
General Description
The MAX803/MAX809/MAX810 are microprocessor (µP)
supervisory circuits used to monitor the power supplies
in µP and digital systems. They provide excellent circuit
reliability and low cost by eliminating external components and adjustments when used with +5V, +3.3V,
+3.0V, or +2.5V-powered circuits.
These circuits perform a single function: they assert a
reset signal whenever the VCCsupply voltage declines
below a preset threshold, keeping it asserted for at
least 140ms after VCChas risen above the reset threshold. Reset thresholds suitable for operation with a variety of supply voltages are available.
The MAX803 has an open-drain output stage, while the
MAX809/MAX810 have push-pull outputs. The
MAX803’s open-drain RESET output requires a pull-up
resistor that can be connected to a voltage higher than
VCC. The MAX803/MAX809 have an active-low RESET
output, while the MAX810 has an active-high RESET
output. The reset comparator is designed to ignore fast
transients on VCC, and the outputs are guaranteed to
be in the correct logic state for VCCdown to 1V.
Low supply current makes the MAX803/MAX809/
MAX810 ideal for use in portable equipment. The
MAX803 is available in a 3-pin SC70 package, and the
MAX809/MAX810 are available in 3-pin SC70 or SOT23
packages.
Applications
Computers
Controllers
Intelligent Instruments
Critical µP and µC Power Monitoring
Portable/Battery-Powered Equipment
Automotive
____________________________Features
♦ Precision Monitoring of +2.5V, +3V, +3.3V, and
+5V Power-Supply Voltages
♦ Fully Specified Over Temperature
♦ Available in Three Output Configurations
Open-Drain RESET Output (MAX803)
Push-Pull RESET Output (MAX809)
Push-Pull RESET Output (MAX810)
♦ 140ms min Power-On Reset Pulse Width
♦ 12µA Supply Current
♦ Guaranteed Reset Valid to VCC= +1V
♦ Power Supply Transient Immunity
♦ No External Components
♦ 3-Pin SC70 and SOT23 Packages
MAX803L/M/R/S/T/Z, MAX809J/L/M/R/S/T/Z, MAX810L/M/R/S/T/Z
3-Pin Microprocessor Reset Circuits
________________________________________________________________ Maxim Integrated Products 1
Pin Configuration
Typical Operating Circuit
19-0344; Rev 4; 12/99
Note: These parts are offered in 2.5k or 10k reels, and must be
ordered in 2.5k or 10k increments. Order MAX803_EXR-T for
2.5k reels and MAX803_EXR-T10 for 10k reels. Insert the
desired suffix letter from the Selector Guide into the blank to
complete the part number. All versions of these products may
not be available at the time of announcement. Contact factory for
availability.
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800.
For small orders, phone 1-800-835-8769.
3 SC70-3-40°C to +105°CMAX803_EXR-T10
3 SC70-3
PIN-PACKAGETEMP. RANGE
-40°C to +105°C
MAX803_EXR-T
PART
3 SC70-3-40°C to +105°CMAX809_EXR-T10
3 SC70-3-40°C to +105°C
MAX809_EXR-T
3 SOT23-3-40°C to +105°CMAX809_EUR-T10
3 SOT23-3-40°C to +105°CMAX809_EUR-T
3 SC70-3-40°C to +105°CMAX810_EXR-T10
3 SC70-3-40°C to +105°C
MAX810_EXR-T
3 SOT23-3-40°C to +105°CMAX810_EUR-T10
3 SOT23-3-40°C to +105°CMAX810_EUR-T
Ordering Information
查询MAX803LEXR-T供应商查询MAX803LEXR-T供应商
V
CC
RESET
INPUT
V
CC
µP
V
CC
MAX803
MAX809
RESET
R
PULL-UP
*
TOP VIEW
1
GND
MAX803
MAX809
MAX810
V
3
CC
2
SC70-3/SOT23-3
*MAX803 ONLY
GND
GND
( ) ARE FOR MAX810.
MAX803 AVAILABLE IN SC70-3 ONLY.
RESET (RESET)

MAX803L/M/R/S/T/Z, MAX809J/L/M/R/S/T/Z, MAX810L/M/R/S/T/Z
3-Pin Microprocessor Reset Circuits
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(VCC= full range, TA= -40°C to +105°C, unless otherwise noted. Typical values are at TA= +25°C, VCC= 5V for L/M/J versions, V
CC
= 3.3V for T/S versions, VCC= 3V for R version, and VCC= 2.5V for Z version.) (Note 1)
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)
VCC....................................................................-0.3V to +6.0V
RESET, RESET (push-pull) .....................-0.3V to (V
CC
+ 0.3V)
RESET (open drain)...........................................-0.3V to +6.0V
Input Current, V
CC
..............................................................20mA
Output Current, RESET, RESET ..........................................20mA
Rate of Rise, V
CC
............................................................100V/µs
Continuous Power Dissipation (T
A
= +70°C)
3-Pin SC70 (derate 2.17mW/°C above +70°C)............174mW
3-Pin SOT23 (derate 4mW/°C above +70°C)...............320mW
Operating Temperature Range .........................-40°C to +105°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
TA= -40°C to
+85°C
TA= -40°C to +105°C
TA= 0°C to +70°C
TA= +85°C to
+105°C
MAX8_ _Z
(SC70 only)
TA= -40°C to
+85°C
VCC< 3.6V, MAX8_ _R/S/T
TA= +85°C to
+105°C
MAX8_ _L
CONDITIONS
2.21 2.45
2.25 2.38
2.28 2.32 2.35
2.50 2.76
4.50 4.75
V
4.56 4.63 4.70
V
TH
Reset Threshold
24 60
I
CC
Supply Current (SOT23)
1.2 5.5
V
1.0 5.5
VCCRange
µA
75
75
12 30
16 35
I
CC
Supply Current (SC70)
VCC< 5.5V, MAX8_ _L/M
VCC< 3.6V, MAX8_ _R/S/T
VCC< 5.5V, MAX8_ _L/M
VCC< 3.6V, MAX8_ _R/S/T/Z
17 50
100
100
UNITSMIN TYP MAXSYMBOLPARAMETER
VCC< 5.5V, MAX8_ _J/L/M
VCC< 5.5V, MAX8_ _L/M
MAX8_ _S
2.89 2.93 2.96TA= +25°C
VCC< 3.6V, MAX8_ _R/S/T/Z
TA= +25°C
TA= -40°C to +85°C
MAX8_ _M
4.25 4.50
2.85 3.00TA= -40°C to +85°C
MAX8_ _R
2.55 2.70
2.59 2.63 2.66
2.78 3.08TA= +85°C to +105°C
TA= +25°C
TA= -40°C to +85°C
4.31 4.38 4.45
4.40 4.86TA= +85°C to +105°C
TA= +25°C
TA= -40°C to +85°C
MAX809J
(SOT only)
3.93 4.00 4.06
4.16 4.56TA= +85°C to +105°C
TA= +25°C
3.89 4.10TA= -40°C to +85°C
3.80 4.20TA= +85°C to +105°C
MAX8_ _T
2.92 3.23
3.00 3.15
3.04 3.08 3.11TA= +25°C
TA= -40°C to +85°C
TA= +85°C to +105°C
TA= +85°C to +105°C
TA= +25°C
TA= -40°C to +85°C
TA= +85°C to +105°C

MAX803L/M/R/S/T/Z, MAX809J/L/M/R/S/T/Z, MAX810L/M/R/S/T/Z
3-Pin Microprocessor Reset Circuits
_______________________________________________________________________________________ 3
Note 1: Production testing done at TA= +25°C; limits over temperature guaranteed by design only.
Note 2: RESET output for MAX803/MAX809; RESET output for MAX810.
TA= -40°C to +85°C
TA= +85°C to +105°C
TA= -40°C to +85°C
VCC= VTHto (VTH- 100mV)
CONDITIONS
140 240 460
Reset Active Timeout Period
(SC70)
ms
100 840
140 240 560
Reset Active Timeout Period
(SOT23)
µs20VCCto Reset Delay (Note 2)
ppm/°C30Reset Threshold Tempco
UNITSMIN TYP MAXSYMBOLPARAMETER
TA= +85°C to +105°C
VCC= VTHmax, I
SINK
= 3.2mA,
MAX810L/M
VCC= VTHmax, I
SINK
= 1.2mA,
MAX810R/S/T/Z
VCC> VTHmax, I
SOURCE
= 800µA,
MAX809J/L/M
V
CC
> VTHmax, I
SOURCE
= 500µA,
MAX809R/S/T/Z
VCC= VTHmin, I
SINK
= 1.2mA,
MAX803R/S/T/Z, MAX809R/S/T/Z
VCC= VTHmin, I
SINK
= 3.2mA,
MAX803L/M, MAX809J/L/M
VCC> VTH, RESET deasserted
VCC> 1.0V, I
SINK
= 50µA
1.8V < VCC< VTHmin, I
SOURCE
= 150µA
µA1
RESET Open-Drain Output
Leakage Current (MAX803)
V0.8V
CC
V
OH
RESET Output Voltage High
(push-pull active high, MAX810)
ms
100 840
0.4
V
0.3
V
OL
RESET Output Voltage Low
(push-pull active high, MAX810)
VCC- 1.5
V
0.8V
CC
V
OH
RESET Output Voltage High
(push-pull active low, MAX809)
V
0.3
V
OL
RESET Output Voltage Low
(push-pull active low and opendrain active-low, MAX803 and
MAX809)
0.4
0.3
0
POWER-DOWN RESET DELAY vs.
TEMPERATURE (MAX8_ _R/S/T/Z)
80
100
MAX803-TOC3
TEMPERATURE (°C)
POWER-DOWN RESET DELAY (µs)
40
20
60
-40
85
20
-20
0
60
40
VOD = VTH - V
CC
VOD = 20mV
VOD = 10mV
VOD = 200mV
VOD = 100mV
Typical Operating Characteristics
(VCC= full range, TA= -40°C to +105°C, unless otherwise noted. Typical values are at TA= +25°C, VCC= +5V for L/M/J versions,
V
CC
= +3.3V for T/S versions, VCC= +3V for R version, and VCC= +2.5V for Z version.)
ELECTRICAL CHARACTERISTICS (continued)
(VCC= full range, TA= -40°C to +105°C, unless otherwise noted. Typical values are at TA= +25°C, VCC= 5V for L/M/J versions, V
CC
= 3.3V for T/S versions, VCC= 3V for R version, and VCC= 2.5V for Z version.) (Note 1)
-40 20 40
-20 0 60 85
SUPPLY CURRENT vs. TEMPERATURE
(SC70 PACKAGE, NO LOAD)
MAX803 toc01
TEMPERATURE (°C)
SUPPLY CURRENT (µA)
0
5
10
15
MAX8_ _R/S/T, VCC = 3.3V
MAX8_ _L/M/R/S/T/Z, VCC = 1V
MAX8_ _Z, VCC = 2.5V
MAX8_ _L/M, VCC = 5V