19-0094; Rev 10; 11/05
Microprocessor Supervisory Circuits
General Description
The MAX691A/MAX693A/MAX800L/MAX800M micro-
processor (µP) supervisory circuits are pin-compatible
upgrades to the MAX691, MAX693, and MAX695. They
improve performance with 30µA supply current, 200ms
typ reset active delay on power-up, and 6ns chip-
enable propagation delay. Features include write pro-
tection of CMOS RAM or EEPROM, separate watchdog
outputs, backup-battery switchover, and a
RESET
out-
put that is valid with V
CC
down to 1V. The MAX691A/
MAX800L have a 4.65V typical reset-threshold voltage,
and the MAX693A/MAX800Ms’ reset threshold is 4.4V
typical. The MAX800L/MAX800M guarantee power-fail
accuracies to ±2%.
____________________________Features
♦
200ms Power-OK/Reset Timeout Period
♦
1µA Standby Current, 30µA Operating Current
♦
On-Board Gating of Chip-Enable Signals,
10ns max Delay
♦
MaxCap
™
or SuperCap
™
Compatible
♦
Guaranteed
RESET
Assertion to V
CC
= +1V
♦
Voltage Monitor for Power-Fail or Low-Battery
Warning
♦
Power-Fail Accuracy Guaranteed to ±2%
(MAX800L/M)
♦
Available in 16-Pin Narrow SO, Plastic
DIP, and TSSOP Packages
MAX691A/MAX693A/MAX800L/MAX800M
________________________Applications
Computers
Controllers
Intelligent Instruments
Automotive Systems
Critical µP Power Monitoring
PART
MAX691ACUE
MAX691ACSE
MAX691ACWE
MAX691ACPE
MAX691AC/D
Ordering Information
TEMP RANGE
0°C to +70°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
PIN-PACKAGE
16 TSSOP
16 Narrow SO
16 Wide SO
16 Plastic DIP
Dice*
Typical Operating Circuit
+8V
5V
REGULATOR
0.1µF
3
V
CC
1
VBATT
CE OUT
0.47F*
5
BATT ON
1N4148
V
OUT
2
12
CMOS RAM
MAX691AEUE
0°C to +70°C
16 TSSOP
MAX691AESE
-40°C to +85°C
16 Narrow SO
MAX691AEWE
-40°C to +85°C
16 Wide SO
MAX691AEPE
-40°C to +85°C
16 Plastic DIP
MAX691AEJE
-40°C to +85°C
16 CERDIP
MAX691AMJE
-55°C to +125°C
16 CERDIP
Ordering Information continued on last page.
*Dice
are specified at T
A
= +25 °C, DC parameters only.
Devices in PDIP, SO and TSSOP packages are available in both
leaded and lead-free packaging. Specify lead free by adding
the + symbol at the end of the part number when ordering.
Lead free not available for CERDIP package.
MAX691A
9
MAX693A
CE IN 13
PFI
MAX800L
MAX800M
4
7
NO
CONNECTION
8
GND
WDI
OSC IN
PFO 10
OSC SEL
LOW LINE WDO
6
14
*MaxCap
RESET
15
11
Pin Configuration
TOP VIEW
VBATT 1
V
OUT
2
V
CC
3
GND 4
BATT ON 5
16 RESET
15 RESET
14 WDO
ADDRESS
DECODE
A0-A15
I/O
µP
NMI
RESET
AUDIBLE
ALARM
LOW LINE 6
OSC IN 7
OSC SEL 8
MAX691A
MAX693A
MAX800L
MAX800M
13 CE IN
12 CE OUT
11 WDI
10 PFO
9
PFI
SYSTEM STATUS INDICATORS
DIP/SO/TSSOP
SuperCap is a registered trademark of Baknor Industries. MaxCap is a registered trademark of The Carborundum Corp.
________________________________________________________________
Maxim Integrated Products
1
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.
Microprocessor Supervisory Circuits
MAX691A/MAX693A/MAX800L/MAX800M
ABSOLUTE MAXIMUM RATINGS
Terminal Voltage (with respect to GND)
V
CC
.......................................................................-0.3V to +6V
VBATT...................................................................-0.3V to +6V
All Other Inputs .....................................-0.3V to (V
OUT
+ 0.3V)
Input Current
V
CC
Peak...........................................................................1.0A
V
CC
Continuous.............................................................250mA
VBATT Peak ..................................................................250mA
VBATT Continuous ..........................................................25mA
GND, BATT ON .............................................................100mA
All Other Outputs ............................................................25mA
Continuous Power Dissipation (T
A
= +70°C)
TSSOP (derate 6.70mW/°C above +70°C) ..................533mW
Narrow SO (derate 8.70mW/°C above +70°C) ...........696mW
Wide SO (derate 9.52mW/°C above +70°C)...............762mW
Plastic DIP (derate 10.53mW/°C above +70°C) ..........842mW
CERDIP (derate 10.00mW/°C above +70°C) ..............800mW
Operating Temperature Ranges
MAX69_AC_ _/MAX800_C_ _ .............................0°C to +70°C
MAX69_AE_ _/MAX800_E_ _ ...........................-40°C to +85°C
MAX69_AMJE ................................................-55°C to +125°C
Storage Temperature Range .............................-65°C to +160°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
(MAX691A, MAX800L: V
CC
= +4.75V to +5.5V; MAX693A, MAX800M: V
CC
= +4.5V to +5.5V; VBATT = 2.8V, T
A
= T
MIN
to T
MAX
,
unless otherwise noted.)
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
Operating Voltage Range,
V
CC
, VBATT (Note 1)
I
OUT
= 25mA
MAX69_AC
V
OUT
Output
V
CC
= 4.5V
I
OUT
= 250mA
MAX69_AE,
MAX800_C/E
MAX69_A/M
I
OUT
= 210mA
MAX69_AC/AE,
MAX800_C/E
V
CC
- 0.17
0.8
0.8
0.8
VBATT - 0.3
VBATT - 0.25
VBATT - 0.15
15
25
30
30
0.04
100
1
µA
5
-0.1
-1.0
VBATT + 0.3
VBATT - 0.3
0.02
0.02
µA
V
0
V
CC
- 0.02
V
CC
- 0.2
V
CC
- 0.2
5.5
V
CC
- 0.05
V
CC
- 0.3
V
CC
- 0.35
V
CC
- 0.40
V
CC
- 0.3V
1.2
1.4
1.6
V
Ω
V
V
MAX69_AC, MAX800_C
V
CC
-to-V
OUT
On-Resistance V
CC
= 4.5V
MAX69_AE, MAX800_E
V
OUT
in Battery-Backup
Mode
VBATT-to-V
OUT
On-Resistance
Supply Current in
Normal Operating Mode
(excludes I
OUT
)
Supply Current in
Battery-Backup Mode
(excludes I
OUT
) (Note 2)
VBATT Standby Current
(Note 3)
Battery Switchover
Threshold
2
MAX69_A/M
VBATT = 4.5V, I
OUT
= 20mA
VBATT = 2.8V, I
OUT
= 10mA
VBATT = 2.0V, I
OUT
= 5mA
VBATT = 4.5V
VBATT = 2.8V
VBATT = 2.0V
V
CC
> VBATT - 1V
V
CC
< VBATT - 1.2V, T
A
= +25°C
VBATT = 2.8V
T
A
= T
MIN
+ T
MIN
VBATT + 0.2V
≤
V
CC
Power-up
Power-down
T
A
= +25°C
T
A
= T
MIN
+ T
MIN
Ω
µA
_______________________________________________________________________________________
Microprocessor Supervisory Circuits
ELECTRICAL CHARACTERISTICS (continued)
(MAX691A, MAX800L: V
CC
= +4.75V to +5.5V; MAX693A, MAX800M: V
CC
= +4.5V to +5.5V; VBATT = 2.8V, T
A
= T
MIN
to T
MAX
,
unless otherwise noted.)
PARAMETER
Battery Switchover
Hysteresis
BATT ON Output
Low Voltage
BATT ON Output
Short-Circuit Current
I
SINK
= 3.2mA
I
SINK
= 25mA
Sink current
Source current
CONDITIONS
MIN
TYP
60
0.1
0.7
60
15
4.65
4.40
0.4
1.5
100
4.75
4.50
4.70
4.45
15
Power-down
80
800
140
200
2048
1.0
70
1.6
100
4096
1024
2.25
140
280
mV
µs
ns
ms
Clock
Cycles
sec
ms
Clock
Cycles
ns
0.004
0.1
3.5
7
0.1
0.4
0.4
3.5
1
15
100
0.4
3.5
3
0.75 x V
CC
0.8
-50
-10
20
50
10
20
mA
V
V
µA
V
mA
V
µA
3
0.3
0.4
V
MAX
UNITS
mV
V
mA
µA
MAX691A/MAX693A/MAX800L/MAX800M
1
4.50
4.25
4.55
4.30
RESET AND WATCHDOG TIMER
MAX691A, MAX800L
Reset Threshold Voltage
MAX693A, MAX800M
MAX800L, T
A
= +25°C, V
CC
falling
MAX800M, T
A
= +25°C, V
CC
falling
Reset Threshold Hysteresis
V
CC
to RESET Delay
LOW LINE-to-RESET
Delay
Reset Active Timeout Period,
Power-up
Internal Oscillator
Reset Active Timeout Period,
Power-up
External Clock (Note 4)
Watchdog Timeout Period,
Internal Oscillator
Watchdog Timeout Period,
External Clock (Note 4)
Minimum Watchdog Input
Pulse Width
RESET
Output Voltage
Long period
Short period
Long period
Short period
V
IL
= 0.8V, V
IH
= 0.75 x V
CC
I
SINK
= 50µA, V
CC
= 1V, VBATT = 0V, V
CC
falling
I
SINK
= 3.2mA, V
CC
= 4.25V
I
SOURCE
= 1.6mA, V
CC
= 5V
100
V
–
RESET
Output Short-Circuit
Output source current
Current
RESET Output Voltage Low
I
SINK
= 3.2mA
(Note 5)
LOW LINE
Output Voltage
LOW LINE
Output
Short-Circuit Current
WDO
Output Voltage
WDO
Output
Short-Circuit Current
WDI Threshold Voltage
(Note 6)
WDI Input Current
I
SINK
= 3.2mA, V
CC
= 4.25V
I
SOURCE
= 1µA, V
CC
= 5V
Output source current
I
SINK
= 3.2mA
I
SOURCE
= 500µA, V
CC
= 5V
Output source current
V
IH
V
IL
WDI = 0V
WDI = V
OUT
_______________________________________________________________________________________
Microprocessor Supervisory Circuits
MAX691A/MAX693A/MAX800L/MAX800M
ELECTRICAL CHARACTERISTICS (continued)
(MAX691A, MAX800L: V
CC
= +4.75V to +5.5V; MAX693A, MAX800M: V
CC
= +4.5V to +5.5V; VBATT = 2.8V, T
A
= T
MIN
to T
MAX
,
unless otherwise noted.)
PARAMETER
POWER-FAIL COMPARATOR
PFI Input Threshold
PFI Leakage Current
PFO
Output Voltage
PFO
Output Short-Circuit
Current
PFI-to-PFO Delay
CHIP-ENABLE GATING
CE
IN Leakage Current
CE
IN-to-CE OUT Resistance
(Note 7)
CE
OUT Short-Circuit Current
(Reset Active)
CE
IN-to-CE OUT Propagation
Delay (Note 8)
CE
OUT Output Voltage High
(Reset Active)
RESET-to-CE OUT Delay
INTERNAL OSCILLATOR
OSC IN Leakage Current
OSC IN Input Pull-Up Current
OSC SEL Input Pull-Up Current
OSC IN Frequency Range
OSC IN External Oscillator
Threshold Voltage
OSC IN Frequency with
External Capacitor
OSC SEL = 0V
OSC SEL = V
OUT
or floating, OSC IN = 0V
OSC SEL = 0V
OSC SEL = 0V
V
IH
V
IL
OSC SEL = 0V, COSC = 47pF
V
OUT
- 0.3
0.10
10
10
50
V
OUT
- 0.6
3.65
100
2.00
±5
100
100
µA
µA
µA
kHz
V
kHz
Disable mode
Enable mode
–
Disable mode,
CE
OUT = 0V
50Ω source impedance driver, C
LOAD
= 50pF
V
CC
= 5V, I
OUT
= -100µA
V
CC
= 0V, VBATT = 2.8V, I
OUT
= 1µA
Power-down
3.5
2.7
12
0.1
±0.005
75
0.75
6
±1
150
2.0
10
µA
Ω
mA
ns
V
µs
I
SINK
= 3.2mA
I
SOURCE
= 1µA, V
CC
= 5V
Output source current
V
IN
= -20mV, V
OD
= 15mV
V
IN
= 20mV, V
OD
= 15mV
3.5
1
15
25
60
100
MAX69_AC/AE/AM, V
CC
= 5V
MAX800_C/E, V
CC
= 5V
1.2
1.225
1.25
1.25
±0.01
1.3
1.275
±25
0.4
V
nA
V
µA
µs
CONDITIONS
MIN
TYP
MAX
UNITS
Note 1:
Either V
CC
or VBATT can go to 0V, if the other is greater than 2.0V.
Note 2:
The supply current drawn by the MAX691A/MAX800L/MAX800M from the battery excluding I
OUT
typically goes to 10µA
when (VBATT - 1V) < V
CC
< VBATT. In most applications, this is a brief period as V
CC
falls through this region.
Note 3:
“+” = battery-discharging current, “--” = battery-charging current.
Note 4:
Although presented as typical values, the number of clock cycles for the reset and watchdog timeout periods are fixed and
do not vary with process or temperature.
Note 5:
RESET is an open-drain output and sinks current only.
Note 6:
WDI is internally connected to a voltage divider between V
OUT
and GND. If unconnected, WDI is driven to 1.6V (typ),
disabling the watchdog function.
Note 7:
The chip-enable resistance is tested with V
CC
= +4.75V for the MAX691A/MAX800L and V
CC
= +4.5V for the
MAX693A/MAX800M.
CE
IN =
CE
OUT = V
CC
/ 2.
Note 8:
The chip-enable propagation delay is measured from the 50% point at
CE
IN to the 50% point at
CE
OUT.
4
_______________________________________________________________________________________
Microprocessor Supervisory Circuits
MAX691A/MAX693A/MAX800L/MAX800M
__________________________________________Typical Operating Characteristics
(T
A
= +25°C, unless otherwise noted.)
V
CC
SUPPLY CURRENT
vs. TEMPERATURE
(NORMAL OPERATING MODE)
MAX691A TOC-01
BATTERY SUPPLY CURRENT
vs. TEMPERATURE
(BATTERY-BACKUP MODE)
MAX691A TOC-02
CHIP-ENABLE ON-RESISTANCE
vs. TEMPERATURE
V
CC
= 4.75V
VBATT = 2.8V
V
CE IN
= V
CC
/2
MAX691A TOC-03
36
V
CC
SUPPLY CURRENT (µA)
CE ON-RESISTANCE (Ω)
34
BATTERY SUPPLY CURRENT (µA)
V
CC
= 5V
VBATT = 2.8V
PFI, CE IN = 0V
2
V
CC
= 5V
VBATT = 2.8V
NO LOAD
120
1.5
100
32
1
80
30
28
0.5
60
26
-60
-30
0
30
60
90
120 150
TEMPERATURE (°C)
0
-60
-30
0
30
60
90
120 150
TEMPERATURE (°C)
40
-60 -30
0
30
60
90
120 150 180
TEMPERATURE (°C)
VBATT to V
OUT
ON-RESISTANCE
vs. TEMPERATURE
MAX691A TOC-04
V
CC
to V
OUT
ON-RESISTANCE
vs. TEMPERATURE
V
CC
-to-V
OUT
ON-RESISTANCE (Ω)
V
CC
= 5V,
VBATT = 0V
MAX691A TOC-05
PFI THRESHOLD
vs. TEMPERATURE
MAX691A TOC-06
20
VBATT-to-V
OUT
ON-RESISTANCE (Ω)
1.2
1.1
1.0
0.9
0.8
0.7
0.6
1.50
1.25
PFI THRESHOLD (V)
1.00
0.75
0.50
0.25
0
V
CC
= +5V,
VBATT = 0V
NO LOAD ON PFO
-60
-30
0
30
60
90
VBATT = 2.0V
15
VBATT = 2.8V
10
VBATT = 4.5V
5
-60
-30
0
30
60
90
TEMPERATURE (°C)
V
CC
= 0V
120 150
-60
-30
0
30
60
90
120 150
120 150
TEMPERATURE (°C)
TEMPERATURE (°C)
RESET THRESHOLD
vs. TEMPERATURE
MAX691A TOC-07
RESET OUTPUT RESISTANCE
vs. TEMPERATURE
MAX691A TOC-08
RESET DELAY
vs. TEMPERATURE
V
CC
= 0V TO 5V STEP
VBATT = 2.8V
MAX691A TOC-09
4.75
4.70
RESET THRESHOLD (V)
4.65
4.60
4.55
4.50
4.45
4.40
4.35
4.30
VBATT = 2.8V
600
RESET OUTPUT RESISTANCE (Ω)
500
400
300
200
100
0
V
CC
= 0V, VBATT = 2.8V
SINKING CURRENT
-60
-30
0
30
60
90
230
220
RESET DELAY (ms)
210
200
190
180
170
MAX691A
MAX800L
V
CC
= 5V, VBATT = 2.8V
SOURCING CURRENT
MAX693A
MAX800M
-60
-30
0
30
60
90
120 150
120 150
-60
-30
0
30
60
90
120 150
TEMPERATURE (°C)
TEMPERATURE (°C)
TEMPERATURE (°C)
_______________________________________________________________________________________
5