NSC LM4854MTX, LM4854MT, LM4854LD, LM4854IBLX, LM4854IBL Datasheet

LM4854

1.9W Monaural, 85mW Stereo Headphone Audio
Amplifier

General Description

The unity-gain stable LM4854 is both a mono differential
output (for bridge-tied loads, or BTL) audio power amplifier
and a single-ended (SE) stereo headphone amplifier. Oper­ating on a single 5V supply, the mono BTL mode delivers

1.1W (typ) to an 8Ω load, 1.7W (typ) to a 4Ω load (Note 1) at
1% THD+N. In SE stereo mode, the amplifier will deliver
85mW to 32Ω loads. The LM4854 features a new circuit
topology that suppresses output transients (’click and pops’)
and eliminates SE-mode output coupling capacitors, saving
both component and board space costs. The LM4854 has
three inputs: one pair for a two-channel stereo signal and the
third for a single-channel mono input.

The LM4854 is designed for PDA, cellular telephone, note­book, and other handheld portable applications. It delivers
high quality output power from a surface-mount package and
requires few external components. Other features include an
active-low micropower shutdown mode, an "instant-on" low
power standby mode, and thermal shutdown protection.

The LM4854 is available in the very space-efficient 12-lead
micro SMD, exposed-DAP LLP for higher power applica­tions, and TSSOP packages.

Note 1: An LM4854LD that has been properly mounted to a circuit board will
deliver 1.7W (typ) into a 4Ω load.

Key Specifications

j

LLP BTL output power (RL= 3.2Ω and

THD+N = 1%)

VDD= 3.0V 1.0W (typ)

V

DD

= 5.0V 1.9W (typ)

j

LLP BTL output power (RL=4Ω and

THD+N = 1%)

VDD= 3.0V 900mW (typ)

V

DD

= 5.0V 1.7W (typ)

j

LLP BTL output power (RL=8Ω and

THD+N = 1%)

VDD= 3.0V 380mW (typ)

V

DD

= 5.0V 1.1W (typ)

j

SE output power (RL=32Ω and THD+N

= 1.0%)

V

DD

= 3.0V 32mW (typ)

V

DD

= 5.0V 93mW (typ)

j

Micropower shutdown supply current

V

DD

= 3.0V 0.005µA (typ)

V

DD

= 5.0V 0.05µA (typ)

j

Standby supply current

V

DD

= 3.0V 16µA (typ)

V

DD

= 5.0V 27µA (typ)

j

PSRR (f = 1kHz, 3.0V ≤ VDD≤ 5.0V,

(Fig. 1))

BTL 60dB (typ)

SE 66dB (typ)

Features

n Fast 0.1ms (typ) and 1.0ms (max) turn-on and turn-off

time

n Eliminates SE amplifier output coupling capacitors
n Advanced "click and pop" suppression circuitry
n Stereo headphone amplifier mode
n Low-power standby and ultra-low current micropower

shutdown modes

n Thermal shutdown protection circuitry
n 2.4V to 5.5V operation
n Unity-gain stable
n Gain set with external resistors
n Space-saving micro SMD package, exposed-DAP LLP,

and TSSOP

Applications

n PDAs
n Notebook computers
n Cellular phones
n Handheld portable electronic devices

Boomer®is a registered trademark of National Semiconductor Corporation.

April 2003

LM4854 1.9W Monaural, 85mW Stereo Headphone Audio Amplifier

© 2003 National Semiconductor Corporation DS200382 www.national.com

Typical Application

(Pin out shown for the 12-pin large bump micro SMD IBL package. Consult the "Connection Diagrams" for the LLP or MT
package pin out.)

20038201

FIGURE 1. Typical Audio Amplifier Application Circuit

LM4854

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Connection Diagrams

20038202

Top View (Bump-side down)

Order Number LM4854IBL

See NS Package Number BLA12BAB

Micro SMD Marking

20038203

Top View

X - Date Code
T - Die Traceability
G - Boomer Family

54 - LM4854IBL

LM4854IBL Pin Designation

Pin (Bump) Number Pin Function

A1 L-IN

B1 GND

C1 R-IN

D1 MONO-IN

A2 L-OUT

B2 BYPASS

C2 HP-SENSE

D2 R-OUT

A3 SHUTDOWN

B3 V

DD

C3 BTL-OUT

D3 STANDBY

LM4854

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Connection Diagrams

20038204

Top View

Order Number LM4854LD

See NS Package Number LDA14A

200382A5

Top View

U - Fab Code

Z - Plant Code

XY - Date Code

TT - Die Tracebility

Bottom Line - Part Number

20038205

Top View

Order Number LM4854MT

See NS Package Number MTC14

200382A6

Top View

Z - Plant Code

XY - Date Code

TT - Die Traceability

Bottom 2 lines - Part Number

LM4854

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Absolute Maximum Ratings (Notes 2,

3)

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

Supply Voltage 6.0V

Storage Temperature −65˚C to +150˚C

Input Voltage −0.3V to V

DD

+ 0.3V

Power Dissipation(Note 4) Internally Limited

ESD Susceptibility (Note 5)

All pins except Pin C3 (IBL), Pin11

(LD/MT) 2000V

Pin C3 (IBL), Pin 11 (LD/MT) 8000V

ESD Susceptibility(Note 6) 200V

Junction Temperature (T

J

) 150˚C

Solder Information

Small Outline Package

Vapor Phase (60 sec.) 215˚C

Infrared (15 sec.) 220˚C

See AN-540 "Surface Mounting and
their Effects on Product Reliability"
for other methods of soldering
surface-mount devices.

Thermal Resistance

θ

JA

(typ) — BLA12BAB 121˚C/W

θ

JC

(typ) — LDA14A 3˚C/W

θ

JA

(typ) — LDA14A 42˚C/W (Note 7)

θ

JC

(typ) — MTC14 40˚C/W

θ

JA

(typ) — MTC14 109˚C/W

Operating Ratings (Note 3)

Temperature Range

T

MIN

≤ TA≤ T

MAX

−40˚C ≤ TA≤ +85˚C

Supply Voltage 2.4V ≤ V

DD

≤ 5.5V

Electrical Characteristics for Entire Amplifier (VDD= 5V)

The following specifications apply for circuit shown in Figure 1, unless otherwise specified. Limits apply for TA= 25˚C.

Symbol Parameter Conditions LM4854 Units

(Limits)

Typical

(Note 8)

Limit

(Notes 9,

10)

I

DD

Quiescent Power Supply Current VIN= 0V; IO= 0A, No Load 5.0 12 mA max)

V

IN

= 0V; IO= 0A, 8Ω Load 6.5 15 mA (max)

I

STBY

Standby Quiescent Power Supply
Current

V

STANDBY

= GND 27 35 µA (max)

I

SD

Shutdown Quiescent Power
Supply Current

V

SHUTDOWN

= GND 0.05 0.2 µA (max)

V

OS

Output Offset Voltage 8Ω Load 2.0 40 mV (max)

PSRR Power Supply Rejection Ratio C

BYPASS

= 1.0µF, R

SOURCE

=10Ω

V

RIPPLE

= 200mV

p-p

sinewave

BTL, R

L

=8Ω,RIN=10Ω

f

IN

= 217Hz

f

IN

= 1kHz

SE, R

L

=32Ω,RIN=10Ω

f

IN

= 217Hz

f

IN

= 1kHz

61
63

dB
dB

68
71

dB
dB

t

RSH

Return-from-Shutdown Time C

BYPASS

= 1.0µF 200 ms

t

RST

Return-from-Standby Time 0.1 1.0 ms(max)

V

IH

Shutdown or Standby Logic High
Treshold

1.4 V (min)

V

IL

Shutdown or Standby Logic Low
Treshold

0.4 V (max)

LM4854

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Electrical Characteristics Bridged-Mode Operation (VDD= 5V)

The following specifications apply for for the circuit shown in Figure 1 and a measurement bandwith of 20Hz to 80kHz, unless
otherwise specified. Limits apply for T

A

= 25˚C.

Symbol Parameter Conditions LM4854 Units

(Limits)

Typical

(Note 8)

Limit

(Notes 9,

10)

P

O

Output Power (Note 11) THD = 1% (max); f = 1kHz (Note12)

R

L

= 3.2Ω (LM4854LD)

R

L

=4Ω (LM4854LD)

R

L

=8Ω

1.9

1.7

1.1 1.0

W
W

W (min)

THD = 10% (max); f = 1kHz (Note12)

R

L

= 3.2Ω (LM4854LD)

R

L

=4Ω (LM4854LD)

R

L

=8Ω

2.3

2.1

1.3

W
W
W

THD+N Total Harmonic Distortion+Noise 20Hz ≤ f

IN

≤ 20kHz

R

L

=4Ω,PO= 1.0W (LM4854LD)

R

L

=8Ω,PO= 400mW

0.3

0.18

%
%

f

IN

= 1kHz

R

L

=4Ω,PO= 1.5W (LM4854LD)

R

L

=8Ω,PO= 50mW

0.1

0.08

%
%

S/N Signal-to-Noise Ratio f

IN

= 1kHz, C

BYPASS

= 1.0µF

P

O

= 900mW, RL=8Ω 90 dB

Electrical Characteristics : SE Operation (VDD= 5V)

The following specifications apply for for the circuit shown in Figure 1 and a measurement bandwith of 20Hz to 80kHz, unless
otherwise specified. Limits apply for T

A

= 25˚C.

Symbol Parameter Conditions LM4854 Units

(Limits)

Typical

(Note 8)

Limit

(Notes 9,

10)

P

O

Output Power (Note 11) THD+N = 1.0%, f = 1kHz, RL=32Ω

THD+N = 10%, f = 1kHz, R

L

=32Ω

THD+N = 1.0%, f = 1kHz, R

L

=16Ω

THD+N = 10%, f = 1kHz, R

L

=16Ω

93
105
170
200

85

140

mW(min)

mW

mW(min)

mW

THD+N Total Harmonic Distortion+Noise 20Hz ≤ f

IN

≤ 20kHz

R

L

=32Ω,PO= 50mW 0.3 %

VOUT Output Voltage Swing THD = 1.0%, R

L

=5kΩ 4.0 V

P-P

XTALK Channel Separation fIN= 1kHz, C

BYPASS

= 1.0µF, RL=32Ω 55 dB

S/N Signal-to-Noise Ratio f

IN

= 1kHz, C

BYPASS

= 1.0µF

P

O

= 50mW, RL=32Ω 90 dB

Electrical Characteristics for Entire Amplifier (VDD= 3.0V)

The following specifications apply for circuit shown in Figure 1, unless otherwise specified. Limits apply for TA= 25˚C.

Symbol Parameter Conditions LM4854 Units

(Limits)

Typical

(Note 8)

Limit

(Notes 9,

10)

I

DD

Quiescent Power Supply Current VIN= 0V, IO= 0A, 8Ω Load 4.0 10 mA (max)

I

STBY

Standby Quiescent Power Supply
Current

V

STANDBY

= GND 16.0 20.0 µA (max)

I

SD

Shutdown Current V

SHUTDOWN

= GND 0.005 0.02 µA (max)

V

OS

Output Offset Voltage 8 Ω Load 2.0 40 mV (max)

LM4854

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Electrical Characteristics for Entire Amplifier (VDD= 3.0V) (Continued)

The following specifications apply for circuit shown in Figure 1, unless otherwise specified. Limits apply for TA= 25˚C.

Symbol Parameter Conditions LM4854 Units

(Limits)

Typical

(Note 8)

Limit

(Notes 9,

10)

PSRR Power Supply Rejection Ratio C

BYPASS

= 1.0µF, R

SOURCE

=10Ω

V

RIPPLE

= 200mV

p-p

sinewave

BTL, R

L

=8Ω,RIN=10Ω

f

IN

= 217Hz

f

IN

= 1kHz

SE, R

L

=32Ω,RIN=10Ω

f

IN

= 217Hz

f

IN

= 1kHz

62
62

dB
dB

68
72

dB
dB

t

RSH

Return-from-Shutdown Time C

BYPASS

= 1.0µF 200 ms

t

RST

Return-from-Standby Time 0.1 1.0 ms(max)

V

IH

Shutdown or Standby Logic High
Treshold

1.4 V (min)

V

IL

Shutdown or Standby Logic Low
Treshold

0.4 V (max)

Electrical Characteristics : Bridged-Mode Operation (VDD= 3.0V) (Notes 4, 9)

The following specifications apply for for the circuit shown in Figure 1 and a measurement bandwith of 20Hz to 80kHz, unless
otherwise specified. Limits apply for T

A

= 25˚C.

Symbol Parameter Conditions LM4854 Units

(Limits)

Typical

(Note 8)

Limit

(Notes 9,

10)

P

O

Output Power (Note11) THD = 1% (max); f = 1kHz (Note11)

R

L

=4Ω (LM4854LD)

R

L

=8Ω

1.0

380 350

W

mW (min)

THD = 10% (max); f = 1kHz (Note11)

RL=4Ω (LM4854LD)
R

L

=8Ω

1.1

530

W

mW

THD+N Total Harmonic Distortion+Noise 20Hz ≤ f

IN

≤ 20kHz

R

L

=4Ω,PO= 800mW (LM4854LD)

R

L

=8Ω,PO= 150mW

0.3

0.21

%
%

f

IN

= 1kHz

R

L

=4Ω,PO= 500mW (LM4854LD)

R

L

=8Ω,PO= 150mW

0.1

0.075

%
%

S/N Signal-to-Noise Ratio f

IN

= 1kHz, C

BYPASS

= 1.0µF

P

O

= 900mW, RL=8Ω 90 dB

LM4854

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Electrical Characteristics : SE Operation (VDD= 3.0V) (Notes 4, 9)

The following specifications apply for for the circuit shown in Figure 1 and a measurement bandwith of 20Hz to 80kHz, unless
otherwise specified. Limits apply for T

A

= 25˚C.

Symbol Parameter Conditions LM4854 Units

(Limits)

Typical

(Note 8)

Limit

(Notes 9,

10)

P

O

Output Power (Note 11) THD+N = 1.0%, f = 1kHz, RL=32Ω

THD+N = 10%, f = 1kHz, R

L

=32Ω

THD+N = 1.0%, f = 1kHz, R

L

=16Ω

THD+N = 10%, f = 1kHz, R

L

=16Ω

32

60

57
100

27

38

mW(min)

mW

mW (min)

mW

THD+N Total Harmonic Distortion+Noise 20Hz ≤ f

IN

= ≤ 20kHz

R

L

=32Ω,PO= 30mW 0.3 %

VOUT Output Voltage Swing THD = 0.5%, R

L

=5kΩ 2.4 V

P-P

XTALK Channel Separation fIN= 1kHz, C

BYPASS

= 1.0µF, RL=32Ω 55 dB

S/N Signal-to-Noise Ratio f

IN

= 1kHz, C

BYPASS

= 1.0µF

P

O

= 30mW, RL=32Ω

TBD dB

Note 2: All voltages are measured with respect to the GND pin unless other wise specified.

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 that
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: 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 P

DMAX

=(T

JMAX-TA

)/θJAor the number given in Absolute Maximum Ratings, whichever is lower. For the LM4854, see power derating

currents for more information.

Note 5: Human body model, 100pF discharged through a 1.5kΩ resistor.

Note 6: Machine Model, 220pF-240pF discharged through all pins.

Note 7: The given θ

JA

is for an LM4854 packaged in an LDA14A with the Exposed-DAP soldered to an exposed 2in2 area of 1oz printed circuit board copper.

Note 8: Typicals are measured at 25˚C and represent the parametric norm.

Note 9: Limits are guaranteed to National’s AOQL (Average Outgoing Quality Level).

Note 10: Datasheet minimum and maximum specification limits are guaranteed by design, test, or statistical analysis.

Note 11: Output power is measured at the amplifier’s package pins.

Note 12: When driving 4Ω loads and operating on a 5V supply, the LM4854LD must be mounted to a circuit board that has a minimum of 2.5in2 of exposed,

uninterrupted copper area connected to the LLP package’s exposed DAP.

LM4854

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External Components Description

See Figure 1.

Components Functional Description

1. R

i

This is the inverting input resistance that, along with Rf, sets the closed-loop gain. Input resistance Riand
input capacitance C

i

form a high pass filter. The filter’s cutoff frequency is fc= 1/2πRiCi.

2. C

i

This is the input coupling capacitor. It blocks DC voltage at the amplifier’s inverting input. Ciand Ricreate a
highpass filter. The filter’s cutoff frequency is f

c

= 1/2πRiCi. Refer to the Application Information section,

SELECTING EXTERNAL COMPONENTS, for an explanation of determining C

i

’s value.

3. R

f

This is the feedback resistance that, along with Ri, sets the closed-loop gain.

4. C

s

The supply bypass capacitor. Refer to the POWER SUPPLY BYPASSING section for information about
properly placing, and selecting the value of, this capacitor.

5. C

B

This capacitor filters the half-supply voltage present on the BYPASS pin. Refer to the Application
Information section, SELECTING EXTERNAL COMPONENTS, for information about properly placing, and
selecting the value of, this capacitor..

Typical Performance Characteristics

THD+N vs Frequency THD+N vs Frequency

200382D8

LM4854LD

V

DD

= 5V, RL=4Ω (BTL),
P

OUT

= 1000mW

200382D9

LM4854LD

V

DD

= 5V, RL=4Ω (BTL),

P

OUT

= 400mW

THD+N vs Frequency THD+N vs Frequency

200382C0

VDD= 5V, RL=8Ω (BTL),

P

OUT

= 400mW

200382B8

VDD= 5V, RL=16Ω (SE),

P

OUT

= 50mW

LM4854

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