National Semiconductor LM384 Technical data

LM384
5W Audio Power Amplifier

LM384 5W Audio Power Amplifier

August 2000

General Description

The LM384 is a power audio amplifier for consumer applica­tions. In order to hold system cost to a minimum, gain is
internally fixed at 34 dB. A unique input stage allows ground
referenced input signals. The output automatically self­centers to one-half the supply voltage.

The output is short-circuit proof with internal thermal limiting.
The package outline is standard dual-in-line. A copper lead
frame is used with the center three pins on either side
comprising a heat sink. This makes the device easy to use in
standard p-c layout.

Uses include simple phonograph amplifiers, intercoms, line
drivers, teaching machine outputs, alarms, ultrasonic driv­ers, TV sound systems, AM-FM radio, sound projector sys­tems, etc. See AN-69 for circuit details.

Schematic Diagram

Features

n Wide supply voltage range: 12V to 26V
n Low quiescent power drain
n Voltage gain fixed at 50
n High peak current capability: 1.3A
n Input referenced to GND
n High input impedance: 150kΩ
n Low distortion: 0.25% (P
n Quiescent output voltage is at one half of the supply

voltage

n Standard dual-in-line package

=4W, RL=8Ω)

O

00784303

© 2004 National Semiconductor Corporation DS007843 www.national.com

Absolute Maximum Ratings (Note 1)

LM384

If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.

Supply Voltage 28V

Peak Current 1.3A

Power Dissipation (See (Notes 4, 5)) 1.67W

Input Voltage

Storage Temperature −65˚C to +150˚C

±

0.5V

Operating Temperature 0˚C to +70˚C

Lead Temperature

(Soldering, 10 sec.) 260˚C

Thermal Resistance

θ

JC

θ

JA

Note 1: Absolute Maximum Ratings indicate limits beyond which damage to
the device may occur. Operating Ratings indicate conditions for which the
device is functional, but do not guarantee specific performance limits.

Electrical Characteristics (Note 2)

Symbol Parameter Conditions Min Typ Max Units

Z

IN

I

BIAS

A

V

P

OUT

I

Q

V

OUT Q

BW Bandwidth P

+

V

I

SC

PSRR

RTO

THD Total Harmonic Distortion P

Note 2: V+= 22V and TA= 25˚C operating with a Staver V7 heat sink for 30 seconds.

Note 3: Rejection ratio referred to the output with C

Note 4: The maximum junction temperature of the LM384 is 150˚C.

Note 5: The package is to be derated at 15˚C/W junction to heat sink pins.

Note 6: Output is fully protected against a shorted speaker condition at all voltages up to 22V.

Input Resistance 150 kΩ

Bias Current Inputs Floating 100 nA

Gain 40 50 60 V/V

Output Power THD = 10%, RL=8Ω 5 5.5 W

Quiescent Supply Current 8.5 25 mA

Quiescent Output Voltage 11 V

= 2W, RL=8Ω 450 kHz

OUT

Supply Voltage 12 26 V

Short Circuit Current (Note 6) 1.3 A

Power Supply Rejection Ratio 31 dB

(Note 3) )

= 4W, RL=8Ω 0.25 1.0 %

OUT

= 5 µF, freq = 120 Hz.

BYPASS

30˚C/W

79˚C/W

Heat Sink Dimensions

Staver Company

41 Saxon Ave.

P.O. Drawer H

Bay Shore, N.Y.

Tel: [phone]

Staver “V7” Heat Sink

00784304

www.national.com 2

Typical Performance Characteristics

LM384

Device Dissipation vs
Ambient Temperature

Supply Decoupling vs

Frequency

00784310

Thermal Resistance vs

Square Inches

00784311

Total Harmonic Distortion

vs Output Power

Output Voltage Gain vs

Frequency

00784312

00784314

00784313

Total Harmonic Distortion

vs Frequency

00784315

www.national.com3

Typical Performance Characteristics (Continued)

LM384

Power Supply Current vs

Supply Voltage

Device Dissipation vs

Output Power — 16Ω Load

00784316

Device Dissipation vs

Output Power — 8Ω Load

00784318

Block and Connection Diagrams

00784317

Device Dissipation vs

Output Power — 4Ω Load

00784319

Dual-In-Line Package

00784301

www.national.com 4

Note 7: Heatsink Pins

00784302

Top View Order Number LM384NSee NS Package

Number N14A

Typical Applications

LM384

Typical 5W Amplifier

00784306

Bridge Amplifier

*For stability with high current loads

00784307

Intercom

00784308

www.national.com5

Typical Applications (Continued)

LM384

Phase Shift Oscillator

00784309

www.national.com 6

Physical Dimensions inches (millimeters) unless otherwise noted

Molded Dual-In-Line Package (N)

Order Number LM384N

NS Package Number N14A

LM384 5W Audio Power Amplifier

National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves
the right at any time without notice to change said circuitry and specifications.

For the most current product information visit us at www.national.com.

LIFE SUPPORT POLICY

NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS
WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL COUNSEL OF NATIONAL SEMICONDUCTOR
CORPORATION. As used herein:

1. Life support devices or systems are devices or systems
which, (a) are intended for surgical implant into the body, or
(b) support or sustain life, and whose failure to perform when
properly used in accordance with instructions for use

2. A critical component is any component of a life support
device or system whose failure to perform can be reasonably
expected to cause the failure of the life support device or
system, or to affect its safety or effectiveness.

provided in the labeling, can be reasonably expected to result
in a significant injury to the user.

BANNED SUBSTANCE COMPLIANCE

National Semiconductor certifies that the products and packing materials meet the provisions of the Customer Products Stewardship
Specification (CSP-9-111C2) and the Banned Substances and Materials of Interest Specification (CSP-9-111S2) and contain no ‘‘Banned
Substances’’ as defined in CSP-9-111S2.

National Semiconductor
Americas Customer
Support Center

Email: [e-mail]
Tel: [phone]

www.national.com

National Semiconductor
Europe Customer Support Center

Fax: [phone]

Email: [e-mail]
Deutsch Tel: [phone]
English Tel: [phone]
Français Tel: [phone]

National Semiconductor
Asia Pacific Customer
Support Center

Email: [e-mail]

National Semiconductor
Japan Customer Support Center

Fax: [phone]
Email: [e-mail]
Tel: [phone]