NSC LM4753T Datasheet

LM4753
Dual 10W Audio Power Amplifier w/Mute, Standby and
Volume Control

General Description

The LM4753 is a stereo audio amplifier capable of delivering
10W/channel at 10%distortion into a 8Ω load. The power
amp has an internally set gain of 30 dB. A 0V–5V DC con­trolled volume block provides80dBofattenuationfrom input
to line-out. Line outputs are available after the volume con­trol for signal routing.

The amplifier has a smooth transition fade-in/out mute and a
power conserving standby function which are controlled
through TTL or CMOS logic. Both functions provide over
75 dB of attenuation.

The LM4753 maintains an excellent Signal-to-Noise ratio of
greater than 70 dB with a low noise floor less than 2 mV.The
IC also maintains above 50 dB of channel separation.

The LM4753 is available in a 15-lead non-isolated plastic
package and is designed for use in TV applications requiring
single supply operation.

Key Specifications

n Output power into 8Ω at 10%THD 10W
n Maximum operating voltage 28V
n Power output stage Noise floor 2 mV
n Line output Noise floor 55 µV
n 0V–5V DC controlled volume attenuation 80 dB
n Mute attenuation 75 dB
n Standby-mode supply current 7 mA

Features

n Quiet fade-in/out mute function
n Stereo variable line-out pins
n AC output short circuit protection
n Thermal shutdown protection

Applications

n Stereo TVs
n Component stereo
n Compact stereo

Typical Application

DS100043-1

FIGURE 1. Typical Audio Amplifier Application Circuit

June 1999

LM4753 Dual 10W Audio Power Amplifier w/Mute, Standby and Volume Control

© 1999 National Semiconductor Corporation DS100043 www.national.com

Connection Diagram

Plastic Package

DS100043-2

Top View

Order Number

See NS Package Number TA15A for

Staggered Lead Non-Isolated Package

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Absolute Maximum Ratings (Notes 3, 4)

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

Supply Voltage 32V
Output Current Internally Limited
Power Dissipation (Note 5) 22W
ESD Susceptibility (Note 6) 2000V
ESD Susceptibility (Note 7) 250V
Junction Temperature 150˚C

Soldering Information
T Package (10 sec) 260˚C
Storage Temperature −40˚C to +150˚C
Input Signal Voltage Range

±

3V

Operating Ratings (Notes 3, 4)

Temperature Range
T

MIN

≤ TA≤ T

MAX

−40˚C ≤ TA≤ +85˚C

Supply Voltage 15V to 28V

θ

JA

(Junction to Ambient) 35˚C/W

θ

JC

(Junction to Case) 1.5˚C/W

Electrical Characteristics (Notes 3, 4)

The following specifications apply for VCC= +22V, and Volume@0 dB unless otherwise specified. Limits apply for TA= 25˚C.

Symbol Parameter Conditions

LM4753

Units

(Limits)

Typical

(Note 8)

Limit

(Note 9)

I

CQ

(Note 1)

Total Quiescent Power Supply
Current

V

CM

= 0V, Vo= 0V, Io= 0 mA 20 mA (min)

80 140 mA (max)

I

STBY

(Note 1)

Standby Current V

STDBY

= 5V, Standby-on 7 10 mA (max)

I

MUTE

Mute Current V

MUTE

= 5V Mute-on 13 20 mA

A

M

(Note 2)

Mute Attenuation V

MUTE

= 5V, V

STDBY

= 0V. Mute-on

Signal Input

75 60 dB (min)

V

MUTE

= 0V. V

STDBY

= 0V. Mute-off

2 Vrms

±

5dB

Volume Attenuation Range 80 70 dB (min)
Volume Absolute Attenuation

Line-out

Pin 3

@

0V=80 dB, 2V=14 dB,

3V=8 dB, 4V=3 dB, 5V=0dB

±

3

±

5 dB (max)

Line-out Offset Voltage 20 40 mV (max)

P

O

(Note 1)

Output Power (Continuous Average) THD+N = 10%(max)

f = 1 kHz, R

L

=8Ω,VCC= 28 11.8 W

f = 1 kHz, R

L

=8Ω,VCC= 22V 7 6.5 W(min)

THD+N
(Note 2)

Total Harmonic Distortion Plus Noise P

o

=1W,f=1kHz, RL=8Ω 0.4 1

%

(max)

Xtalk
(Note 2)

Channel Separation f = 1 kHz, P

o

= 5W, RL=8Ω 50 dB

Power Amp Closed-Loop Gain Error Internal Gain = 30 dB 0.5

±

1 dB (max)

SR
(Note 2)

Slew Rate V

IN

= 100 mVp-p, t

RISE

= 2 ns, RL=8Ω 3 V/µs

R

IN

(Note 1)

Input Impedance 32 kΩ

I

O

(Note 1)

Output Current Limit V

IN

= 100 mV DC, tON= 1 ms, RL=1Ω 2.5 2.0 A(min)

PSRR
(Note 2)

Power Supply Rejection Ratio Vpin 13 AC = 1 Vrms, f = 100 Hz 50 dB

V

CM

= 0V, Io=0mA

GBWP Gain-Bandwidth Product f

o

= 100 kHz, VIN= 50 mvrms 2 MHz

Power Bandwidth −3 dB Bandwidth at 5W 90 kHz

eVCA

out

VCA Output Noise IHF - A Weighting Filter

R

IN

=25Ω

55 µV

e

out

Power Amp Output Noise IHF - A Weighting Filter

R

IN

=25Ω

1.8 mV

SNR Signal-to-Noise Ratio Measured at 1 kHz, R

s

=25Ω

P

o

= 4.8W, A - Weighted, 70 dB

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Electrical Characteristics (Notes 3, 4) (Continued)

The following specifications apply for VCC= +22V, and Volume@0 dB unless otherwise specified. Limits apply for TA= 25˚C.

Symbol Parameter Conditions

LM4753

Units

(Limits)

Typical

(Note 8)

Limit

(Note 9)
Standby
V

IL

Standby Low Input Voltage 0.8 V (max)

V

IH

Standby High Input Voltage 2.0 V (min)
Mute
V

IL

Mute Low Input Voltage 0.8 V (max)
V

IH

Mute High Input Voltage 2.0 V (min)

Note 1: DC Electrical Test.
Note 2: AC Electrical Test.
Note 3: 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 state DC and AC electrical specifications under particular test conditions
which guarantee specific performance limits. This assumes that the device is within the Operating Ratings. Specifications are not guaranteed for parameters where
no limit is given, however, the typical value is a good indication of device performance.

Note 4: All voltages are measured with respect to the ground (pin 8), unless otherwise specified.
Note 5: The maximum power dissipation must be derated at elevated temperatures and is dictated by T

JMAX

, θJA, and the ambient temperature, TA. The maximum

allowable power dissipation is PDMAX = (T

JMAX-TA

)/θJAor the number given in the Absolute Maximum Ratings, whichever is lower. For operating at case tempera-

tures above 25˚C, the device must be derated based on a 150˚C maximum junction temperature and a thermal resistance of θ

JC

= 5˚C/W (junction to case).

Note 6: Human body model, 100 pF discharged through a 1.5 kΩ resistor.
Note 7: Machine model, 200 pF–240 pF discharge through all pins.
Note 8: Typicals are measured at 25˚C and represent the parametric norm.
Note 9: Limits are guarantees that all parts are tested in production to meet the stated values.

Standby Mute Pin Function Table

Standby (Pin 9) Mute (Pin 10) Operating Condition

“L” or Open “L” Play
“L” or Open “H” or Open Mute

“H” “L” Standby
“H” “H” or Open Standby

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