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MAX5091BASA+T中文资料

General Description

The MAX5091 high-voltage linear regulator is designed to operate from a +5V to +28V input voltage, and with-stands up to 40V transients. The device consumes only 45μA of quiescent current at 100μA output current. The MAX5091 delivers up to 100mA of output current with low 50mV maximum dropout voltage. The MAX5091provides an active-low open-drain microprocessor RESET output. The reset timeout period is programma-ble and can be set with an external capacitor. The MAX5091 includes an uncommitted comparator for input voltage monitoring/power-fail indication. The device is available with a fixed +5V (MAX5091A) or +3.3V (MAX5091B) output. The MAX5091 is short-cir-cuit protected and includes thermal shutdown.

The MAX5091 operates over the -40°C to +125°C auto-motive temperature range and is available in 8-pin,thermally enhanced TDFN and SO-EP packages.

Applications

Features

?+5V to +28V Wide Operating Input Voltage Range ?Withstands 40V Input Voltage Transients ?Guaranteed 100mA Output Current

?45μA Typical Quiescent Current at 100μA Output Current ?Preset +5V (MAX5091A) or +3.3V (MAX5091B)Output Voltage ?Stable with Only 10μF Output Capacitance ?RESET Output with Adjustable Timeout Period ?Uncommitted Comparator for Voltage Monitoring/Power-Fail Indication ?Output Overload and Short-Circuit Protection ?Thermal Shutdown

?Available in 8-Pin TDFN (1.95W at T A = +70°C) and 8-Pin SO (1.5W at T A = +70°C)?Operates Over -40°C to +125°C Automotive Temperature Range

MAX5091

28V , 100mA, Low-Quiescent-Current LDO with Reset and Power-Fail Input/Output

Maxim Integrated Products

Pin Configurations

Ordering Information

Typical Application Circuit

19-0654; Rev 0; 11/06

For pricing, delivery, and ordering information,please contact Maxim/Dallas Direct!at 1-888-629-4642, or visit Maxim’s website at https://www.wendangku.net/doc/1813023119.html,.

Note:All devices specified for -40°C to +125°C operating temperature range.+Denotes lead-free package. *EP = Exposed paddle.

Automotive Industrial

Home Security/Safety Telecom/Networking

M A X 5091

28V , 100mA, Low-Quiescent-Current LDO with Reset and Power-Fail Input/Output 2_______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS (MAX5091A)

= +14V, V = 5V, EN unconnected, T = T = -40°C to +125°C, C = 10μF, C = 10μF, unless otherwise noted. Typical 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 S to GND ..............................................................-0.3V to +28V V S to GND (t ≤1s)..................................................-0.3V to +40V V OUT to GND..........................................................-0.3V to +20V V S to OUT...............................................................-0.3V to +28V RES , SO to GND.....................................................-0.3V to +20V RES , SO Output Sink Current................................................5mA V OUT Short Circuit (V S ≤16V)…………......................Continuous EN, SI to GND.........................................................-0.3V to +12V CT to GND.............................-0.3V to the lower of V OUT or +12V

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

8-Pin SO-EP (derate 19.2mW/°C above +70°C).........1538mW*Thermal Resistance (θJA )................................................52°C/W Thermal Resistance (θJC )..................................................6°C/W 8-Pin TDFN-EP (derate 24.4mW/°C above +70°C).....1951mW**Thermal Resistance (θJA )................................................41°C/W Thermal Resistance (θJC )...............................................8.3°C/W Operating Junction Temperature Range...........-40°C to +125°C Maximum Junction Temperature.....................................+150°C Storage Temperature Range.............................-60°C to +150°C Lead Temperature (soldering, 10s).................................+300°C

*As per JEDEC51 Standard (single-layer board).**As per JEDEC51 Standard (multilayer board).

MAX5091

28V , 100mA, Low-Quiescent-Current LDO with Reset and Power-Fail Input/Output

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ELECTRICAL CHARACTERISTICS (MAX5091A) (continued)

(V S = +14V, V OUT = 5V, EN unconnected, T A = T J = -40°C to +125°C, C IN = 10μF, C OUT = 10μF, unless otherwise noted. Typical specifications are at T A = +25°C.) (Note 1)

M A X 5091

28V , 100mA, Low-Quiescent-Current LDO with Reset and Power-Fail Input/Output 4_______________________________________________________________________________________

ELECTRICAL CHARACTERISTICS (MAX5091B)

= +14V, V = 3.3V, EN unconnected, T = T = -40°C to +125°C, C = 10μF, C = 10μF, unless otherwise noted. Typical

MAX5091

28V , 100mA, Low-Quiescent-Current LDO with Reset and Power-Fail Input/Output

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Note 1:Limits at T A = -40°C are guaranteed by design and not production tested.

Note 2:Maximum output current is limited by the power dissipation capability of the package.

ELECTRICAL CHARACTERISTICS (MAX5091B) (continued)

(V S = +14V, V OUT = 3.3V, EN unconnected, T A = T J = -40°C to +125°C, C IN = 10μF, C OUT = 10μF, unless otherwise noted. Typical specifications are at T A = +25°C.) (Note 1)

Typical Operating Characteristics

(Typical Application Circuit , V S = +14V, C IN = 10μF, C OUT = 10μF, V SI = 0V, V EN = +2.4V, V OUT = +5V, T A = +25°C, unless other-wise noted.)

OUTPUT VOLTAGE vs. INPUT VOLTAGE

V S (V)

V O U T (V )

3456

OUTPUT VOLTAGE vs. INPUT VOLTAGE

V S (V)

V O U T (V )

OUTPUT VOLTAGE vs. OUTPUT CURRENT

I OUT (mA)

V O U T (V )

10.1

4.92

4.944.96

4.98

5.00

5.025.044.90

0.01

100

M A X 5091

28V , 100mA, Low-Quiescent-Current LDO with Reset and Power-Fail Input/Output 6_______________________________________________________________________________________

Typical Operating Characteristics (continued)

(Typical Application Circuit , V S = +14V, C IN = 10μF, C OUT = 10μF, V SI = 0V, V EN = +2.4V, V OUT = +5V, T A = +25°C, unless other-wise noted.)

OUTPUT VOLTAGE vs. TEMPERATURE

TEMPERATURE (°C)

V O U T (V )110

-15

4.9254.9504.975

5.0005.0255.0504.900

-40

135

QUIESCENT CURRENT vs. INPUT VOLTAGE

V S (V)

I Q (μA )

10010001

QUIESCENT CURRENT vs. INPUT VOLTAGE

V S (V)

I Q (μA )

100

1000

1RESET OUTPUT LOW

vs. TEMPERATURE

TEMPERATURE (°C)

R E S E T O U T P U T L O W (V

)

1109580655035205-10-250.05

0.10

0.15

0.200.25

-40125

QUIESCENT CURRENT vs. OUTPUT CURRENT

I OUT (mA)

I Q

(m A )

0.1

110

0.01

0.1

100

SHUTDOWN SUPPLY CURRENT

vs. INPUT VOLTAGE

V S (V)

I S H D N (μA )

2010

SHUTDOWN SUPPLY CURRENT

vs. TEMPERATURE

TEMPERATURE (°C)

I S H D N (μA )

100

-30

-5

161718192014-40

135DROPOUT VOLTAGE vs. LOAD CURRENT

I OUT (mA)

D R O P O U T V O L T A G

E (m V )

101

255075100

1251501752002252502753003250

0.1

100

DROPOUT VOLTAGE vs. LOAD CURRENT

I OUT (mA)

D R O P O U T V O L T A G

E (m V )

101

2550751001251501752002252502753000

0.1100

MAX5091

28V , 100mA, Low-Quiescent-Current LDO with Reset and Power-Fail Input/Output

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DROPOUT VOLTAGE vs. TEMPERATURE

TEMPERATURE (°C)

D R O P O U T V O L T A G

E (m V )

100

-5

501001502002503003504000-40

135

RESET THRESHOLD vs. TEMPERATURE

TEMPERATURE (°C)

R E S E T T H R E S H O L D V O L T A G E (V )

1006530-54.424.444.464.484.50

4.52

4.54

4.564.584.604.40

-40135RESET VOLTAGE vs. OUTPUT VOLTAGE

V OUT (V)

V R E S (V )

4.64.54.41234

4.3

4.7

SENSE THRESHOLD vs. TEMPERATURE

TEMPERATURE (°C)

S E N S E T H R E S H O L D (V )

100

-5

1.051.101.151.201.251.301.351.401.451.501.00

-40

135

SENSE OUTPUT vs. SENSE INPUT

SENSE INPUT (V)

S E N S E O U T P U T (V )

1.3

1.21.1

4501.0

1.4

POWER-SUPPLY REJECTION RATIO

vs. SUPPLY CURRENT

FREQUENCY (kHz)

P S R R (d B )

0.1

-70

-60-50-40-30-20

-100

-800.01

100

LOAD-TRANSIENT RESPONSE

200μs/div V OUT

5V AC-COUPLED 100mV/div

I OUT

20mA/div 50mA 100μA

C IN = 10μF

C OUT = 10μF/10m Ω ESR I STEP = 100μA TO 50mA

LINE-TRANSIENT RESPONSE

MAX5091 toc20

200μs/div

V OUT

5V AC-COUPLED 200mV/div I OUT = 1mA

V S

10V/div 40V 14V

Typical Operating Characteristics (continued)

(Typical Application Circuit , V S = +14V, C IN = 10μF, C OUT = 10μF, V SI = 0V, V EN = +2.4V, V OUT = +5V, T A = +25°C, unless other-wise noted.)

M A X 5091

28V , 100mA, Low-Quiescent-Current LDO with Reset and Power-Fail Input/Output

Typical Operating Characteristics (continued)

(Typical Application Circuit, V S = +14V, C IN = 10μF, C OUT = 10μF, V SI = 0V, V EN = +2.4V, V OUT = +5V, T A = +25°C, unless other-wise noted.)

V OUT STARTUP RESPONSE

MAX5091 toc21

10ms/div

V OUT 2V/div

V S 5V/div

I OUT = 10mA

ENABLE RESPONSE

200μs/div

OUT 0V

I OUT = 100mA

SHUTDOWN RESPONSE

200μs/div

V OUT 2V/div EN 2V/div 0V

I OUT = 100mA

MAX5091

28V , 100mA, Low-Quiescent-Current LDO with Reset and Power-Fail Input/Output

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Figure 1. Functional Diagram

M A X 5091

28V , 100mA, Low-Quiescent-Current LDO with Reset and Power-Fail Input/Output 10______________________________________________________________________________________

Detailed Description

Regulator

The MAX5091 high-voltage, LDO regulator operates from +5V to +28V input voltage. The device withstands up to 40V transients, providing protection against tem-porary overvoltage conditions like load dump. The MAX5091 incorporates internal feedback resistors for factory-preset voltages of either +5V (MAX5091A) or +3.3V (MAX5091B). The regulator is capable of driving up to 100mA of load current and features a typical cur-rent limit of 260mA. The regulator uses a pnp pass ele-ment and provides low 0.5V dropout while delivering 100mA load current. The output of the regulator follows closely to the input during turn-on. See the Output Voltage vs. Input Voltage graph in the Typical Operating Characteristics . This makes the usable input voltage range for 3.3V and 5V output down to 3.7V and 5.5V, respectively. The MAX5091 is designed to oper-ate with very low quiescent current during always-on operation when not in dropout. The regulator is stable with a wide variety of capacitors including low-ESR ceramic 10μF (0603 case size). The load-transient response curves depict the stability of the LDO when using different capacitance and ESR ranges. See the Capacitor S election and Regulator S tability section in the Applications Information .

Reset Output (RES )

The MAX5091 integrates a power-on-reset circuit. RES is an open-drain output that requires a pullup resistor to V OUT . The open-drain MOSFET can sink up to 825μA current while keeping the RES voltage below 0.4V. The internal reset circuit monitors the regulator output volt-age and RES asserts an active-low output when the regulator output falls below a reset threshold of typical-ly 0.9x V OUT . The RES output remains low when V OUT is below the reset threshold, and remains low for the duration of the reset timeout period (t RD ). The reset timeout period is programmable and can be set with an external capacitor connected from CT to ground. The duration of the delay as a function of CT is:

The default reset timeout period is 35μs when no capacitor is connected from CT to ground.

SI/SO Comparator

The MAX5091 includes an uncommitted comparator for monitoring the input voltage or for detecting power-fail conditions. The input SI is the noninverting input of the comparator. The open-drain output SO asserts low when voltage at the input SI drops below the threshold voltage, V ST (see Figure 1).The sense comparator typi-cally has a hysteresis of 100mV. Use the following equation to calculate the resistor-divider for program-ming the trip voltage (V TRIP ) during power-fail. See the Typical Application Circuit .

where V ST = 1.16V (typ). Choose R L between 100k Ωto 300k Ω.

Enable Input

The enable (EN) is a TTL-compatible logic input. Logic low at EN turns off the regulator and reduces the cur-rent consumption to 17μA (typ). It is internally pulled up to a logic-high voltage (3.6V max) by an internal resis-tor. Thus, the MAX5091 is enabled by default when V S is applied and EN is left unconnected. The regulator,reset supervisor circuit, and the sense comparator can be manually shut down by pulling EN low. For shut-down operation, the pulldown network must be capable of sinking 3μA max, since the internal pullup resistor sets the maximum pullup current at 3μA. The external pulldown device should not leak more than 1μA current when it is in the off-state.

Current Limit

The MAX5091 features a current limiter that monitors the output current and controls the pass transistor’s gate voltage, limiting the output current to typically 260mA. The output can be continuously shorted to ground without damaging the device at V S ≤16V. Note that the output short-circuit current may increase the power dissipation significantly and raise the junction temperature to its thermal-shutdown threshold. In such a case, the MAX5091 is temporarily turned off.

Thermal Shutdown

When the junction temperature exceeds T J = +165°C (typ), an internal thermal sensor signals the shutdown logic to turn off the pass transistor and allow the IC to cool. The thermal sensor turns the pass transistor on again after the IC’s junction temperature cools by +20°C (typ), resulting in a cycled output during contin-uous thermal-overload conditions. Thermal shutdown protects the MAX5091 in the event of fault conditions.For continuous operation, do not exceed the absolute maximum junction temperature of T J = +150°C.

MAX5091

28V , 100mA, Low-Quiescent-Current LDO with Reset and Power-Fail Input/Output

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Applications Information

Available Output Current Calculation

The MAX5091 high-voltage regulator provides up to 100mA of output current. The input voltage extends to +28V. Package power dissipation limits the amount of output current available for a given input/output voltage and ambient temperature. Figure 2 depicts the maxi-mum power dissipation curve for the 8-pin SO-EP pack-age. The graph assumes that the exposed metal back of the MAX5091 package is soldered to copper on a single layer PCB according to the JEDEC51 https://www.wendangku.net/doc/1813023119.html,e Figure 2 to determine the allowable package dissi-pation for a given ambient temperature. Alternately, use the following formula to calculate the allowable pack-age dissipation:

After determining the allowable package dissipation, cal-culate the maximum output current using the following

formula:

The above equations do not include the power dissipation from self-heating due to the IC ground current.

The junction-to-ambient thermal impedance depends on the area of the copper plane, its thickness, and the number of copper layers on PCB. For the higher power dissipation requirement, use multiple-layered PCBs with 2oz copper and a large copper area.

Capacitor Selection and

Regulator Stability

For stable operation over the full temperature range and with load currents up to 100mA, use a 10μF output capacitor with a low ESR. Table 1 shows a list of recom-mended output capacitor ESR for various load conditions.

P 1.538W For T 70C 1.5380.01923T C For 70C T 125C D A A A ()

=≤+°??+<≤+°?

?°°70Figure 2. 8-Pin SO-EP Maximum Power Dissipation vs.Temperature

Table 1. Recommended Output Capacitor ESR

M A X 5091

28V , 100mA, Low-Quiescent-Current LDO with Reset and Power-Fail Input/Output 12______________________________________________________________________________________

Chip Information

PROCESS: BiCMOS

Pin Configurations (continued)

MAX5091

28V , 100mA, Low-Quiescent-Current LDO with Reset and Power-Fail Input/Output

______________________________________________________________________________________13

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/1813023119.html,/packages .)

M A X 5091

28V , 100mA, Low-Quiescent-Current LDO with Reset and Power-Fail Input/Output 14______________________________________________________________________________________

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/1813023119.html,/packages .)

MAX5091

28V , 100mA, Low-Quiescent-Current LDO with Reset and Power-Fail Input/Output

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 ____________________15?2006 Maxim Integrated Products

is a registered trademark of Maxim Integrated Products, Inc.

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/1813023119.html,/packages .)