A8181 - Allegro MicroSystems, Inc.

8181

LOW-DROPOUT,

5 V REGULATOR

DISCONTINUED PRODUCT

— FOR REFERENCE ONLY

8181

LOW-DROPOUT, 5 V REGULATOR

— HIGH EFFICIENCY

Especially suited for hand-held, portable, battery-operated equip-

ment such as cellular telephones, the A8181SLB low dropout voltage

regulator provides high efficiency for maximum battery life in a mini-

mum package size. Equally applicable to camcorders and portable

computers, the device provides a fixed 5 V regulated continuous output

at almost 200 mA of load current under worst-case conditions. Under

normal operating conditions, output currents over 500 mA are

permitted.

A MOSFET pass element delivers high output current with an

input-output differential of less than 300 mV. For high efficiency, the

low dropout voltage allows a longer battery discharge before output

voltage regulation is lost. A low quiescent current, even during high

load conditions, makes the device ideal for standby power systems.

High regulator accuracy and excellent temperature characteristics are

provided by a bandgap reference. An enable input gives the designer

complete control over sequential power-up or emergency shutdown.

This device is supplied in a 16-lead wide-body, small-outline

plastic power package (SOIC) for surface-mount applications. The

copper batwing provides for maximum package power dissipation in

the smallest possible construction. The A8181SLB is rated for opera-

tion over a temperature range of -20°C to +85°C.

FEATURES AND BENEFITS

■High Efficiency Provides Extended Battery Life

■Less Than 300 mV Dropout Voltage

■Low Quiescent Current

■>200 mA Output Current

■LSTTL-Compatible ON/OFF Control

For Sequential Power-up or Emergency Shutdown

■Internal Thermal Protection

■SOIC Surface-Mount Package

Always order by complete part number: A8181SLB .

ABSOLUTE MAXIMUM RATINGS

at TA = +25°C

Input Voltage, VI................................... 10 V

Output Current, IO

(40% duty cycle)............................ 1 A*

(75% duty cycle)..................... 500 mA*

(continuous)............................ 370 mA*

Operating Temperature Range,

TA................................. -20°C to +85°C

Junction Temperature, TJ.............. +150°C†

Storage Temperature Range,

TS............................... -40°C to +150°C

* Output current rating is limited by input voltage,

duty cycle, and ambient temperature. Under any

set of conditions, do not exceed a junction

temperature of +150°C. See next page.

† Fault conditions that produce excessive

junction temperature will activate device thermal

shutdown circuitry. These conditions can be

tolerated but should be avoided.

Data Sheet

27468*

512

GROUND

Dwg. PS-018

710

GROUND GROUND

GROUND

OUT

ENABLE

NC NC

OUT

5 V

8181

LOW-DROPOUT,

5 V REGULATOR

115 Northeast Cutoff, Box 15036

Worcester, Massachusetts 01615-0036 (508) 853-5000

Maximum Allowable Output Current in Milliamperes with VI = 10 V, TJ = 150°C*

dc (Duty Cycle)

TA100% 90% 80% 70% 60% 50% 40% 30% 20%

25°C 370 415 465 530 620 745 930 1000 1000

50°C 295 330 370 425 495 595 745 995 1000

70°C 235 265 295 340 395 475 595 795 1000

85°C 190 215 240 275 320 385 485 645 970

= (TJ - TA)/([VI - VO] RθJA • dc) = (150 - TA)/(5 • 67 • dc)

Output current rating can be increased (to 1 A maximum) by heat sinking or reducing the input voltage. With an infinite heat sink, R-JA = R-JT =

6°C/W. Conditions that produce excessive junction temperature will activate device thermal shutdown circuitry. These conditions can be tolerated

but should be avoided.

FUNCTIONAL BLOCK DIAGRAM

12-13

Dwg. FS-012

BIAS DRIVE

ENABLE

THERMAL

PROTECT.

BANDGAP

REF.

ERROR

AMP

4-5

ENABLE

OUT

IN OUT

MAXIMUM ALLOWABLE OUTPUT CURRENT with device mounted on 2.24" x 2.24"

(56.9 mm x 56.9 mm) solder-coated copper-clad board in still air.

8181

LOW-DROPOUT,

5 V REGULATOR

ELECTRICAL CHARACTERISTICS at TA +25°C (unless otherwise noted).

Limits

Characteristic Symbol Test Conditions Min. Typ. Max. Units

Output Voltage VOTA = 25°C, 5.5 V ≤ VI ≤ 10 V, 4.90 5.00 5.10 V

0 mA ≤ IO ≤ 500 mA†

TA = 85°C, 5.5 V ≤ VI ≤ 10 V, 4.85 — 5.15 V

0 mA ≤ IO ≤ 500 mA*†

Output Volt. Temp. Coeff. αVO IO = 0 — ±100 — µV/°C

Line Regulation ∆VO(∆VI) 5.5 V ≤ VI ≤ 10 V, Output open — 10 30 mV

Load Regulation ∆VO(∆IO) 0 mA ≤ IO ≤ 500 mA†, VI = 6 V — 40 100 mV

Dropout Voltage VImin - VOIO = 500 mA† — — 300 mV

Quiescent Current IQVI = 10 V, IO = 500 mA† — 87 120 µA

VI = 10 V, Output open — 86 120 µA

IQ(off) VI = 10 V, Output open, VE = 0.4 V — — 20 µA

ENABLE Input Voltage VEH Output ON, VI = 10 V 2.4 — — V

VEL Output OFF, VI = 10 V — — 0.4 V

ENABLE Input Current IEVE = VI = 10 V — — ±0.1 µA

Thermal Shutdown Temp. TJ— 165 — °C

Thermal Resistance RθJA Mounted on 2.24" x 2.24" solder-coated — 67 — °C/W

copper-clad board in still air

RθJT — 6.0 — °C/W

Typical values are given for circuit design information only.

* This parameter is tested to a lot sample plan only.

† Pulse test (<20 ms).

(GND terminal current)

8181

LOW-DROPOUT,

5 V REGULATOR

115 Northeast Cutoff, Box 15036

Worcester, Massachusetts 01615-0036 (508) 853-5000

OUTPUT CURRENT, I

in mA

Dwg. GP-039-1

100 200 400 500300

T = 25°C

5.04

5.00

5.02

4.98

OUTPUT VOLTAGE, V

in VOLTS

4.96

4.94

5.06

4.92

V = 7 V

V = 6 V

V = 8 V

V = 10 V

V = 5.5 V

5.0

Dwg. GP-040-1

6.0 7.0 9.0 10

8.0

T = 25°C

5.04

5.00

5.02

4.98

OUTPUT VOLTAGE, V

in VOLTS

4.96

4.94

5.06

4.92

I = 0 mA

I = 500 mA

INPUT VOLTAGE, V

in VOLTS

100 mA INTERVALS

CAUTION: Maximum allowable duty cycle will be significantly less than 100% at high temperatures, at high input voltages, or at high output

currents. See Maximum Allowable Output Current table.

TYPICAL CHARACTERISTICS

5.0

Dwg. GP-040

6.0 7.0 9.0 10

8.0

T = -20°C

5.04

5.00

5.02

4.98

OUTPUT VOLTAGE, V

in VOLTS

4.96

4.94

5.06

4.92

I = 0 mA

INPUT VOLTAGE, V

in VOLTS

100 mA INTERVALS

I = 500 mA

OUTPUT CURRENT, I

in mA

Dwg. GP-039

100 200 400 500300

V = 7 V

V = 6 V

V = 8 V

V = 10 V

T = -20°C

5.04

5.00

5.02

4.98

OUTPUT VOLTAGE, V

in VOLTS

4.96

4.94

5.06

4.92

V = 5.5 V

LOAD REGULATION LINE REGULATION

8181

LOW-DROPOUT,

5 V REGULATOR

OUTPUT CURRENT, IO in mA

Dwg. GP-041

100 200 400 500300

T = -20°C

T = 25°C

T = 85°C

0.3

0.4

0.2

DROPOUT VOLTAGE in VOLTS

0.1

0.5

DROPOUT VOLTAGE OUTPUT VOLTAGE vs TEMP.

CAUTION: Maximum allowable duty cycle will be significantly less than 100% at high temperatures, at high input voltages, or at high output

currents. See Maximum Allowable Output Current table.

TYPICAL CHARACTERISTICS (cont’d)

5.0

Dwg. GP-040-2

6.0 7.0 9.0 10

8.0

T = 85°C

5.04

5.00

5.02

4.98

OUTPUT VOLTAGE, V

in VOLTS

4.96

4.94

5.06

4.92

I = 0 mA

I = 500 mA

INPUT VOLTAGE, V

in VOLTS

100 mA INTERVALS

OUTPUT CURRENT, I

in mA

Dwg. GP-039-2

100 200 400 500300

T = 85°C

5.04

5.00

5.02

4.98

OUTPUT VOLTAGE, V

in VOLTS

4.96

4.94

5.06

4.92

V = 7 V

V = 6 V

V = 8 V

V = 10 V

V = 5.5 V

LOAD REGULATION LINE REGULATION

-50

AMBIENT TEMPERATURE, T

in °C

Dwg. GP-036

5.01

4.99

0 +50

5.00

+100

4.98

OUTPUT VOLTAGE, V

in VOLTS

V = 6 V

I = 0 mA

8181

LOW-DROPOUT,

5 V REGULATOR

115 Northeast Cutoff, Box 15036

Worcester, Massachusetts 01615-0036 (508) 853-5000

4.0

Dwg. GP-042

6.0 7.0 9.0 10

8.0

INPUT VOLTAGE, VI in VOLTS

QUIESCENT (GROUND TERMINAL) CURRENT in µA

5.03.0

T = 25°C

I = 0 mA

TRANSIENT PERFORMANCE

Dwg. WP-018

500 mA

20 mA

5.5 V

5.0 V

4.5 V <100 µs<500 µs

VI = 5.5 V to 10 V, TA = -20°C to +85°C, CO = 4.7 µF

CAUTION: Maximum allowable duty cycle will be significantly less than 100% at high temperatures, at high input voltages, or at high output

currents. See Maximum Allowable Output Current table.

TYPICAL CHARACTERISTICS (cont’d)

OUTPUT CURRENT, I

in mA

Dwg. GP-038

100 200 400 500

300

QUIESCENT (GROUND TERMINAL) CURRENT in µA

V = 7 V

V = 6 V

V = 8 V

V = 9 V

V = 10 V

T = 25°C

-50

AMBIENT TEMPERATURE, T

in °C

Dwg. GP-037

0 +50

+100

V = 6 V

I = 0 mA

QUIESCENT (GROUND TERMINAL) CURRENT in µA

QUIESCENT (GROUND TERMINAL) CURRENT

8181

LOW-DROPOUT,

5 V REGULATOR

Dimensions in Inches

(Based on 1 mm = 0.3937”)

NOTES: 1. Webbed lead frames. Leads 4, 5, 12, and 13 are internally one piece.

2. Lead spring tolerance is non-cumulative.

3. Exact body and lead configuration at vendor’s option within limits shown.

Dimensions in Millimeters

0° TO 8°

1 2 3

0.2992

0.2914

0.4133

0.3977

0.419

0.394

0.020

0.013

0.0926

0.1043

0.0040 MIN.

0.0125

0.0091

0.050

0.016

Dwg. MA-008-17A in

0.050

BSC

16 9

0°

8°

7.60

7.40

10.50

10.10

10.65

10.00

0.51

0.33

2.65

2.35

0.10

MIN.

0.32

0.23

1.27

0.40

Dwg. MA-008-17A mm

1.27

BSC

8181

LOW-DROPOUT,

5 V REGULATOR

115 Northeast Cutoff, Box 15036

Worcester, Massachusetts 01615-0036 (508) 853-5000

Allegro MicroSystems, Inc. reserves the right to make, from time to time, such departures from

the detail specifications as may be required to permit improvements in the design of its products.

Components made under military approvals will be in accordance with the approval requirements.

The information included herein is believed to be accurate and reliable. However, Allegro

MicroSystems, Inc. assumes no responsibility for its use; nor for any infringements of patents or other

rights of third parties which may result from its use.