCC down to 1.1V. Some µPs,
such as Intel’s 80C51, require an active-high reset pulse.
Watchdog Timer
The MAX705/MAX706/MAX813L watchdog circuit monitors the µP’s activity. If the µP does not toggle the watchdog input (WDI) within 1.6sec and WDI is not three-stated, WDO goes low. As long as RESET is asserted or the
6
Manual Reset
The manual-reset input (MR) allows reset to be triggered by a pushbutton switch. The switch is effectively
debounced by the 140ms minimum reset pulse width.
MR is TTL/CMOS logic compatible, so it can be driven
by an external logic line. MR can be used to force a
watchdog timeout to generate a reset pulse in the
MAX705/MAX706/MAX813L. Simply connect WDO to
MR.
_______________________________________________________________________________________
Low-Cost, µP Supervisory Circuits
tWP
WDI
tWD
tWD
tWD
0V
When VCC falls below 1V, the MAX705-MAX708 RESET
output no longer sinks current—it becomes an open circuit. High-impedance CMOS logic inputs can drift to
undetermined voltages if left undriven. If a pull-down
resistor is added to the RESET pin as shown in Figure 5,
any stray charge or leakage currents will be drained to
ground, holding RESET low. Resistor value (R1) is not
critical. It should be about 100kΩ, large enough not to
load RESET and small enough to pull RESET to ground.
+5V
0V
+5V
RESET
0V
RESET EXTERNALLY
TRIGGERED BY MR
+5V
(RESET)
tRS
Monitoring Voltages Other Than the
Unregulated DC Input
0V
( ) ARE FOR MAX813L ONLY.
Figure 3. MAX705/MAX706/MAX813L Watchdog TIming
VRT
VRT
VCC
tRS
tRS
+5V
RESET
+5V
MR
0V
tMD
tMR
WDO
0V
Monitor voltages other than the unregulated DC by
connecting a voltage divider to PFI and adjusting the
ratio appropriately. If required, add hysteresis by connecting a resistor (with a value approximately 10 times
the sum of the two resistors in the potential divider network) between PFI and PFO. A capacitor between PFI
and GND will reduce the power-fail circuit’s sensitivity
to high-frequency noise on the line being monitored.
RESET can be asserted on other voltages in addition to
the +5V VCC line. Connect PFO to MR to initiate a RESET
pulse when PFI drops below 1.25V. Figure 6 shows the
MAX705-MAX708 configured to assert RESET when the
+5V supply falls below the reset threshold, or when the
+12V supply falls below approximately 11V.
Monitoring a Negative Voltage
0V
+5V
__________Applications Information
Ensuring a Valid RESET
Output Down to VCC = 0V
+5V
WDO
To build an early-warning circuit for power failure, connect the PFI pin to a voltage divider (see Typical
Operating Circuit). Choose the voltage divider ratio so
that the voltage at PFI falls below 1.25V just before the
+5V regulator drops out. Use PFO to interrupt the µP
so it can prepare for an orderly power-down.
MR EXTERNALLY DRIVEN LOW
The power-fail comparator can also monitor a negative
supply rail (Figure 7). When the negative rail is good (a
negative voltage of large magnitude), PFO is low, and
when the negative rail is degraded (a negative voltage
of lesser magnitude), PFO is high. By adding the resistors and transistor as shown, a high PFO triggers reset.
As long as PFO remains high, the MAX705MAX708/MAX813L will keep reset asserted (RESET =
low, RESET = high). Note that this circuit’s accuracy
depends on the PFI threshold tolerance, the VCC line,
and the resistors.
Figure 4. MAX705/MAX706 RESET, MR, and WDO Timing with
WDI Three-Stated. The MAX707/MAX708/MAX813L RESET
output is the inverse of RESET shown.
_______________________________________________________________________________________
7
MAX705–MAX708/MAX813L
Power-Fail Comparator
The power-fail comparator can be used for various purposes because its output and noninverting input are
not internally connected. The inverting input is internally connected to a 1.25V reference.
MAX705–MAX708/MAX813L
Low-Cost, µP Supervisory Circuits
+12V
+5V
VCC
1M
1%
TO µP
RESET
MAX70_
MAX70_
MR
130k
1%
RESET
PFI
PFO
GND
R1
PARAMETER
MIN
TYP
MAX
UNIT
+12V Reset
10.67 10.87 11.50
Threshold at +25°C
Figure 5. RESET Valid to Ground Circuit
V
Figure 6. Monitoring Both +5V and +12V
+5V
BUFFERED RESET TO OTHER SYSTEM COMPONENTS
VCC
100k
MR
R1
MAX70_
100k
2N3904
PFO
PFI
VCC
VCC
MAX70_
R2
RESET
TO µP
GND
V-
µP
4.7k
RESET
GND
+5V
MR
RESET
GND
0V
+5V
PFO
0V
VTRIP
V5 − 1.25
R1
=
1.25 − VTRIP
R2
, VTRIP < 0
Figure 7. Monitoring a Negative Voltage
8
Figure 8. Interfacing to µPs with Bidirectional Reset I/O
0V
Interfacing to µPs with
Bidirectional Reset Pins
µPs with bidirectional reset pins, such as the Motorola
68HC11 series, can contend with the MAX705-MAX708
RESET output. If, for example, the RESET output is driven
high and the µP wants to pull it low, indeterminate logic
levels may result. To correct this, connect a 4.7kΩ
resistor between the RESET output and the µP reset I/O,
as in Figure 8. Buffer the RESET output to other system
components.
_______________________________________________________________________________________
Low-Cost, µP Supervisory Circuits
PART
TEMP. RANGE
PIN-PACKAGE
MAX705EPA
-40°C to +85°C
8 Plastic DIP
MAX705ESA
-40°C to +85°C
8 SO
_______Pin Configuration (continued)
TOP VIEW
(RESET) RESET
1
MAX705MJA
-55°C to +125°C
8 CERDIP**
WDO
2
MAX706CPA
0°C to +70°C
8 Plastic DIP
MR
3
MAX706CSA
0°C to +70°C
8 SO
V CC
4
MAX706CUA
0°C to +70°C
8 µMAX
MAX706C/D
0°C to +70°C
Dice*
MAX706EPA
-40°C to +85°C
8 Plastic DIP
MAX706ESA
-40°C to +85°C
8 SO
MAX706MJA
-55°C to +125°C
8 CERDIP**
MAX707CPA
0°C to +70°C
8 Plastic DIP
MAX707CSA
0°C to +70°C
8 SO
MAX707CUA
0°C to +70°C
8 µMAX
MAX707C/D
0°C to +70°C
Dice*
MAX707EPA
-40°C to +85°C
8 Plastic DIP
MAX707ESA
-40°C to +85°C
8 SO
MAX707MJA
-55°C to +125°C
8 CERDIP**
MAX708CPA
0°C to +70°C
8 Plastic DIP
MAX708CSA
0°C to +70°C
8 SO
MAX708CUA
0°C to +70°C
8 µMAX
MAX708C/D
0°C to +70°C
Dice*
MAX708EPA
-40°C to +85°C
MAX705
MAX706
MAX813L
8
WDI
7
PFO
6
PFI
5
GND
8
N.C.
7
PFO
6
PFI
5
GND
µMAX
RESET
1
RESET
2
MR
3
V CC
4
MAX707
MAX708
µMAX
( ) ARE FOR MAX813L ONLY.
____________________Chip Topography
V CC MR WDO/RESET
8 Plastic DIP
MAX708ESA
-40°C to +85°C
8 SO
MAX708MJA
-55°C to +125°C
8 CERDIP**
MAX813LCPA
0°C to +70°C
8 Plastic DIP
MAX813LCSA
0°C to +70°C
8 SO
MAX813LCUA
0°C to +70°C
8 µMAX
MAX813LC/D
0°C to +70°C
Dice*
MAX813LEPA
-40°C to +85°C
8 Plastic DIP
MAX813LESA
-40°C to +85°C
8 SO
MAX813LMJA
-55°C to +125°C
8 CERDIP**
* Dice are specified at TA = +25 °C.
**Contact factory for availability and processing to MIL-STD-883.
RESET (RESET)
WDI/N.C.
0.051"
(1.30mm)
GND
PFI
PFO
0.074"
(1.88mm)
( ) ARE FOR MAX813L ONLY.
TRANSISTOR COUNT: 572
SUBSTRATE MUST BE LEFT UNCONNECTED.
_______________________________________________________________________________________
9
MAX705–MAX708/MAX813L
__Ordering Information (continued)
MAX705–MAX708/MAX813L
Low-Cost, µP Supervisory Circuits
_______________________________________________________Package Information
DIM
C
α
A
0.101mm
0.004 in
e
B
A1
L
A
A1
B
C
D
E
e
H
L
α
INCHES
MAX
MIN
0.044
0.036
0.008
0.004
0.014
0.010
0.007
0.005
0.120
0.116
0.120
0.116
0.0256
0.198
0.188
0.026
0.016
6°
0°
MILLIMETERS
MIN
MAX
0.91
1.11
0.10
0.20
0.25
0.36
0.13
0.18
2.95
3.05
2.95
3.05
0.65
4.78
5.03
0.41
0.66
0°
6°
21-0036D
E
H
8-PIN µMAX
MICROMAX SMALL-OUTLINE
PACKAGE
D
10
______________________________________________________________________________________
______________________________________________________________________________________
†
††
6
10
6
TBD
TBD
✔
✔
✔
✔
✔
2.5
TBD
TBD
TBD
1.2
TBD
10
✔
✔
✔
✔
✔
✔
✔
1.2
✔
667
400
TBD
TBD
400
400
TBD
TBD
TBD
25
TBD
400
25
400
400
✔
✔/10ns
✔
✔
✔
✔
✔
✔/10ns
✔/10ns
✔/10ns
✔
✔/10ns
VBATT-to-VOUT
On Resistance
Max (Ω)
–—–
CE Write
Protect
400
400
25
Power-Fail
Comparator
✔/±2%
✔/±2%
✔/±2%
✔/±2%
✔/±2%
✔/±2%
✔
✔/±2%
✔
✔/±2%
✔
✔/±2%
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
Manual-Reset
Input
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
✔
Low-Line
Output
Nominal
Watchdog
Timeout Period
(sec), if Available
–————–
RESET Valid
to VCC = 1V
Active-High
Reset
Active-Low
Reset
Minimum Reset
Pulse Width (ms)
Nominal Reset
Threshold (V)
Battery-On
Output
✔
✔
✔
✔
✔
Prices provided are for design guidance and are FOB USA (unless otherwise noted). International prices will differ due to local duties, taxes, and exchange rates.
Future product—contact factory for pricing and availability. Specifications are preliminary.
25,000 pc. price, factory direct
MXD1210
MAX813L
MAX814K/L/N/T
MAX815K/L/N/T
MAX816
MAX820L/M/R/S/T
MAX810L/M/R/S/T
MAX806R/S/T
MAX807L/N/M
MAX808L/N/M
MAX809L/M/R/S/T
MAX804R/S/T
MAX805L/M/R/S/T
MAX793R/S/U/T
MAX794
MAX795R/S/U/T
MAX800L/M
MAX801L/N/M
MAX802L/M/R/S/T
10
6
10
6
1.2
VCC-to-VOUT
On Resistance
Max (Ω)
✔
✔
✔
✔
✔
✔
Separate
Watchdog
Output
Backup-Battery
Switch
4.37/4.62
250
✔
✔
✔
0.15/0.6/1.2
4.65/4.40
140
✔
✔
1.6
2.63/2.93/3.08
140
✔
✔
1.6
4.65/4.40
140/adj. ✔
✔
✔
1.6/adj.
✔
The MAX1691 is a module with the MAX691A and a 125mAh lithium battery
Adj.
35/adj.
✔
✔
1.6/adj.
✔
Adj.
35/adj.
✔
✔
1.6/adj.
✔
4.65/adj.
200
✔
✔
4.65/4.40
140
✔
✔
2.63/2.93/3.08
140
✔
✔
4.65/4.40
140
✔
✔
1.6
✔
2.63
140
✔
✔
1.6
✔
2.63/2.93/3.08
140
✔
✔
1.6
✔
4.65/4.40
140
✔
✔
✔
2.63/2.93/3.08
140
✔
✔
✔
4.65
140
✔
✔
✔
1
✔
4.65/4.40/
140
✔
✔
✔
1
✔
2.63/2.93/3.08
2.63/2.93/3.07/3.08 140
✔
✔
✔
1.6
✔
Adj.
140
✔
✔
✔
1.6
✔
2.63/2.93/3.07/3.08 140
✔
✔
4.60/4.40
140
✔
✔
✔
1.6/adj.
✔
4.68/4.58/4.43
140
✔/±1.5%
✔
1.6
4.60/4.40/
140
✔
✔
1.6
2.63/2.93/3.08
2.63/2.93/3.08
140
✔
✔
1.6
4.65/4.40/
140
✔
✔
1.6
2.63/2.93/3.08
2.63/2.93/3.08
140
✔
✔
✔
4.68/4.58/4.43
140
✔/±1.5% ✔/±1.5% ✔
1.6
✔
4.68/4.58/4.43
140
✔/±1.5%
✔
4.65/4.40/
140
✔
✔
2.63/2.93/3.08
4.65/4.40/
140
✔
✔
2.63/2.93/3.08
4.65
140
✔
✔
1.6
✔
4.80/4.70/4.55/3.03 140
✔/±1% ✔/±1%
✔
4.80/4.70/4.55/3.03 140
✔/±1%
✔
1.6
✔
Adj./±1%
140
✔
✔
✔
4.65/4.40/
140
✔
✔
✔
1
✔
2.63/2.93/3.08
4.37/4.62
ISUPPLY
Operating Mode
mA
max (typ)
0.5(0.23)
0.35(0.2)
TBD
TBD
TBD
0.15(0.07)
0.06(0.024)
0.5(0.4)
TBD
TBD
0.06(0.024)
0.5(0.4)
0.35(0.2)
TBD
TBD
TBD
0.1(0.035)
TBD
0.35(0.2)
0.2(0.1)
0.35(0.2)
0.5(0.4)
0.35(0.2)
0.35(0.2)
0.35(0.2)
0.35(0.2)
0.35(0.2)
0.15(0.06)
0.15(0.07)
0.2(0.05)
0.35(0.2)
0.5(0.4)
0.1(0.035)
ISUPPLY
Backup Mode
µA
max (typ)
0.1(0.002)
TBD
TBD
TBD
1(0.4)
TBD
TBD
1(0.4)
5(0.05)
TBD
TBD
TBD
5(0.04)
TBD
5(0.05)
5(0.04)
5(0.05)
1(0.4)
5(0.05)
1(0.4)
5(0.04)
8
8
8
8
8
16
3
8
8
16
3
8
8
16
16
8
16
8
8
8
8
8
16
16
16
16
8
8
8
8
8
8
8
8
16
16
Pins
2.44
1.02*
††
††
††
3.82
††
3.90
††
††
††
3.66
3.26
††
††
††
3.88
††
3.59
1.71
3.26
3.23
3.61
††
3.55
3.58
2.17
1.38*
2.93
1.02*
1.71
1.71
0.88*
1.63
3.90
3.42
MAX705–MAX708/MAX813L
*
Part
Number
MAX1232
MAX690A/692A
MAX690R/S/T
MAX691A/693A
MAX1691
MAX696
MAX697
MAX700
MAX703/704
MAX704R/S/T
MAX705/706
MAX706P
MAX706R/S/T
MAX707/708
MAX708R/S/T
MAX791
MAX792L/M/R/S/T
Price†
1000-up ($)
___________________________________________µP Supervisory Circuits
Low-Cost, µP Supervisory Circuits
11
MAX705–MAX708/MAX813L
Low-Cost, µP Supervisory Circuits
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.
12 __________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 (408) 737-7600
© 1995 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.