National Semiconductor LM4890 Technical data

LM4890
1 Watt Audio Power Amplifier

LM4890 1 Watt Audio Power Amplifier

July 2006

General Description

The LM4890 is an audio power amplifier primarily designed
for demanding applications in mobile phones and other por­table communication device applications. It is capable of
delivering 1 watt of continuous average power to an 8Ω BTL
load with less than 1% distortion (THD+N) from a 5V
power supply.

Boomer audio power amplifiers were designed specifically to
provide high quality output power with a minimal amount of
external components. The LM4890 does not require output
coupling capacitors or bootstrap capacitors, and therefore is
ideally suited for mobile phone and other low voltage appli­cations where minimal power consumption is a primary re­quirement.

The LM4890 features a low-power consumption shutdown
mode, which is achieved by driving the shutdown pin with
logic low. Additionally, the LM4890 features an internal ther­mal shutdown protection mechanism.

The LM4890 contains advanced pop & click circuitry which
eliminates noises which would otherwise occur during
turn-on and turn-off transitions.

The LM4890 is unity-gain stable and can be configured by
external gain-setting resistors.

DC

Key Specifications

j

PSRR at 217Hz, VDD= 5V (Fig. 1) 62dB(typ.)

j

Power Output at 5.0V & 1% THD 1W(typ.)

j

Power Output at 3.3V & 1% THD 400mW(typ.)

j

Shutdown Current 0.1µA(typ.)

Features

n Available in space-saving packages: micro SMD, MSOP,

SOIC, and LLP

n Ultra low current shutdown mode
n BTL output can drive capacitive loads
n Improved pop & click circuitry eliminates noises during

turn-on and turn-off transitions

n 2.2 - 5.5V operation
n No output coupling capacitors, snubber networks or

bootstrap capacitors required

n Thermal shutdown protection
n Unity-gain stable
n External gain configuration capability

Applications

n Mobile Phones
n PDAs
n Portable electronic devices

Connection Diagrams

8 Bump micro SMD 8 bump micro SMD Marking

Top View

X - Date Code

T - Die Traceability

Top View

20019223

Order Number LM4890IBP, LM4890IBPX

See NS Package Number BPA08DDB

Boomer®is a registered trademark of National Semiconductor Corporation.

© 2006 National Semiconductor Corporation DS200192 www.national.com

G - Boomer Family

E - LM4890IBP

20019270

Connection Diagrams (Continued)

LM4890

9 Bump micro SMD 9 Bump micro SMD Marking

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Top View

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

P - LM4890IBL

200192C1

Top View

Order Number LM4890IBL, LM4890IBLX

See NS Package Number BLA09AAB

LLP Package 10 Pin LLP Marking

200192C6

Top View

200192C7

Order Number LM4890LD

See NS Package Number LDA10B

Top View

Z - Assembly Plant Date Code (M for Malacca)

XY - Digit Date Code

TT - Die Traceability

L4890 - LM4890LD

Mini Small Outline (MSOP) Package MSOP Marking

Top View

20019236

Order Number LM4890MM

Top View

G - Boomer Family

90 - LM4890MM

See NS Package Number MUA08A

Small Outline (SO) Package SO Marking

Top View

20019235

Order Number LM4890M

See NS Package Number M08A

Bottom 2 lines - Part Number

Top View

XY - Date Code

TT - Die Traceability

20019271

20019272

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Connection Diagrams (Continued)

9 Bump micro SMD 9 Bump micro SMD Marking

LM4890

Top View

Order Number LM4890ITL, LM4890ITLX

See NS Package Number TLA09AAA

Typical Application

Top View

200192D0

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

A8 - LM4890ITL

200192C1

FIGURE 1. Typical Audio Amplifier Application Circuit

20019201

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Absolute Maximum Ratings (Note 2)

If Military/Aerospace specified devices are required,

LM4890

please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.

Supply Voltage (Note 11) 6.0V

Storage Temperature −65˚C to +150˚C

Input Voltage −0.3V to V

Power Dissipation (Note 3) Internally Limited

DD

+0.3V

(9 Bump micro SMD, Note 12) 180˚C/W

θ

JA

θ

(MSOP) 56˚C/W

JC

θ

(MSOP) 190˚C/W

JA

θ

(LLP) 220˚C/W

JA

Soldering Information

See AN-1112 "microSMD Wafers Level Chip Scale
Package."

See AN-1187 "Leadless Leadframe Package (LLP)."

ESD Susceptibility (Note 4) 2000V

Junction Temperature 150˚C

Operating Ratings

Thermal Resistance

θ

(SOP) 35˚C/W

JC

θ

(SOP) 150˚C/W

JA

θ

(8 Bump micro SMD, Note 12) 220˚C/W

JA

Temperature Range

T

≤ TA≤ T

MIN

MAX

Supply Voltage 2.2V ≤ V

Electrical Characteristics VDD=5V (Notes 1, 2, 8)

The following specifications apply for the circuit shown in Figure 1 unless otherwise specified. Limits apply for T

−40˚C ≤ TA≤ 85˚C

≤ 5.5V

DD

= 25˚C.

A

LM4890

Symbol Parameter Conditions

Typical Limit

(Note 6) (Notes 7, 9)

I

DD

I

SD

V

SDIH

V

SDIL

V

OS

R

OUT-GND

P

o

T

WU

T

SD

THD+N Total Harmonic Distortion + Noise P

PSRR Power Supply Rejection Ratio

T

SDT

Quiescent Power Supply Current VIN= 0V, Io= 0A, No Load 4 8 mA (max)

V

= 0V, Io= 0A, 8Ω Load 5 10 mA (max)

IN

Shutdown Current V

SHUTDOWN

= 0V 0.1 2.0 µA (max)

Shutdown Voltage Input High 1.2 V (min)

Shutdown Voltage Input Low 0.4 V (max)

Output Offset Voltage 7 50 mV (max)

Resistor Output to GND (Note 10)

8.5

9.7 kΩ (max)

7.0 kΩ (min)

Output Power (8Ω) THD = 2% (max);f=1kHz 1.0 0.8 W

Wake-up time 170 220 ms (max)

Thermal Shutdown Temperature

(Note 14)

170

= 0.4 Wrms; f = 1kHz 0.1 %

o

V

= 200mV sine p-p

ripple

Input Terminated with 10 ohms to
ground

62 (f =

217Hz)

66 (f = 1kHz)

150 ˚C (min)

190 ˚C (max)

55 dB (min)

Shut Down Time 8 Ω load 1.0 ms (max)

Electrical Characteristics VDD=3V (Notes 1, 2, 8)

The following specifications apply for the circuit shown in Figure 1 unless otherwise specified. Limits apply for T

= 25˚C.

A

Units

(Limits)

Symbol Parameter Conditions

I

DD

I

SD

V

SDIH

V

SDIL

V

OS

R

OUT-GND

T

WU

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Quiescent Power Supply Current VIN= 0V, Io= 0A, No Load 3.5 7 mA (max)

V

= 0V, Io= 0A, 8Ω Load 4.5 9 mA (max)

IN

Shutdown Current V

SHUTDOWN

= 0V 0.1 2.0 µA (max)

Shutdown Voltage Input High 1.2 V(min)

Shutdown Voltage Input Low 0.4 V(max)

Output Offset Voltage 7 50 mV (max)

Resistor Output to Gnd (Note 10)

Wake-up time 120 180 ms (max)

LM4890

Typical Limit

(Note 6) (Notes 7, 9)

8.5

9.7 kΩ (max)

7.0 kΩ (min)

Units

(Limits)

Electrical Characteristics VDD=3V(Notes 1, 2, 8)

The following specifications apply for the circuit shown in Figure 1 unless otherwise specified. Limits apply for T
25˚C. (Continued)

LM4890

=

A

Symbol Parameter Conditions

P

o

T

SD

THD+N Total Harmonic Distortion + Noise P

PSRR Power Supply Rejection Ratio

Output Power (8Ω) THD = 1% (max); f = 1kHz 0.31 0.28 W

Thermal Shutdown Temperature

= 0.15Wrms; f = 1kHz 0.1 %

o

V

= 200mV sine p-p

ripple

(Note 14)

Input terminated with 10 ohms to
ground

LM4890

Typical Limit

(Note 6) (Notes 7, 9)

170

56 (f =

150 ˚C(min)

190 ˚C(max)

45 dB(min)

217Hz)

62 (f = 1kHz)

Units

(Limits)

Electrical Characteristics VDD= 2.6V (Notes 1, 2, 8)

The following specifications apply for for the circuit shown in Figure 1 unless otherwise specified. Limits apply for T

LM4890

Symbol Parameter Conditions

Typical Limit

(Note 6) (Notes 7, 9)

I

DD

I

SD

P

0

THD+N Total Harmonic Distortion + Noise P

PSRR Power Supply Rejection Ratio

Note 1: All voltages are measured with respect to the ground pin, unless otherwise specified.

Note 2: 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 andAC 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 3: The maximum power dissipation must be derated at elevated temperatures and is dictated by T
allowable power dissipation is P
curves for additional information.

Note 4: Human body model, 100 pF discharged through a 1.5 kΩ resistor.

Note 5: Machine Model, 220 pF–240 pF discharged through all pins.

Note 6: Typicals are measured at 25˚C and represent the parametric norm.

Note 7: Limits are guaranteed to National’s AOQL (Average Outgoing Quality Level).

Note 8: For micro SMD only, shutdown current is measured in a Normal Room Environment. Exposure to direct sunlight will increase I

Note 9: Datasheet min/max specification limits are guaranteed by design, test, or statistical analysis.

Note 10: ROUT is measured from each of the output pins to ground. This value represents the parallel combination of the 10k ohm output resistors and the two 20k

ohm resistors.

Note 11: If the product is in shutdown mode and V
If the source impedance limits the current to a max of 10 ma, then the part will be protected. If the part is enabled when V
no damage will occur, although operational life will be reduced. Operation above 6.5V with no current limit will result in permanent damage.

Note 12: All bumps have the same thermal resistance and contribute equally when used to lower thermal resistance. All bumps must be connected to achieve
specified thermal resistance.

Note 13: Maximum power dissipation (P
Equation 1 shown in the Application section. It may also be obtained from the power dissipation graphs.

Note 14: PSRR is a function of system gain. Specifications apply to the circuit in Figure 1 where A
of gain increase. A system gain of 10 represents a gain increase of 14dB. PSRR will be reduced by 14dB and applies to all operating voltages.

Quiescent Power Supply Current VIN= 0V, Io= 0A, No Load 2.6 mA (max)

Shutdown Current V

Output Power (8Ω)
Output Power (4Ω)

(Note 14)

DMAX

=(T

)/θJAor the number given inAbsolute Maximum Ratings, whichever is lower. For the LM4890, see power derating

JMAX–TA

exceeds 6V (to a max of 8V VDD), then most of the excess current will flow through the ESD protection circuits.

DD

) in the device occurs at an output power level significantly below full output power. P

DMAX

SHUTDOWN

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

= 0.1Wrms; f = 1kHz 0.08 %

o

V

ripple

Input Terminated with 10 ohms to
ground

= 0V 0.1 µA (max)

0.2

0.22

= 200mV sine p-p

44 (f =

217Hz)

44 (f = 1kHz)

, θJA, and the ambient temperature TA. The maximum

JMAX

by a maximum of 2µA.

SD

is greater than 5.5V and less than 6.5V,

DD

can be calculated using

DMAX

= 2. Higher system gains will reduce PSRR value by the amount

V

= 25˚C.

A

(Limits)

Units

W
W

dB

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External Components Description (Figure 1)

LM4890

Components Functional Description

1. R

2. C

3. R

4. C

5. C

BYPASS

Inverting input resistance which sets the closed-loop gain in conjunction with Rf. This resistor also forms a

IN

high pass filter with C

Input coupling capacitor which blocks the DC voltage at the amplifier’s input terminals. Also creates a

IN

highpass filter with R

at fC= 1/(2π RINCIN).

IN

at fc= 1/(2π RINCIN). Refer to the section, Proper Selection of External

IN

Components, for an explanation of how to determine the value of C

Feedback resistance which sets the closed-loop gain in conjunction with RIN.

f

Supply bypass capacitor which provides power supply filtering. Refer to the section, Power Supply

S

Bypassing, for information concerning proper placement and selection of the supply bypass capacitor,

BYPASS

.

C

Bypass pin capacitor which provides half-supply filtering. Refer to the section, Proper Selection of External
Components, for information concerning proper placement and selection of C

.

IN

.

BYPASS

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Typical Performance Characteristics

LM4890

THD+N vs Frequency

= 5V, 8Ω RL, and PWR = 250mW, AV=2

at V

DD

at V

THD+N vs Frequency

at VDD= 3.3V, 8Ω RL, and PWR = 150mW, AV=2

20019237 20019238

THD+N vs Frequency

= 3V, RL=8Ω, PWR = 250mW, AV=2

DD

@

THD+N vs Frequency

VDD= 2.6V, RL=8Ω, PWR = 100mW, AV=2

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20019290

THD+N vs Frequency

@

VDD= 2.6V, RL=4Ω, PWR = 100mW, AV=2

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Typical Performance Characteristics (Continued)

LM4890

THD+N vs Power Out

@

VDD= 5V, RL=8Ω, 1kHz, AV=2

200192C9

THD+N vs Power Out

@

VDD= 3V, RL=8Ω, 1kHz, AV=2

THD+N vs Power Out

@

VDD= 3.3V, RL=8Ω, 1kHz, AV=2

20019242

THD+N vs Power Out

@

VDD= 2.6V, RL=8Ω, 1kHz, AV=2

20019291

THD+N vs Power Out

@

VDD= 2.6V, RL=4Ω, 1kHz, AV=2

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Typical Performance Characteristics (Continued)

LM4890

@

Power Supply Rejection Ratio (PSRR)

V

= 5V, V

DD

=8Ω,RIN=10Ω

R

L

ripple

= 200mvp-p

AV=2

20019245 20019273

Power Supply Rejection Ratio (PSRR)@AV=4

V

= 5V, V

DD

=8Ω,RIN=10Ω

R

L

ripple

= 200mvp-p

Power Supply Rejection Ratio (PSRR)

V

DD

= 5V, V

R

L

=8Ω,RIN= Float

ripple

= 200mvp-p

Power Supply Rejection Ratio (PSRR)

V

DD

= 5V, V

R

L

=8Ω,RIN= Float

ripple

= 200mvp-p

@

AV=2

@

AV=4

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