MAX6384XS28D1-T ,SC70, Single/Dual Low-Voltage, Low-Power レP Reset CircuitsApplicationsand 3µA at +1.8VComputers Pin Compatible withControllersMAX809/MAX810/MAX803/MAX6326/M ..
MAX6384XS46D3+T ,SC70/µDFN, Single/Dual Low-Voltage, Low-Power µP Reset CircuitsFeaturesThe MAX6381–MAX6390 microprocessor (µP) supervisory ♦ Factory-Set Reset Threshold Voltages ..
MAX6386XS17D3-T ,SC70, Single/Dual Low-Voltage, Low-Power レP Reset CircuitsFeaturesThe MAX6381–MAX6390 microprocessor (µP) supervisory Factory-Set Reset Threshold Voltages R ..
MAX6386XS22D3+T ,SC70/µDFN, Single/Dual Low-Voltage, Low-Power µP Reset CircuitsELECTRICAL CHARACTERISTICS(V = full range, T = -40°C to +125°C, unless otherwise specified. Typical ..
MAX6386XS22D3+T ,SC70/µDFN, Single/Dual Low-Voltage, Low-Power µP Reset CircuitsELECTRICAL CHARACTERISTICS(V = full range, T = -40°C to +125°C, unless otherwise specified. Typical ..
MAX6386XS26D2+T ,SC70/µDFN, Single/Dual Low-Voltage, Low-Power µP Reset CircuitsMAX6381–MAX639019-1839; Rev 5; 7/12SC70/µDFN, Single/Dual Low-Voltage, Low-Power µP Reset Circuits
MB2245BB ,16-bit transceivers with direction pins 3-State
MB2245BB ,16-bit transceivers with direction pins 3-State
MB2374BB ,Dual octal D-type flip-flop; positive-edge trigger (3-State)
MB2374BB ,Dual octal D-type flip-flop; positive-edge trigger (3-State)
MB2374BB ,Dual octal D-type flip-flop; positive-edge trigger (3-State)
MB2543BB ,Dual octal latched transceivers with dual enable 3-State
MAX6384XS23D6-T-MAX6384XS26D4-T-MAX6384XS28D1-T-MAX6386XS17D3-T-MAX6386XS29D2-T-MAX6390XS26D7-T
SC70, Single/Dual Low-Voltage, Low-Power レP Reset Circuits
General DescriptionThe MAX6381–MAX6390 microprocessor (µP) supervisory
circuits monitor power supply voltages from +1.8V to
+5.0V while consuming only 3µA of supply current at
+1.8V. Whenever VCCfalls below the factory-set reset
thresholds, the reset output asserts and remains assert-
ed for a minimum reset timeout period after VCCrises
above the reset threshold. Reset thresholds are available
from +1.58V to +4.63V, in approximately 100mV incre-
ments. Seven minimum reset timeout delays ranging
from 1ms to 1200ms are available.
The MAX6381/MAX6384/MAX6387 have a push-pull
active-low reset output. The MAX6382/MAX6385/
MAX6388 have a push-pull active-high reset output,
and the MAX6383/MAX6386/MAX6389/MAX6390
have an open-drain active-low reset output. The
MAX6384/MAX6385/MAX6386 also feature a
debounced manual reset input (with internal pullup
resistor). The MAX6387/MAX6388/MAX6389 have an
auxiliary input for monitoring a second voltage. The
MAX6390 offers a manual reset input with a longer VCC
reset timeout period (1120ms or 1200ms) and a shorter
manual reset timeout (140ms or 150ms).
The MAX6381/MAX6382/MAX6383 are available in 3-pin
SC70 packages and the MAX6384–MAX6390 are avail-
able in 4-pin SC70 packages.
________________________ApplicationsComputers
Controllers
Intelligent Instruments
Critical µP and µC Power Monitoring
Portable/Battery-Powered Equipment
Dual Voltage Systems
FeaturesFactory-Set Reset Threshold Voltages Ranging
from +1.58V to +4.63V in Approximately 100mV
Increments±2.5% Reset Threshold Accuracy Over
Temperature (-40°C to +125°C)Seven Reset Timeout Periods Available: 1ms,
20ms, 140ms, 280ms, 560ms, 1120ms,
1200ms (min)3 Reset Output Options
Active-Low Push-Pull
Active-High Push-Pull
Active-Low Open-DrainReset Output State Guaranteed Valid
Down to VCC= 1VManual Reset Input (MAX6384/MAX6385/MAX6386)Auxiliary RESETIN
(MAX6387/MAX6388/MAX6389)VCCReset Timeout (1120ms or 1200ms)/Manual
Reset Timeout (140ms or 150ms) (MAX6390)Negative-Going VCCTransient ImmunityLow Power Consumption of 6µA at +3.6V
and 3µA at +1.8VPin Compatible with
MAX809/MAX810/MAX803/MAX6326/MAX6327/
MAX6328/MAX6346/MAX6347/MAX6348,
and MAX6711/MAX6712/MAX6713Tiny 3-Pin SC70 and 4-Pin SC70 Packages
MAX6381–MAX6390
SC70, Single/Dual Low-Voltage,
Low-Power µP Reset Circuits
Pin Configurations19-1839; Rev 1; 04/01
Ordering Information
Ordering Information continuedat end of data sheet.
Typical Operating Circuit appears at end of data sheet.
Selector Guide appears at end of data sheet.
Note:Insert reset threshold suffix (see Reset Threshold table)
after "XR" or "XS". Insert reset timeout delay (see Reset Timeout
Delay table) after "D" to complete the part number. Sample
stock is generally held on standard versions only (see
Standard Versions table). Standard versions have an order
increment requirement of 2500 pieces. Nonstandard versions
have an order increment requirement of 10,000 pieces.
Contact factory for availability of nonstandard versions.
*MAX6390 is available with D4 or D7 timing only.
MAX6381–MAX6390
SC70, Single/Dual Low-Voltage,
Low-Power µP Reset Circuits
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICSStresses 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.
VCC to GND..........................................................-0.3V to +6.0VRESETOpen-Drain Output....................................-0.3V to +6.0V
RESET, RESET (Push-Pull Output).............-0.3V to (VCC+ 0.3V)MR, RESET IN.............................................-0.3V to (VCC+ 0.3V)
Input Current (VCC).............................................................20mA
Output Current (All Pins).....................................................20mA
Continuous Power Dissipation (TA= +70°C)
3-Pin SC70 (derate 2.9mW/°C above +70°C)........235mW
4-Pin SC70 (derate 3.1mW/°C above +70°C)........245mW
Operating Temperature Range.........................-40°C to +125°C
Storage Temperature Range.............................-65°C to +150°C
Lead Temperature (soldering, 10s).................................+300°C
MAX6381–MAX6390
SC70, Single/Dual Low-Voltage,
Low-Power µP Reset Circuits
ELECTRICAL CHARACTERISTICS (continued)
MAX6381–MAX6390
SC70, Single/Dual Low-Voltage,
Low-Power µP Reset Circuits
Typical Operating Characteristics(TA = +25°C, unless otherwise noted.)
MAX6381–MAX6390
SC70, Single/Dual Low-Voltage,
Low-Power µP Reset Circuits
MAX6381–MAX6390
SC70, Single/Dual Low-Voltage,
Low-Power µP Reset Circuits
Detailed Description
RESET OutputA µP reset input starts the µP in a known state. These
µP supervisory circuits assert reset to prevent code
execution errors during power-up, power-down, or
brownout conditions.
Reset asserts when VCCis below the reset threshold;
once VCCexceeds the reset threshold, an internal timer
keeps the reset output asserted for the reset timeout
period. After this interval, reset output deasserts. Reset
output is guaranteed to be in the correct logic state for
VCC≥1V.
Manual Reset Input (MAX6384/
MAX6385/MAX6386/MAX6390)Many µP-based products require manual reset capabil-
ity, allowing the operator, a test technician, or external
logic circuitry to initiate a reset. A logic low on MR
asserts reset. Reset remains asserted while MRis low,
and for the reset active timeout period (tRP) after MR
returns high. This input has an internal 63kΩpullup
resistor (1.35kΩfor MAX6390), so it can be left uncon-
nected if it is not used. MRcan be driven with TTL or
CMOS logic levels, or with open-drain/collector outputs.
Connect a normally open momentary switch from MRto
GND to create a manual-reset function; external
debounce circuitry is not required. If MRis driven from
long cables or if the device is used in a noisy environ-
ment, connecting a 0.1µF capacitor from MRto GND
provides additional noise immunity.
RESET IN Comparator
(MAX6387/MAX6388/MAX6389)RESET IN is compared to an internal +1.27V reference.
If the voltage at RESET IN is less than 1.27V, reset
asserts. Use the RESET IN comparator as a user-
adjustable reset detector or as a secondary power-sup-
ply monitor by implementing a resistor-divider at RESET
IN (shown in Figure 1). Reset asserts when either VCC
or RESET IN falls below its respective threshold volt-
age. Use the following equation to set the threshold:
VINTH= VTHRST (R1/R2 + 1)
where VTHRST= +1.27V. To simplify the resistor selec-
tion, choose a value of R2 and calculate R1:
R1 = R2 [(VINTH/VTHRST) - 1]
Since the input current at RESET IN is 50nA (max),
large values can be used for R2 with no significant loss
in accuracy.
___________Applications Information
Negative-Going VCCTransientsIn addition to issuing a reset to the µP during power-up,
power-down, and brownout conditions, the
MAX6381–MAX6390 are relatively immune to short dura-
tion negative-going VCCtransients (glitches).
The Typical Operating Characteristicssection shows the
Maximum Transient Durations vs. Reset Comparator
Overdrive, for which the MAX6381–MAX6390 do not
generate a reset pulse. This graph was generated using
