NSC LM4867MTX, LM4867MTEX, LM4867MTE, LM4867MT, LM4867LQX Datasheet

LM4867

Output-Transient-Free Dual 2.1W Audio Amplifier Plus
No Coupling Capacitor Stereo Headphone Function

General Description

The LM4867 is a dual bridge-connected audio power ampli­fier which, when connected to a 5V supply, will deliver 2.1W
toa4Ωload (Note 1) or 2.4W to a 3Ω load (Note 2) with less
than 1.0% THD+N. The LM4867 uses advanced, latest gen­eration circuitry to eliminate all traces of clicks and pops
when the supply voltage is first applied. The amplifier has a
headphone-amplifier-select input pin. It is used to switch the
amplifiers from bridge to single-ended mode for driving
headphones. A new circuit topology eliminates headphone
output coupling capacitors. A MUX control pin allows selec­tion between the two sets of stereo input signals. The MUX
control can also be used to select between two different
customer-specified closed-loop responses.

Boomer audio power amplifiers are designed specifically to
provide high quality output power from a surface mount
package and require few external components. To simplify
audio system design, the LM4867 combines dual bridge
speaker amplifiers and stereo headphone amplifiers in one
package.

The LM4867 features an externally controlled power-saving
micropower shutdown mode, a stereo headphone amplifier
mode, and thermal shutdown protection.

Note 1: An LM4867LQ or LM4867MTE that has been properly mounted to
a circuit board will deliver 2.1W into 4Ω. The Mux control can also be used to
select two different closed-loop responses. LM4867MT will deliver 1.1W into
8Ω. See the Application Information sections for further information concern­ing the LM4867LQ and the LM4867MT.

Note 2: An LM4867LQ or LM4867MTE that has been properly mounted to a
circuit board and forced-air cooled will deliver 2.4W into 3Ω.

Key Specifications

n POat 1% THD+N
n LM4867LQ, 3Ω load 2.4W (typ)
n LM4867LQ, 4Ω load 2.1W (typ)
n LM4867MTE, 4Ω 1.9W (typ)
n LM4867MT, 8Ω 1.1W (typ)
n Single-ended mode - THD+N at 75mW into 32Ω 0.5%

(max)

n Shutdown current 0.7µA (typ)

Features

n Advanced “click and pop” suppression circuitry
n Eliminates headphone amplifier output coupling

capacitors

n Stereo headphone amplifier mode
n Input mux control and two separate inputs per channel
n Thermal shutdown protection circuitry
n LLP, TSSOP, and exposed-DAP TSSOP packaging

available

Applications

n Multimedia monitors
n Portable and desktop computers
n Portable audio systems

Typical Application

Boomer®is a registered trademark of National Semiconductor Corporation.

DS200013-31

*

Refer to the Application Information section titled PROPER SELECTION OF EXTERNAL COMPONENTS for details concerning the value of CB.

FIGURE 1. Typical Audio Amplifier Application Circuit

(Pin out shown for the 24-pin Exposed-DAP LLP package. Numbers in ( ) are for the 20-pin MTE and MT

packages.)

February 2001

LM4867 Output-Transient-Free Dual 2.1W Audio Amplifier Plus No Coupling Capacitor Stereo

Headphone Function

© 2001 National Semiconductor Corporation DS200013 www.national.com

Connection Diagram

Connection Diagram

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Top View

Order Number LM4867MT, LM4867MTE

See NS Package Number MTC20 for TSSOP

See NS Package Number MXA20A for Exposed-DAP TSSOP

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Top View

Order Number LM4867LQ

See NS Package Number LQA24A for Exposed-DAP LLP

LM4867

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Absolute Maximum Ratings (Note 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 3 (MT, MTE), Pin 2 (LQ) 2000V

Pin 3 (MT, MTE), Pin 2 (LQ) 8000V
ESD Susceptibility (Note 6) 200V
Junction Temperature 150˚C
Solder Information

Small Outline Package

Vapor Phase (60 sec.) 215˚C
Infrared (15 sec.) 220˚C

See AN-450 “Surface Mounting and their Effects on
Product Reliablilty” for other methods of soldering surface
mount devices.

Thermal Resistance

θ

JC

(typ)—MTC20 20˚C/W

θ

JA

(typ)—MTC20 80˚C/W

θ

JC

(typ)—MXA20A 2˚C/W

θ

JA

(typ)—MXA20A 41˚C/W (Note 7)

θ

JA

(typ)—MXA20A 51˚C/W (Note 8)

θ

JA

(typ)—MXA20A 90˚C/W (Note 9)

θ

JC

(typ)—LQA24A 3.0˚C/W

θ

JA

(typ)—LQA24A TBD˚C/W (Note 10)

θ

JA

(typ)—LQA24A TBD˚C/W (Note 11)

θ

JA

(typ)—LQA24A TBD˚C/W (Note 12)

Operating Ratings

Temperature Range

T

MIN

≤ TA≤ T

MAX

−40˚C ≤ TA≤ 85˚C

Supply Voltage 2.0V ≤ V

DD

≤ 5.5V

Electrical Characteristics for Entire IC (Notes 3, 13)

The following specifications apply for VDD= 5V unless otherwise noted. Limits apply for TA= 25˚C.

Symbol Parameter Conditions LM4867 Units

(Limits)

Typical Limit

(Note 14) (Note 15)

V

DD

Supply Voltage 2 V (min)

5.5 V (max)

I

DD

Quiescent Power Supply Current VIN= 0V, IO= 0A (Note 16) , HP-IN = 0V 7.5 15 mA (max)

V

IN

= 0V, IO= 0A (Note 16) , HP-IN = 4V 3.0 6 mA (max)

I

SD

Shutdown Current VDDapplied to the SHUTDOWN pin 0.7 2 µA (max)

Electrical Characteristics for Bridged-Mode Operation (Notes 3, 13)

The following specifications apply for VDD= 5V unless otherwise specified. Limits apply for TA= 25˚C.

Symbol Parameter Conditions LM4867 Units

(Limits)

Typical Limit

(Note 14) (Note 15)

V

OS

Output Offset Voltage VIN= 0V 5 50 mV (max)

P

O

Output Power (Note 17) THD = 1%, f = 1kHz

LM4867MTE, R

L

=3Ω(Note 18) 2.2 W

LM4867LQ, R

L

=3Ω(Note 18) 2.2 W

LM4867MTE, R

L

=4Ω(Note 19) 1.9 W

LM4867LQ, R

L

=4Ω(Note 19) 1.9 W

LM4867, R

L

=8Ω 1.1 1.0 W (min)

THD+N = 10%, f = 1kHz

LM4867MTE, R

L

=3Ω(Note 18) 3.0 W

LM4867LQ, R

L

=3Ω(Note 18) 3.0 W

LM4867MTE, R

L

=4Ω(Note 19) 2.6 W

LM4867LQ, R

L

=4Ω(Note 19) 2.6 W

LM4867, R

L

=8Ω 1.5 W

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

L

=32Ω 0.34 W

LM4867

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Electrical Characteristics for Bridged-Mode Operation (Notes 3, 13) (Continued)

The following specifications apply for VDD= 5V unless otherwise specified. Limits apply for TA= 25˚C.

Symbol Parameter Conditions LM4867 Units

(Limits)

Typical Limit

(Note 14) (Note 15)

THD+N Total Harmonic Distortion+Noise 20Hz ≤ f ≤ 20kHz, A

VD

=2

LM4867MTE, R

L

=4Ω,PO=2W

LM4867LQ, R

L

=4Ω,PO=2W

LM4867, R

L

=8Ω,PO=1W

0.3

0.3

0.3

%
%
%

PSRR Power Supply Rejection Ratio V

DD

= 5V, V

RIPPLE

= 200 mV

RMS,RL

=8Ω,

C

B

= 2.2µF

67 dB

X

TALK

Channel Separation f = 1 kHz, CB= 2.2µF 80 dB

SNR Signal To Noise Ratio V

DD

= 5V, PO= 1.1W, RL=8Ω 97 dB

Electrical Characteristics for Single-Ended Operation (Notes 3, 13)

The following specifications apply for VDD= 5V unless otherwise specified. Limits apply for TA= 25˚C.

Symbol Parameter Conditions LM4867 Units

(Limits)

Typical Limit

(Note 14) (Note 15)

V

OS

Output Offset Voltage VIN= 0V 5 50 mV (max)

P

O

Output Power THD = 0.5%, f = 1kHz, RL=32Ω 85 75 mW (min)

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

L

=8Ω(Note

20)

180 mW

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

L

=16Ω

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

L

=32Ω

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

L

=16Ω

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

L

=32Ω

165

88
208
114

mW
mW
mW
mW

V

OUT

Output Voltage Swing THD = 0.05%, RL=5kΩ 1V

P-P

THD+N Total Harmonic Distortion+Noise AV= −1, PO= 75mW, 20 Hz ≤ f ≤ 20kHz,

R

L

=32Ω

0.2 %

PSRR Power Supply Rejection Ratio C

B

= 2.2µF, V

RIPPLE

= 200mV

RMS

,

f = 1kHz

52 dB

X

TALK

Channel Separation f = 1kHz, CB= 2.2µF 60 dB

SNR Signal To Noise Ratio V

DD

= 5V, PO= 340mW, RL=8Ω 94 dB

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 donotguaranteespecific performance limits. Electrical Characteristics state DC and AC electrical specifications under particular test conditions which
guarantee specific performance limits. This assumes that the device operates within the Operating Ratings. Specifications are not guaranteed for parameters where
no limit is given. The typical value however, 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

)/θJA. For the LM4867, T

JMAX

= 150˚C. For the θJAs for different packages, please see the Application

Information section or the Absolute Maximum Ratings section.

Note 5: Human body model, 100 pF discharged through a 1.5 kΩ resistor.
Note 6: Machine model, 220 pF–240 pF discharged through all pins.
Note 7: The given θ

JA

is for an LM4867 packaged in an MXA20A with the Exposed-DAP soldered to an exposed 2in2area of 1oz printed circuit board copper.

Note 8: The given θ

JA

is for an LM4867 packaged in an MXA20A with the Exposed-DAP soldered to an exposed 1in2area of 1oz printed circuit board copper.

Note 9: The given θ

JA

is for an LM4867 packaged in an MXA20A with the Exposed-DAP not soldered to printed circuit board copper.

Note 10: The given θ

JA

is for an LM4867 packaged in an LQA24A with the Exposed-DAP soldered to an exposed 2in2area of 1oz printed circuit board copper.

Note 11: The given θ

JA

is for an LM4867 packaged in an LQA24A with the Exposed-DAP soldered to an exposed 1in2area of 1oz printed circuit board copper.

Note 12: The given θ

JA

is for an LM4867 packaged in an LQA24A with the Exposed-DAP not soldered to printed circuit board copper.

Note 13: All voltages are measured with respect to the ground (GND) pins, unless otherwise specified.
Note 14: Typicals are measured at 25˚C and represent the parametric norm.
Note 15: Limits are guaranteed to National’s AOQL (Average Outgoing Quality Level). Datasheet min/max specification limits are guaranteed by design, test, or

statistical analysis.

Note 16: The quiescent power supply current depends on the offset voltage when a practical load is connected to the amplifier.
Note 17: Output power is measured at the device terminals.
Note 18: When driving 3Ω loads from a 5V supply,the LM4867LQ, LM4867MTE, or LM4867MTE-1 must be mounted to the circuit board and forced-air cooled (450

linear-feet per minute).

Note 19: When driving 4Ω loads from a 5V supply, the LM4867LQ, LM4867MTE or LM4867MTE-1 must be mounted to the circuit board.

LM4867

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Electrical Characteristics for Single-Ended Operation (Notes 3, 13) (Continued)

Note 20: See Application Information section ’Single-Ended Output Power Performance and Measurement Considerations’ for more information.

Typical Performance Characteristics
MTE- and LQ- Specific Characteristics

Note 21: This curve shows the LM4867MTE’s thermal dissipation ability at different ambient temperatures given these conditions:

500LFPM + JEDEC board: The part is soldered to a 1S2P 20-lead exposed-DAP TSSOP test board with 500 linear feet per minute of forced-air flow across

it. Board information - copper dimensions: 74x74mm, copper coverage: 100% (buried layer) and 12% (top/bottom layers), 16 vias under the exposed-DAP.

500LFPM + 2.5in

2

: The part is soldered to a 2.5in2, 1 oz. copper plane with 500 linear feet per minute of forced-air flow across it.

2.5in

2

: The part is soldered to a 2.5in2, 1oz. copper plane.

Not Attached: The part is not soldered down and is not forced-air cooled.

LM4867MTE
THD+N vs Output Power

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LM4867MTE
THD+N vs Frequency

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LM4867LQ
THD+N vs Output Power

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LM4867LQ
THD+N vs Frequency

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LM4867MTE
THD+N vs Output Power

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LM4867LQ
THD+N vs Output Power

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LM4867LQ, LM4867MTE
Power Dissipation vs Power Output

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LM4867LQ, LM4867MTE(Note 21)
Power Derating Curve

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LM4867

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Typical Performance Characteristics

THD+N vs Frequency

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THD+N vs Frequency

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THD+N vs Frequency

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THD+N vs Output Power

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THD+N vs Output Power

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THD+N vs Output Power

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THD+N vs Output Power

DS200013-65

THD+N vs Frequency

DS200013-63

THD+N vs Output Power

DS200013-66

THD+N vs Frequency

DS200013-64

Output Power vs
Load Resistance

DS200013-62

Power Dissipation vs
Supply Voltage

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LM4867

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Typical Performance Characteristics (Continued)

Output Power vs
Supply Voltage

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Output Power vs
Supply Voltage

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Output Power vs
Supply Voltage

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Output Power vs
Load Resistance

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Output Power vs
Load Resistance

DS200013-13

Power Dissipation vs
Output Power

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Dropout Voltage vs
Supply Voltage

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Power Derating Curve

DS200013-16

Power Dissipation vs
Output Power

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LM4867

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Typical Performance Characteristics (Continued)

Noise Floor

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Channel Separation

DS200013-19

Channel Separation

DS200013-20

Power Supply
Rejection Ratio

DS200013-21

Open Loop
Frequency Response

DS200013-22

Supply Current vs
Supply Voltage

DS200013-23

LM4867

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