Allegro A8184SLT Datasheet

VR

2

3 V

31

27468.6A

8184

LOW-DROPOUT, 3 V REGULATOR

— HIGH EFFICIENCY

Designed specifically to meet the requirement for extended opera­tion of battery-powered equipment such as cordless and cellular
telephones, the A8184SLT voltage regulator offers the reduced dropout
voltage and quiescent current essential for maximum battery life.
Applicable also to palmtop computers and personal data assistants, the
device delivers a regulated, continuous 3 V output at up to 75 mA under
normal operating conditions, or to 150 mA (transient) under worst-case
conditions.

A PMOS pass element provides a typical dropout voltage of only
90 mV at 60 mA of load current. The low dropout voltage permits
deeper battery discharge before output regulation is lost. Furthermore,
quiescent current does not increase as the dropout voltage is ap­proached, an ideal feature in standby/resume power systems where
data integrity is crucial. Regulator accuracy and excellent temperature
characteristics are provided by a bandgap reference.

Data Sheet

IN

GND

OUT

Dwg. PS-022

This device is supplied in a small-outline plastic transistor package
(SOT-89/TO-243AA) for surface-mount applications. The A8184SLT is
rated for operation over a temperature range of -20°C to +85°C. A
similar device with an ENABLE input for control over sequential power
up, standby, or power down is the A8183SLU.

FEATURES AND BENEFITS

■ High Efficiency Provides Extended Battery Life

ABSOLUTE MAXIMUM RATINGS

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

Output Current, IO. . . . . . . . . 150 mA*

Operating Temperature Range,

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

DISCONTINUED PRODUCT

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.

— FOR REFERENCE ONLY

†

■ 90 mV Typical Dropout Voltage at IO = 60 mA

■ 45 µA Typical Quiescent Current at VI = 6 V

■ Up to 150 mA Output Current

■ Internal Thermal Protection

■ Surface-Mount Package

APPLICATIONS

■ Cordless and Cellular Telephones

■ Personal Data Assistants

■ Personal Communicators

■ Palmtop Computers

Always order by complete part number: A8184SLT .

8184

LOW-DROPOUT,
3 V REGULATOR

FUNCTIONAL BLOCK DIAGRAM

IN

GND

1

BIAS

DRIVE

ERROR

3

OUT

AMP

BANDGAP

THERMAL

PROTECT.

2

REF.

TAB

Dwg. FS-012-4

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.

Maximum Allowable Output Current in Milliamperes with VI = 8 V, TJ = 150°C, Period ≤10 s*

dc (Duty Cycle)

T

A

25°C 95 105 120 135 150 150 150 150 150

50°C 75 85 95 110 125 150 150 150 150

70°C 60 65 75 85 100 120 150 150 150

85°C 50 55 60 70 80 100 125 150 150

*IO = (TJ - TA)/([VI - VO] R

Output current rating can be increased (to 150 mA maximum) by heat sinking or reducing the input voltage. Conditions that produce excessive
junction temperature will activate device thermal shutdown circuitry. These conditions can be tolerated but should be avoided.

100% 90% 80% 70% 60% 50% 40% 30% 20%

• dc) = (150 - TA)/(5 • 258 • dc)

θJA

115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 [phone]
Copyright © 1994, 2000, Allegro MicroSystems, Inc.

8184

LOW-DROPOUT,

3 V REGULATOR

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

Limits

Characteristic Symbol Test Conditions Min. Typ. Max. Units

Output Voltage V

Output Volt. Temp. Coeff. α

Line Regulation ∆V

Load Regulation ∆V

O

VO

O(∆VI)

O(∆IO)

4 V ≤ VI ≤ 8 V, TA = +25°C 2.95 3.00 3.05 V

10 µA ≤ I

= 3 V, IO = 60 mA*, -20°C ≤ TA ≤ +85°C 2.70 — — V

V

I

≤ 100 mA* -20°C ≤ TA ≤ +85°C 2.90 3.00 3.10 V

O

VI = 6 V, IO = 10 mA — — ±1.0 mV/°C

6 V ≤ VI ≤ 8 V, IO = 1 mA — 4.0 10 mV

4 V ≤ V

≤ 6 V, IO = 1 mA — 9.5 18 mV

I

1 mA ≤ IO ≤ 100 mA*, VI = 8 V — 19 30 mV

1 mA ≤ I

1 mA ≤ I

≤ 100 mA*, VI = 6 V — 14 25 mV

O

≤ 100 mA*, VI = 4 V — 8.0 20 mV

O

Dropout Voltage VImin - VOIO = 60 mA* — 90 150 mV

= 125 mA* — 190 300 mV

I

O

Quiescent Current I

Q

VI = 6 V, 1 mA ≤ IO ≤ 100 mA*, VE ≥ 2.0 V — 45 60 µA

(GND terminal current) VI = 8 V, 1 mA ≤ IO ≤ 100 mA*, VE ≥ 2.0 V — 50 65 µA

Thermal Shutdown Temp. T

Thermal Resistance R

θJA

J

Mounted on 2.24" x 2.24" solder-coated — 258 — °C/W

150 — — °C

copper-clad board in still air

Typical values are at TA = +25°C and are given for circuit design information only.

* Pulse test (≤20 ms). See previous page for duty cycle limitations.