MAX807LEPE ,Full-featured microprocessor supervisory circuit with +-1.5% reset accuracy. Reset threshold (typ) 4.675VApplicationsPFI1 OUT16ComputersBATT OKPFO 2 15VControllers CC BATT3 14Intelligent Instruments WDI4 ..
MAX807LEWE ,Full-featured microprocessor supervisory circuit with +-1.5% reset accuracy. Reset threshold (typ) 4.675VApplicationsPFI1 OUT16ComputersBATT OKPFO 2 15VControllers CC BATT3 14Intelligent Instruments WDI4 ..
MAX807MCWE ,Full-featured microprocessor supervisory circuit with +-1.5% reset accuracy. Reset threshold (typ) 4.425VMAX807L/M/N19-0433; Rev 0; 9/95Full-Featured µP Supervisory Circuit with±1.5% Reset Accuracy_______ ..
MAX807MCWE+ ,Full-Featured µP Supervisory Circuit with ±1.5% Reset AccuracyApplicationsV BATTCC 314ComputersWDI4 MAX807 13 BATT ONControllersGND CE IN5 12Intelligent Instrume ..
MAX807MEWE ,Full-featured microprocessor supervisory circuit with +-1.5% reset accuracy. Reset threshold (typ) 4.425VFeaturesThe MAX807 microprocessor (µP) supervisory circuit' Precision 4.675V (MAX807L) or 4.425Vred ..
MAX807MEWE+ ,Full-Featured µP Supervisory Circuit with ±1.5% Reset AccuracyMAX807L/M/N19-0433; Rev 4; 11/05Full-Featured µP Supervisory Circuit with±1.5% Reset Accuracy
MB71A38-25 , PROGRAMMABLE SCHOTTKY 16384-BIT READ ONLY MEMORY
MB8117800A-60 ,2 M X 8 BIT FAST PAGE MODE DYNAMIC RAMapplications where very low power dissipation and high bandwidth are basic requirements of the desi ..
MB81464- ,MOS 262144 Bit DRAMfeatures page mode which allows high speed
random access of up to 256 bits within the same tow.
..
MAX807LCPE-MAX807LCWE-MAX807LEPE-MAX807LEWE-MAX807MCWE-MAX807MEWE-MAX807NCPE-MAX807NCWE-MAX807NEWE
Full-featured microprocessor supervisory circuit with +-1.5% reset accuracy. Reset threshold (typ) 4.675V
MAX807L/M/N
Full-Featured µP Supervisory Circuit with
±1.5% Reset Accuracy
________________________________________________________________Maxim Integrated Products1
Call toll free 1-800-998-8800 for free samples or literature.19-0433; Rev 0; 9/95
_______________General DescriptionThe MAX807 microprocessor (µP) supervisory circuit
reduces the complexity and number of components
needed to monitor power-supply and battery-control func-
tions in µP systems. A 70µA supply current makes the
MAX807 ideal for use in portable equipment, while a 2ns
chip-enable propagation delay and 250mA output current
capability (20mA in battery-backup mode) make it suit-
able for larger, higher-performance equipment.
The MAX807 comes in 16-pin DIP and SO packages, and
provides the following functions:µP reset. The active-low RESEToutput is asserted dur-
ing power-up, power-down, and brownout conditions,
and is guaranteed to be in the correct state for VCC
down to 1V.Active-high RESET output.Manual-reset input.Two-stage power-fail warning. A separate low-line
comparator compares VCCto a threshold 52mV above
the reset threshold. This low-line comparator is more
accurate than those in previous µP supervisors.
5) Backup-battery switchover for CMOS RAM, real-time
clocks, µPs, or other low-power logic.Write protection of CMOS RAM or EEPROM.
7) 2.275V threshold detector—provides for power-fail
warning and low-battery detection, or monitors a
power supply other than +5V.BATT OK status flag indicates that the backup-battery
voltage is above 2.275V.Watchdog-fault output—asserted if the watchdog input
has not been toggled within a preset timeout period.
________________________ApplicationsComputers
Controllers
Intelligent Instruments
Critical µP Power Monitoring
Portable/Battery-Powered Equipment
____________________________FeaturesPrecision 4.675V (MAX807L) or 4.425V
(MAX807M), or 4.575V (MAX807N) Voltage
Monitoring200ms Power OK / Reset Time DelayRESETand RESET OutputsIndependent Watchdog Timer1µA Standby CurrentPower Switching:
250mA in VCCMode
20mA in Battery-Backup ModeOn-Board Gating of Chip-Enable Signals:
2ns CE Gate Propagation DelayMaxCap™and SuperCap™CompatibleVoltage Monitor for Power-Fail Backup-Battery MonitorGuaranteed RESETValid to VCC= 1V±1.5% Low-line Threshold Accuracy 52mV above
Reset Threshold
__________________Pin Configuration
Ordering Information and Typical Operating Circuit appear at end of data sheet.SuperCap is a trademark of Baknor Industries. MaxCap is a trademark of The Carborundum Corp.
MAX807L/M/N
Full-Featured µP Supervisory Circuit with
±1.5% Reset Accuracy_______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS(VCC= 4.60V to 5.5V for the MAX807L, VCC= 4.50V to 5.5V for the MAX807N, VCC= 4.35V to 5.5V for the MAX807M,
VBATT= 2.8V, VPFI= 0V, TA= TMINto TMAX. Typical values are tested with VCC= 5V and TA= +25°C, unless otherwise noted.)
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.
Input Voltages (with respect to GND)
VCC..........................................................................-0.3V to 6V
VBATT.......................................................................-0.3V to 6V
All Other Inputs......................................-0.3V to (VOUT+ 0.3V)
Input Current
VCCPeak...........................................................................1.0A
VCCContinuous.............................................................500mA
IBATTPeak......................................................................250mA
IBATTContinuous.............................................................50mA
GND.................................................................................50mA
All Other Inputs................................................................50mA
Continuous Power Dissipation (TA= +70°C)
Plastic DIP (derate 10.53mW/°C above +70°C)...........842mW
Wide SO (derate 9.52mW/°C above +70°C).................762mW
CERDIP (derate 10.00mW/°C above +70°C)................800mW
Operating Temperature Ranges
MAX807_C_E.......................................................0°C to +70°C
MAX807_E_E....................................................-40°C to +85°C
MAX807_MJE.................................................-55°C to +125°C
Storage Temperature Range.............................-65°C to +160°C
Lead Temperature (soldering, 10sec).............................+300°C
MAX807L/M/N
Full-Featured µP Supervisory Circuit with
±1.5% Reset Accuracy
_______________________________________________________________________________________3
ELECTRICAL CHARACTERISTICS (continued)(VCC= 4.60V to 5.5V for the MAX807L, VCC= 4.50V to 5.5V for the MAX807N, VCC= 4.35V to 5.5V for the MAX807M,
VBATT= 2.8V, VPFI= 0V, TA= TMINto TMAX. Typical values are tested with VCC= 5V and TA= +25°C, unless otherwise noted.)
MAX807L/M/N
Full-Featured µP Supervisory Circuit with
±1.5% Reset Accuracy_______________________________________________________________________________________
Note 1:Either VCCor VBATTcan go to 0V, if the other is greater than 2.0V.
Note 2:The supply current drawn by the MAX807 from the battery (excluding IOUT) typically goes to 15µA when (VBATT- 0.1V)
< VCC< VBATT. In most applications, this is a brief period as VCCfalls through this region (see Typical Operating Characteristics).
Note 3:“+”= battery discharging current, “-”= battery charging current.
Note 4:WDI is internally connected to a voltage divider between VCCand GND. If unconnected, WDI is driven to 1.8V (typical),
disabling the watchdog function.
Note 5:Overdrive (VOD) is measured from center of hysteresis band.
Note 6:The chip-enable resistance is tested with VCEIN= VCC/2, and ICEIN= 1mA.
Note 7:The chip-enable propagation delay is measured from the 50% point at CEIN to the 50% point at CEOUT.
ELECTRICAL CHARACTERISTICS (continued)(VCC= 4.60V to 5.5V for the MAX807L, VCC= 4.50V to 5.5V for the MAX807N, VCC= 4.35V to 5.5V for the MAX807M,
VBATT= 2.8V, VPFI= 0V, TA= TMINto TMAX. Typical values are tested with VCC= 5V and TA= +25°C, unless otherwise noted.)
MAX807L/M/N
Full-Featured µP Supervisory Circuit with
±1.5% Reset Accuracy
_______________________________________________________________________________________5VCC SUPPLY CURRENT vs. TEMPERATURE
(NORMAL OPERATING MODE)
MAX807-01
TEMPERATURE (°C)
SUPPLY CURRENT (100-4040120080
BATTERY SUPPLY CURRENT vs.
TEMPERATURE (BATTERY-BACKUP MODE)
MAX807-02
TEMPERATURE (°C)
BATTERY SUPPLY CURRENT (100-4040120080
CHIP-ENABLE PROPAGATION DELAY
vs. TEMPERATURE
MAX807-03
TEMPERATURE (°C)
PROPAGATION DELAY (ns)100-4040120080
BATT-to-OUT ON-RESISTANCE
vs. TEMPERATURE
MAX807-04
TEMPERATURE (°C)
BATT-to-OUT ON-RESISTANCE (100-4040120080
RESET THRESHOLD
vs. TEMPERATURE
MAX807-07
TEMPERATURE (°C)
RESET THRESHOLD (V)100-4040120080
VCC-to-OUT ON-RESISTANCE
vs. TEMPERATURE
MAX807-05
TEMPERATURE (°C)
-to-OUT ON-RESISTANCE (100-40401200802.340
PFI THRESHOLD
vs. TEMPERATURE (VPFI FALLING)
MAX807-06
TEMPERATURE (°C)
PFI THRESHOLD (V)100-4040120080
RESET TIMEOUT PERIOD
vs. TEMPERATURE (VCC RISING)
MAX807-08
TEMPERATURE (°C)
RESET TIMEOUT PERIOD (ms)100-4040120080
LOW LINE -to-RESET THRESHOLD
vs. TEMPERATURE (VCC FALLING)
MAX807-09
TEMPERATURE (°C)
LOW LINE-to-RESET THRESHOLD (mV)100-4040120080
__________________________________________Typical Operating Characteristics(VCC= 5V, VBATT= 2.8V, PFI = 0V, no load, TA= +25°C, unless otherwise noted.)
MAX807L/M/N
Full-Featured µP Supervisory Circuit with
±1.5% Reset Accuracy_______________________________________________________________________________________
____________________________Typical Operating Characteristics (continued)(VCC= 5V, VBATT= 2.8V, PFI = 0V, no load, TA= +25°C, unless otherwise noted.)
4.40
LOW LINE THRESHOLD
vs. TEMPERATURE (VCC RISING)
MAX807-10
TEMPERATURE (°C)
LOW LINE THRESHOLD (V)100-4040120080
LOW LINE COMPARATOR PROPAGATION
DELAY vs. TEMPERATURE (VCC FALLING)
MAX807-11
TEMPERATURE (°C)
LOW LINE COMPARATOR PROP. DELAY (100-4040120080
RESET COMPARATOR PROPAGATION
DELAY vs. TEMPERATURE (VCC FALLING)
MAX807-12
TEMPERATURE (°C)
RESET COMPARATOR PROP. DELAY (100-4040120080
BATTERY CURRENT
vs. INPUT SUPPLY VOLTAGE
MAX807-13
VCC (V)
BATTERY CURRENT (
VCC-to-OUT vs.
OUTPUT CURRENT
MAX807-16
IOUT (mA)
-VOUT (mV)50100
CHIP-ENABLE PROPAGATION DELAY
vs. CE OUT LOAD CAPACITANCEMAX807-14
CLOAD (pF)
PROPAGATION DELAY (ns)
BATT-to-OUT vs.
OUTPUT CURRENT
MAX807-15
IOUT (mA)
BATT-to-OUT (mV)
MAXIMUM TRANSIENT DURATION vs.
RESET COMPARATOR OVERDRIVE
MAX807-17
RESET COMPARATOR OVERDRIVE (mV)
MAXIMUM TRANSIENT DURATION (
MAX807L/M/N
Full-Featured µP Supervisory Circuit with
±1.5% Reset Accuracy
_______________________________________________________________________________________7
______________________________________________________________Pin Description
_______________Detailed DescriptionThe MAX807 microprocessor (µP) supervisory circuit
provides power-supply monitoring, backup-battery
switchover, and program execution watchdog functions
in µP systems (Figure 1). Use of BiCMOS technology
results in an improved 1.5% reset-threshold precision,
while keeping supply currents typically below 70µA.
The MAX807 is intended for battery-powered applica-
tions that require high reset-threshold precision, allow-
ing a wide power-supply operating range while
preventing the system from operating below its speci-
fied voltage range.
RESETand RESET OutputsThe MAX807’s RESEToutput ensures that the µP pow-
ers up in a known state, and prevents code execution
errors during power-down and brownout conditions. It
accomplishes this by resetting the µP, terminating pro-
gram execution when VCCdips below the reset thresh-
old or MRis pulled low. Each time RESETis asserted it
stays low for the 200ms reset timeout period, which is
set by an internal timer to ensure the µP has adequate
time to return to an initial state. Any time VCCgoes
below the reset threshold before the reset timeout peri-
od is completed, the internal timer restarts. The watch-
dog timer can also initiate a reset if WDOis connected
to MR. See the Watchdog Inputsection.
MAX807L/M/N
Full-Featured µP Supervisory Circuit with
±1.5% Reset Accuracy_______________________________________________________________________________________Figure 1. Block Diagram
