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MAX6381XR37D1+中文资料

General Description The 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 V CC falls below the factory-set reset thresholds, the reset output asserts and remains assert-ed for a minimum reset timeout period after V CC rises 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 V CC 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 and6-pinμDFN packages and the MAX6384–MAX6390 are available in 4-pin SC70 and

Features

?Factory-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-Drain

?Reset Output State Guaranteed Valid

Down to V CC= 1V

?Manual Reset Input (MAX6384/MAX6385/MAX6386)

?Auxiliary RESET IN

(MAX6387/MAX6388/MAX6389)

?V CC Reset Timeout (1120ms or 1200ms)/Manual

Reset Timeout (140ms or 150ms) (MAX6390)

?Negative-Going V CC Transient Immunity

?Low Power Consumption of 6μA at +3.6V

and 3μA at +1.8V

?Pin Compatible with

MAX809/MAX810/MAX803/MAX6326/MAX6327/

MAX6328/MAX6346/MAX6347/MAX6348,

and MAX6711/MAX6712/MAX6713

?Tiny 3-Pin/4-Pin SC70 and 6-Pin μDFN Packages

MAX6381–MAX6390 SC70/μDFN, Single/Dual Low-Voltage,

Low-Power μP Reset Circuits ________________________________________________________________Maxim Integrated Products1

Pin Configurations

19-1839; Rev 4; 4/07

Ordering Information

Ordering Information continued at end of data sheet.

Typi cal Operati ng Ci rcui t appears at end of data sheet.

Selector Guide appears at end of data sheet.

after "XR", "XS", or "LT." 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.

+Denotes a lead-free package.

For pricing, delivery, and ordering information,please contact Maxim Direct at 1-888-629-4642,

or visit Maxim’s website at https://www.wendangku.net/doc/2d737591.html,.

Computers

Controllers

Intelligent Instruments

Critical μP and μC

Power Monitoring

Portable/Battery-

Powered Equipment

Dual Voltage Systems

M A X 6381–M A X 6390

SC70/μDFN, Single/Dual Low-Voltage, Low-Power μP Reset Circuits

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(V CC = full range, T A = -40°C to +125°C, unless otherwise specified. Typical values are at T A = +25°C.) (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.

V CC to GND..........................................................-0.3V to +6.0V RESET Open-Drain Output....................................-0.3V to +6.0V RESET , RESET (push-pull output)..............-0.3V to (V CC + 0.3V)MR , RESET IN.............................................-0.3V to (V CC + 0.3V)Input Current (V CC ).............................................................20mA Output Current (all pins).....................................................20mA

Continuous Power Dissipation (T A = +70°C)

3-Pin SC70 (derate 2.9mW/°C above +70°C)..............235mW 4-Pin SC70 (derate 3.1mW/°C above +70°C)..............245mW 6-Pin μDFN (derate 2.1mW/°C above +70°C)..........167.7mW 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/μDFN, Single/Dual Low-Voltage,

Low-Power μP Reset Circuits

_______________________________________________________________________________________3

M A X 6381–M A X 6390

SC70/μDFN, Single/Dual Low-Voltage, Low-Power μP Reset Circuits 4______________________________________________________________________________________

Typical Operating Characteristics

(T A = +25°C, unless otherwise noted.)

215436789-40-105-25203550658095110125

SUPPLY CURRENT vs. TEMPERATURE

(NO LOAD)

TEMPERATURE (°C)

S U P P L Y C U R R E N T (μA )

25

292735333137394143

-40-105-2520355065

8095110125

POWER-DOWN RESET DELAY

vs. TEMPERATURE

TEMPERATURE (°C)

P O W E R -D O W N R E S E T D E L A Y (μs )

0.94

0.980.961.021.001.061.041.08-40-10520-253550658095110125

NORMALIZED POWER-UP RESET TIMEOUT

vs. TEMPERATURE

M A X 6381/90 t o c 03

TEMPERATURE (°C)

N O R M A L I Z E D R E S E T T I M E O U T P E R I O D

0.990

0.985

1.0150.9950.9901.0001.0051.0101.020-40-10520-253550958011065125

M A X 6381/90 t o c 04

TEMPERATURE (°C)

N O R M A L I Z E D R E S E T T

H R E S H O L D NORMALIZED RESET THRESHOLD

vs. TEMPERATURE

00.40.20.8

0.6

1.01.20

63

9

12

OUTPUT-VOLTAGE LOW vs. SINK CURRENT

I SINK (mA)

V O L (V )

01.0

0.52.01.52.53.00

500

750

250

1000

1250

1500

OUTPUT-VOLTAGE HIGH vs. SOURCE CURRENT

I SOURCE (μA)

V O H (V )

4500

1

1000100

10

MAXIMUM TRANSIENT DURATION vs. RESET COMPARATOR OVERDRIVE

15050350250500

200100400300RESET COMPARATOR OVERDRIVE, V TH - V CC (mV)

M A X I M U M T R A N S I E N T D U R A T I O N (μs )

3.5

3.93.7

4.54.34.14.74.9

5.35.15.5

-40-105-25203550658095110125

RESET IN TO RESET DELAY

vs. TEMPERATURE

M A X 6381/90 t o c 08

TEMPERATURE (°C)

R E S E T I N D E L A Y (μs )

MAX6381–MAX6390

SC70/μDFN, Single/Dual Low-Voltage,

Low-Power μP Reset Circuits

Pin Description

M A X 6381–M A X 6390

SC70/μDFN, Single/Dual Low-Voltage, Low-Power μP Reset Circuits 6_______________________________________________________________________________________

Detailed Description

RESET Output

A 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 V CC is below the reset threshold;once V CC exceeds 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 V CC ≥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 MR is low,and for the reset active timeout period (t RP ) after MR returns high. This input has an internal 63k ?pullup resistor (1.56k ?for MAX6390), so it can be left uncon-nected if it is not used. MR can be driven with TTL or CMOS logic levels, or with open-drain/collector outputs.Connect a normally open momentary switch from MR to G ND to create a manual-reset function; external debounce circuitry is not required. If MR is driven from long cables or if the device is used in a noisy environ-ment, connecting a 0.1μF capacitor from MR to G ND 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 V CC or RESET IN falls below its respective threshold volt-age. Use the following equation to set the threshold:

V INTH = V THRST (R1/R2 + 1)where V THRST = +1.27V. To simplify the resistor selec-tion, choose a value of R2 and calculate R1:

R1 = R2 [(V INTH /V THRST ) - 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 V CC Transients

In 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 V CC transients (glitches).

The Typical Operating Characteristics section 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

a negative-going pulse applied to V CC , starting above the actual reset threshold and ending below it by the magnitude indicated (reset comparator overdrive). The graph indicates the typical maximum pulse width a neg-ative-going V CC transient may have without causing a reset pulse to be issued. As the magnitude of the tran-sient increases (goes farther below the reset threshold),the maximum allowable pulse width decreases. A 0.1μF capacitor mounted as close as possible to V CC provides additional transient immunity.

Ensuring a Valid RESET Output Down to V CC = 0V

The MAX6381–MAX6390 are guaranteed to operate properly down to V CC = 1V. In applications that require valid reset levels down to V CC = 0V, a pulldown resistor to active-low outputs (push/pull only, Figure 2) and a pullup resistor to active-high outputs (push/pull only)will ensure that the reset line is valid while the reset out-put can no longer sink or source current. This scheme

does not work with the open-drain outputs of the MAX6383/MAX6386/MAX6389/MAX6390. The resistor value used is not critical, but it must be small enough not to load the reset output when V CC is above the reset threshold. For most applications, 100k ?is ade-quate.

MAX6381–MAX6390

SC70/μDFN, Single/Dual Low-Voltage,

Low-Power μP Reset Circuits

_______________________________________________________________________________________7

M A X 6381–M A X 6390

SC70/μDFN, Single/Dual Low-Voltage, Low-Power μP Reset Circuits 8

_______________________________________________________________________________________

Selector Guide

Ordering Information (continued)

Note:Insert reset threshold suffix (see Reset Threshold table)after "XR", "XS", or "LT." 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.+Denotes a lead-free package.

MAX6381–MAX6390

SC70/μDFN, Single/Dual Low-Voltage,

Low-Power μP Reset Circuits

_______________________________________________________________________________________9

Chip Information

TRANSISTOR COUNT: 647PROCESS: BiCMOS

Pin Configurations (continued)

M A X 6381–M A X 6390

SC70/μDFN, Single/Dual Low-Voltage, Low-Power μP Reset Circuits 10______________________________________________________________________________________

Package Information

(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,go to https://www.wendangku.net/doc/2d737591.html,/packages .)

MAX6381–MAX6390

SC70/μDFN, Single/Dual Low-Voltage,

Low-Power μP Reset Circuits

______________________________________________________________________________________11

Package Information (continued)

(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,go to https://www.wendangku.net/doc/2d737591.html,/packages .)

M A X 6381–M A X 6390

SC70/μDFN, Single/Dual Low-Voltage, Low-Power μP Reset Circuits 12______________________________________________________________________________________

Package Information (continued)

(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,go to https://www.wendangku.net/doc/2d737591.html,/packages .)

SC70/μDFN, Single/Dual Low-Voltage,

Low-Power μP Reset Circuits

Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.

Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600____________________13?2007 Maxim Integrated Products

is a registered trademark of Maxim Integrated Products, Inc.

MAX6381–MAX6390

Package Information (continued)

(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,go to https://www.wendangku.net/doc/2d737591.html,/packages .)

Revision History

Pages changed at Rev 4: Title on all pages, 1, 2, 5,

7–13

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