_______________General Description
These microprocessor (P) supervisory circuits reduce
the complexity and number of components required for
power-supply monitoring and battery-control functions
in P systems. They significantly improve system relia-
bility and accuracy compared to separate ICs or
discrete components.
These devices are designed for use in systems powered
by 3.0V or 3.3V supplies. See the selector guide in the
back of this data sheet for similar devices designed for
5V systems. The suffixes denote different reset threshold
voltages: 3.075V (T), 2.925V (S), and 2.625V (R) (see
Reset Threshold section in the Detailed Description). All
these parts are available in 8-pin DIP and SO packages.
Functions offered in this series are as follows:
________________________Applications
Battery-Powered Computers and Controllers
Embedded Controllers
Intelligent Instruments
Automotive Systems
Critical P Power Monitoring
Portable Equipment
____________________________Features
o
R
--
E
--
S
--
E
--
T
and RESET Outputs
o
Manual Reset Input
o
Precision Supply-Voltage Monitor
o
200ms Reset Time Delay
o
Watchdog Timer (1.6sec timeout)
o
Battery-Backup Power Switching--
Battery Can Exceed V
CC
in Normal Operation
o
40A V
CC
Supply Current
o
1A Battery Supply Current
o
Voltage Monitor for Power-Fail or
Low-Battery Warning
o
Guaranteed
R
--
E
--
S
--
E
--
T
Assertion to V
CC
= 1V
o
8-Pin DIP and SO Packages
______________Ordering Information
Ordering Information continued on last page.
* Contact factory for dice specifications.
** These parts offer a choice of reset threshold voltage. Select
the letter corresponding to the desired nominal reset threshold
voltage (T = 3.075V, S = 2.925V, R = 2.625V) and insert it into
the blank to complete the part number.
MAX690T/S/R, 704T/S/R, 802T/S/R, 804806T/S/R
3.0V/3.3V Microprocessor Supervisory Circuits
________________________________________________________________
Maxim Integrated Products
1
MAX690T/S/R
MAX802T/S/R
MAX804T/S/R
MAX805T/S/R
0.1
F
V
OUT
RESET
(RESET)
PFO
WDI
R1
VBATT
V
CC
GND
GND
GND
V
CC
0.1
F
0.1
F
3.6V
LITHIUM
BATTERY
CMOS RAM
P
V
CC
RESET
NMI
I/O LINE
UNREGULATED
DC
REGULATED +3.3V OR +3.0V
R2
BUS
( ) ARE FOR MAX804T/S/R, MAX805T/S/R
PFI
See last page for MAX704T/S/R, MAX806T/S/R.
__________________Pin Configuration
1
2
3
4
8
7
6
5
DIP/SO
TOP VIEW
PFO
VBATT
RESET (RESET)
WDI
<
MR
>
V
OUT
V
CC
GND
PFI
MAX690T/S/R
MAX704T/S/R
MAX802T/S/R
MAX804T/S/R
MAX805T/S/R
MAX806T/S/R
( ) ARE FOR MAX804T/S/R, MAX805T/S/R
< >
ARE FOR MAX704T/S/R, MAX806T/S/R
_________Typical Operating Circuits
Call toll free 1-800-998-8800 for free samples or literature.
19-0243; Rev 1; 9/94
PART**
TEMP. RANGE
MAX690
_CPA
0C to +70C
MAX690_CSA
0C to +70C
MAX690_C/D
0C to +70C
Dice*
8 SO
8 Plastic DIP
PIN-PACKAGE
Part
MAX690_EPA
-40C to +85C
MAX690_ESA
-40C to +85C
MAX690_MJA
-55C to +125C
8 CERDIP
8 SO
8 Plastic DIP
Active-Low Reset
Active-High Reset
Watchdog Input
Manual Reset
Input
Backup-Battery
Switch
Power-Fail
Threshold Accuracy
Power-Fail
Comparator
Reset Window
MAX690
4%
75mV
MAX704
4%
75mV
MAX802
2%
2%
MAX804
2%
2%
MAX805
4%
75mV
MAX806
2%
2%
MAX690T/S/R, 704T/S/R, 802T/S/R, 804806T/S/R
3.0V/3.3V Microprocessor Supervisory Circuits
2
_______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(V
CC
= 3.17V to 5.5V for the MAX690T/MAX704T/MAX80_T, V
CC
= 3.02V to 5.5V for the MAX690S/MAX704S/MAX80_S, V
CC
= 2.72V to
5.5V for the MAX690R/MAX704R/MAX80_R; VBATT = 3.6V; T
A
= T
MIN
to T
MAX
; unless otherwise noted. Typical values are at T
A
= +25C.)
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.
Terminal Voltage (with respect to GND)
V
CC
.........................................................................-0.3V to 6.0V
VBATT ....................................................................-0.3V to 6.0V
All Other Inputs ...................-0.3V to the higher of V
CC
or VBATT
Continuous Input Current
V
CC
..................................................................................100mA
VBATT ...............................................................................18mA
GND ..................................................................................18mA
Output Current
R
--
E
--
S
--
E
--
T
,
P
--
F
--
O
....................................................................18mA
V
OUT
................................................................................100mA
Continuous Power Dissipation (T
A
= +70C)
Plastic DIP (derate 9.09mW/C above +70C) ..............727mW
SO (derate 5.88mW/C above +70C) ...........................471mW
CERDIP (derate 8.00mW/C above +70C) ...................640mW
Operating Temperature Ranges
MAX690_C_ _/MAX704_C_ _/MAX80_ _C_ _ ........0C to +70C
MAX690_E_ _/MAX704_E_ _/MAX80_ _E_ _. .....-40C to +85C
MAX690_M_ _/MAX704_M_ _/MAX80_ _M_ _...-55C to +125C
Storage Temperature Range .............................-65C to +160C
Lead Temperature (soldering, 10sec) .............................+300C
MAX690_M, MAX704_M,
MAX80_ _M, V
CC
< 5.5V
V
CC
= 2.0V, VBATT = 2.3V
V
CC
-
V
CC
-
0.0015
0.0006
V
OUT
Output Voltage
V
V
CC
-
V
CC
-
0.35
0.15
V
CC
-
V
CC
-
0.035
0.015
V
CC
-
V
CC
-
0.3
0.15
V
CC
-
V
CC
-
0.03
0.015
40
50
V
1.1
5.5
1.0
5.5
Operating Voltage Range,
V
CC
, VBATT (Note 1)
A
0.01
5
Battery Leakage Current
(Note 3)
0.01
0.5
A
0.4
10
VBATT Supply Current, Any Mode
(excluding I
OUT
) (Note 2)
0.4
1
50
65
40
55
A
50
70
I
SUPPLY
V
CC
Supply Current
(excluding I
OUT
)
A
25
50
V
CC
Supply Current in Battery-
Backup Mode (excluding I
OUT
)
UNITS
MIN
TYP
MAX
SYMBOL
PARAMETER
MAX690_C/E, MAX704_C/E, MAX80_ _C/E,
I
OUT
= 5mA (Note 4)
MAX690_E/M, MAX704_E/M, MAX80_ _E/M
MAX690_M, MAX704_M, MAX80_ _M
MAX690_M, MAX704_M, MAX80_ _M
M
--
R
= V
CC
(MAX704_/
MAX806_)
M
--
R
= V
CC
(MAX704_/
MAX806_)
CONDITIONS
MAX690_C, MAX704_C, MAX80_ _C
MAX690_C/E, MAX704_C/E, MAX80_ _C/E
MAX690_C/E, MAX704_C/E, MAX80_ _C/E
I
OUT
= 250A, V
CC
> 2.5V (Note 4)
MAX690_M, MAX704_M, MAX80_ _M
I
OUT
= 50mA
MAX690_M, MAX704_M, MAX80_ _M
I
OUT
= 5mA (Note 4)
MAX690_C/E, MAX704_C/E, MAX80_ _C/E
I
OUT
= 50mA
MAX690_C/E, MAX704_C/E,
MAX80_ _C/E, V
CC
< 3.6V
MAX690_C/E, MAX704_C/E,
MAX80_ _C/E, V
CC
< 5.5V
MAX690_M, MAX704_M,
MAX80_ _M, V
CC
< 3.6V
V
MAX690T/S/R, 704T/S/R, 802T/S/R, 804806T/S/R
3.0V/3.3V Microprocessor Supervisory Circuits
_______________________________________________________________________________________
3
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= 3.17V to 5.5V for the MAX690T/MAX704T/MAX80_T, V
CC
= 3.02V to 5.5V for the MAX690S/MAX704S/MAX80_S, V
CC
= 2.72V to
5.5V for the MAX690R/MAX704R/MAX80_R; VBATT = 3.6V; T
A
= T
MIN
to T
MAX
; unless otherwise noted. Typical values are at T
A
= +25C.)
A
-10
10
RESET Output Leakage Current
(Note 9)
-1
1
0.17
0.3
V
OL
P
--
F
--
O
,
R
--
E
--
S
--
E
--
T
Output Voltage
0.13
0.3
V
0.06
0.3
V
OL
P
--
F
--
O
,
R
--
E
--
S
--
E
--
T
, RESET
Output Voltage
mV
65
25
V
VBATT
- 0.14
VBATT
VBATT
- 0.1
- 0.034
V
OUT
in Battery-Backup Mode
V
180
500
I
OS
P
--
F
--
O
,
R
--
E
--
S
--
E
--
T
Output Short to
GND Current (Note 4)
V
V
CC
V
CC
- 0.3
- 0.05
V
OH
P
--
F
--
O
,
R
--
E
--
S
--
E
--
T
Output Voltage
ms
140
200
280
t
WP
Reset Timeout Period
3.00
3.085
3.14
V
2.30
2.40
2.50
V
SW
Battery Switch Threshold,
V
CC
Falling
3.00
3.075
3.15
3.00
3.085
3.17
3.00
3.075
3.12
UNITS
MIN
TYP
MAX
SYMBOL
PARAMETER
V
2.59
2.635
2.72
V
RST
Reset Threshold (Note 8)
2.55
2.625
2.70
2.55
2.635
2.72
2.59
2.625
2.70
2.88
2.935
3.02
2.85
2.925
3.00
2.85
2.935
3.02
2.88
2.925
3.00
V
Battery Switch Threshold,
V
CC
Rising (Note 7)
V
CC
rising
V
CC
falling
V
CC
rising
V
CC
falling
V
CC
rising
V
CC
falling
V
CC
rising
V
CC
falling
V
CC
rising
V
CC
falling
V
CC
rising
V
CC
falling
VBATT = 0V, V
CC
= 1.2V, I
SINK
= 200A,
MAX690_E/M, MAX704_E/M, MAX80_ _E/M
I
SINK
= 1.2mA;
MAX690_/704_/802_/806_, V
CC
= V
RST
min;
MAX804_/805_, V
CC
= V
RST
max
VBATT - V
CC
, V
SW
> V
CC
> 1.75V (Note 5)
I
OUT
= 250A, VBATT = 2.3V
V
CC
= 3.3V, V
OH
= 0V
I
SOURCE
= 50A
V
CC
< 3.6V
VBATT > V
CC
(Note 6)
MAX690S/704S/805S
CONDITIONS
This value is identical to the reset threshold,
V
CC
rising
VBATT = 0V,
V
CC
= V
RST
min;
V
RESET
= 0V, V
CC
VBATT = 0V, V
CC
= 1.0V, I
SINK
= 40A,
MAX690_C, MAX704_C, MAX80_ _C
MAX802R/804R/806S
MAX690T/704T/805T
MAX802T/804T/806T
MAX690R/704R/805R
MAX802S/804S/806S
I
OUT
= 1mA, VBATT = 2.3V
MAX804_E/M,
MAX805_E/M
MAX804_C,
MAX805_C
MAX690T/S/R, 704T/S/R, 802T/S/R, 804806T/S/R
3.0V/3.3V Microprocessor Supervisory Circuits
4
_______________________________________________________________________________________
nA
-500
2
500
PFI Input Current
-25
2
25
MIN
TYP
MAX
ns
100
20
t
MR
M
--
R
Pulse Width
V
0.3 x V
CC
V
IH
M
--
R
Input Threshold
0.7 x V
CC
ns
60
500
t
MD
M
--
R
to Reset Delay
A
20
60
350
M
--
R
Pull-Up Current
V
0.7 x V
CC
V
IH
0.3 x V
CC
V
IL
WDI Input Threshold
1.12
1.60
2.24
ns
100
20
WDI Pulse Width
V
IL
MAX690_M, MAX802_M,
MAX804_M, MAX805_M
-1
0.01
1
-10
0.01
10
A
WDI Input Current
MAX690/MAX802/MAX804/
MAX805 only
sec
t
WD
Watchdog Timeout Period
Note 1:
V
CC
supply current, logic input leakage, watchdog functionality (MAX690_/802_/805_/804_),
M
--
R
functionality
(MAX704_/806_), PFI functionality, state of
R
--
E
--
S
--
E
--
T
(MAX690_/704_/802_/806_), and RESET (MAX804_/805_) tested at
VBATT = 3.6V, and V
CC
= 5.5V. The state of
R
--
E
--
S
--
E
--
T
or RESET and
P
--
F
--
O
is tested at V
CC
= V
CC
min.
Note 2:
Tested at VBATT = 3.6V, V
CC
= 3.5V and 0V. The battery current will rise to 10A over a narrow transition window around
V
CC
= 1.9V.
Note 3:
Leakage current into the battery is tested under the worst-case conditions at V
CC
= 5.5V, VBATT = 1.8V and at V
CC
= 1.5V,
VBATT= 1.0V.
Note 4:
Guaranteed by design.
Note 5:
When V
SW
> V
CC
> VBATT, V
OUT
remains connected to V
CC
until V
CC
drops below VBATT. The V
CC
-to-VBATT comparator
has a small 25mV typical hysteresis to prevent oscillation. For V
CC
< 1.75V (typ), V
OUT
switches to VBATT regardless of the
voltage on VBATT.
Note 6:
When VBATT > V
CC
> V
SW
, V
OUT
remains connected to V
CC
until V
CC
drops below the battery switch threshold (V
SW
).
Note 7:
V
OUT
switches from VBATT to V
CC
when V
CC
rises above the reset threshold, independent of VBATT. Switchover back to
V
CC
occurs at the exact voltage that causes
R
--
E
--
S
--
E
--
T
to go high (on the MAX804_/805_, RESET goes low); however
switchover occurs 200ms prior to reset.
Note 8:
The reset threshold tolerance is wider for V
CC
rising than for V
CC
falling to accommodate the 10mV typical hysteresis, which
prevents internal oscillation.
Note 9:
The leakage current into or out of the RESET pin is tested with RESET asserted (RESET output high impedance).
MAX690_/MAX704_/MAX805_
V
1.187
1.237
1.287
V
PFT
PFI Input Threshold
1.212
1.237
1.262
SYMBOL
PARAMETER
UNITS
MAX704_/MAX806_ only
MAX704_/MAX806_ only
MAX704_/MAX806_ only,
M
--
R
= 0V, V
CC
= 3V
0V< V
CC
< 5.5V
MAX704_/MAX806_ only
MAX690_M, MAX704_M, MAX80_ _M
V
CC
< 3.6V
V
PFI
falling
CONDITIONS
MAX690_/MAX802_/MAX804_/MAX805_ only
V
CC
< 3.6V
MAX690_C/E, MAX704_C/E, MAX80_ _C/E
MAX802_C/E, MAX804_C/E,
MAX806_C/E
MAX690_C/E, MAX802_C/E,
MAX804_C/E, MAX805_C/E
MAX690_/MAX802_/MAX804_/MAX805_ only
MAX690_M, MAX704_M, MAX80_ _M
mV
10
25
nA
-500
2
500
PFI Input Current
-25
2
25
V
PFH
PFI Hysteresis, PFI Rising
10
20
MAX690_M, MAX704_M, MAX80_ _M
V
CC
< 3.6V
MAX690_C/E, MAX704_C/E, MAX80_ _C/E
MAX690_C/E, MAX704_C/E,
MAX80_ _C/E
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= 3.17V to 5.5V for the MAX690T/MAX704T/MAX80_T, V
CC
= 3.02V to 5.5V for the MAX690S/MAX704S/MAX80_S, V
CC
= 2.72V to
5.5V for the MAX690R/MAX704R/MAX80_R; VBATT = 3.6V; T
A
= T
MIN
to T
MAX
; unless otherwise noted. Typical values are at T
A
= +25C.)
MAX690T/S/R, 704T/S/R, 802T/S/R, 804806T/S/R
3.0V/3.3V Microprocessor Supervisory Circuits
_______________________________________________________________________________________
5
5
0
60
20
60
140
V
CC
-to-V
OUT
ON-RESISTANCE
vs. TEMPERATURE
1
4
MAX690-806 TOC01
TEMPERATURE (C)
V
CC
-to-V
OUT
ON-RESISTANCE (
)
20
100
40
0
80
40
120
3
2
V
CC
= 5V
V
CC
= 3.3V
V
CC
= 2.5V
VBATT = 3.0V
180
20
60
20
60
140
VBATT-to-V
OUT
ON-RESISTANCE
vs. TEMPERATURE
60
MAX690-806 TOC02
TEMPERATURE (C)
VBATT-to-V
OUT
ON-RESISTANCE (
)
20
100
40
0
80
40
120
140
100
V
CC
= 0V
VBATT = 3.3V
VBATT = 3V
VBATT = 2V
VBATT = 5V
50
25
60
20
60
140
SUPPLY CURRENT
vs. TEMPERATURE
30
45
MAX690-806 TOC03
TEMPERATURE (C)
SUPPLY CURRENT (
A)
20
100
40
0
80
40
120
40
35
V
CC
= 5V
V
CC
= 3.3V
V
CC
= 2.5V
VBATT = 3V
PFI = GND
MR/WDI FLOATING
10,000
0.1
60
20
60
140
BATTERY SUPPLY CURRENT
vs. TEMPERATURE
1
1000
MAX690-806 TOC04
TEMPERATURE (C)
BATTERY SUPPLY CURRENT (nA)
20
100
40
0
80
40
120
100
10
VBATT = 3V
VBATT = 5V
VBATT = 2V
V
CC
= 0V
PFI = GND
1.240
1.230
60
20
60
140
PFI THRESHOLD
vs. TEMPERATURE
1.232
1.238
MAX690-806 TOC07
TEMPERATURE (C)
PFI THRESHOLD (V)
20
100
40
0
80
40
120
1.236
1.234
V
CC
= 5V
V
CC
= 3.3V
V
CC
= 2.5V
VBATT = 3.0V
216
196
60
20
60
140
RESET TIMEOUT PERIOD
vs. TEMPERATURE
200
212
MAX690-806 TOC05
TEMPERATURE (C)
RESET TIMEOUT PERIOD (ms)
20
100
40
0
80
40
120
208
204
V
CC
= 5V
V
CC
= 3.3V
VBATT = 3.0V
30
10
60
20
60
140
RESET-COMPARATOR PROPAGATION
DELAY vs. TEMPERATURE
14
26
MAX690-806 TOC06
TEMPERATURE (C)
PROPAGATION DELAY (
s)
20
100
40
0
80
40
120
22
18
VBATT = 3.0V
100mV OVERDRIVE
1.004
0.994
60
20
60
140
NORMALIZED RESET THRESHOLD
vs. TEMPERATURE
0.996
1.002
MAX690-806 TOC08
TEMPERATURE (C)
NORMALIZED RESET THRESHOLD (V)
20
100
40
0
80
40
120
1.000
0.998
VBATT = 3.0V
__________________________________________Typical Operating Characteristics
(T
A
= +25C, unless otherwise noted.)
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