TEXAS INSTRUMENTS TPA741 Technical data

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1
2
3
4

8
7
6
5

SHUTDOWN

BYPASS

IN+
IN–

VO–
GND
V

DD

VO+

D OR DGN PACKAGE

(TOP VIEW)

Audio

Input

Bias

Control

V

DD

700 mW

6

5

7

VO+

V

DD

1

24BYPASS

IN–

VDD/2

C

I

R

I

C

S

C

B

R

F

SHUTDOWN

VO– 8

GND

From System Control

3 IN+

–

+

–

+

700-mW MONO LOW-VOLTAGE AUDIO POWER

AMPLIFIER WITH DIFFERENTIAL INPUTS

FEATURES DESCRIPTION

• Fully Specified for 3.3-V and 5-V Operation

• Wide Power Supply Compatibility 2.5 V - 5.5 V

• Output Power for R

– 700 mW at V
– 250 mW at V

DD
DD

• Integrated Depop Circuitry

• Thermal and Short-Circuit Protection

• Surface-Mount Packaging

– SOIC
– PowerPAD™ MSOP

= 8 Ω

L

= 5 V
= 3.3 V load at less than 0.6% THD+N throughout voice band

TPA741

SLOS316C – JUNE 2000 – REVISED JUNE 2004

The TPA741 is a bridge-tied load (BTL) audio power
amplifier developed especially for low-voltage appli­cations where internal speakers are required.
Operating with a 3.3-V supply, the TPA741 can
deliver 250-mW of continuous power into a BTL 8-Ω

frequencies. Although this device is characterized out
to 20 kHz, its operation is optimized for narrower
band applications such as wireless communications.
The BTL configuration eliminates the need for exter­nal coupling capacitors on the output in most appli­cations, which is particularly important for small
battery-powered equipment. This device features a
shutdown mode for power-sensitive applications with
a supply current of 7 µA during shutdown. The
TPA741 is available in an 8-pin SOIC surface-mount
package and the surface-mount PowerPAD™ MSOP,
which reduces board space by 50% and height by
40%.

PowerPAD is a trademark of Texas Instruments.

PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas
Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

Copyright © 2000–2004, Texas Instruments Incorporated

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TPA741

SLOS316C – JUNE 2000 – REVISED JUNE 2004

These devices have limited built-in ESD protection. The leads should be shorted together or the device
placed in conductive foam during storage or handling to prevent electrostatic damage to the MOS gates.

AVAILABLE OPTIONS

PACKAGED DEVICES

T

A

SMALL OUTLINE

(1)

(D) (DGN)

–40°C to 85°C TPA741D TPA741DGN AJD

(1) In the D package, the maximum output power is thermally limited to 350 mW; 700-mW peaks can be driven, as long as the RMS value

is less than 350 mW.

(2) The D and DGN packages are available taped and reeled. To order a taped and reeled part, add the suffix R to the part number (e.g.,

TPA741DR).

Terminal Functions

TERMINAL

NAME NO.

BYPASS 2 I
GND 7 GND is the ground connection.

IN- 4 I IN- is the inverting input. IN- is typically used as the audio input terminal.
IN+ 3 I IN+ is the noninverting input. IN+ is typically tied to the BYPASS terminal for SE operations.
SHUTDOWN 1 I SHUTDOWN places the entire device in shutdown mode when held high.
V

DD

V

O+

V

O-

I/O DESCRIPTION

BYPASS is the tap to the voltage divider for internal mid-supply bias. This terminal should be connected
to a 0.1-µF to 2.2-µF capacitor when used as an audio amplifier.

6 V
5 O V

is the supply voltage terminal.

DD

is the positive BTL output.

O+

8 O VO-is the negative BTL output.

(2)

MSOP

MSOP SYMBOLIZATION

ABSOLUTE MAXIMUM RATINGS

over operating free-air temperature range (unless otherwise noted)

V
V

T
T
T

(1) Stresses beyond those listed under "absolute maximum ratings" may cause permanent damage to the device. These are stress ratings

Supply voltage 6 v

DD

Input voltage –0.3 V to V

I

Continuous total power dissipation Internally limited (see Dissipation Rating Table)
Operating free-air temperature range –40°C to 85°C

A

Operating junction temperature range –40°C to 150°C

J

Storage temperature range –65°C to 150°C

stg

Lead temperature 1,6 mm (1/16 inch) from case for 10 seconds 260°C

only, and functional operation of the device at these or any other conditions beyond those indicated under "recommended operating
conditions" is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.

(1)

UNIT

+0.3 V

DD

DISSIPATION RATING TABLE

PACKAGE TA≤ 25°C DERATING FACTOR TA= 70°C TA= 85°C

D 725 mW 5.8 mW/°C 464 mW 377 mW

DGN 2.14 W

(1) See the Texas Instruments document, PowerPAD Thermally Enhanced Package Application Report

(SLMA002), for more information on the PowerPAD package. The thermal data was measured on a
PCB layout based on the information in the section entitled Texas Instruments Recommended Board
for PowerPAD of that document.

(1)

17.1 mW/°C 1.37 W 1.11 W

2

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SLOS316C – JUNE 2000 – REVISED JUNE 2004

RECOMMENDED OPERATING CONDITIONS

MIN MAX UNIT

V

DD

V

IH

V

IL

T

A

Supply voltage, 2.5 5.5 V
High-level voltage (SHUTDOWN) 0.9V

DD

Low-level voltage (SHUTDOWN) 0.1V
Operating free-air temperature –40 85 °C

ELECTRICAL CHARACTERISTICS

at specified free-air temperature, V

PARAMETER TEST CONDITIONS MIN TYP MAX UNIT

|V

| Output offset voltage (measured differentially) SHUTDOWN = 0 V, RL= 8 Ω, RF = 10 kΩ 20 mV

OS

PSRR Power supply rejection ratio V
I

I
|IIH| SHUTDOWN, V

|IIL| SHUTDOWN, V

Supply current SHUTDOWN = 0 V, RF = 10 kΩ 1.35 2.5 mA

DD

Supply current, shutdown mode

DD(SD)

(see Figure 6 )

= 3.3 V, TA= 25°C (unless otherwise noted)

DD

= 3.2 V to 3.4 V 85 dB

DD

SHUTDOWN = VDD, RF = 10 kΩ 7 50 µA

= 3.3 V, Vi= 3.3 V 1 µA

DD

= 3.3 V, Vi= 0 V 1 µA

DD

OPERATING CONDITIONS

V

= 3.3 V, TA= 25°C, RL= 8 Ω

DD

PARAMETER TEST CONDITIONS MIN TYP MAX UNIT

P

O

Output power, See
THD + N Total harmonic distortion plus noise PO= 250 mW, f = 200 Hz to 4 kHz, See Figure 7 0.55%
B

OM

B

1

k

SVR

V

n

Maximum output power bandwidth AV= -2 V/V, THD = 2%, See Figure 7 20 kHz

Unity-gain bandwidth Open loop, See Figure 15 1.4 MHz

Supply ripple rejection ratio f = 1 kHz, CB= 1 µF, See Figure 2 79 dB

Noise output voltage AV= -1 V/V, CB= 0.1 µF, See Figure 19 17 µV(rms)

(1) Output power is measured at the output terminals of the device at f = 1 kHz.

(1)

THD = 0.5%, See Figure 9 250 mW

TPA741

V
V

DD

ELECTRICAL CHARACTERISTICS

at specified free-air temperature, V

PARAMETER TEST CONDITIONS MIN TYP MAX UNIT

|V

| Output offset voltage (measured differentially) SHUTDOWN = 0 V, RL= 8 Ω, RF = 10 kΩ 20 mV

OS

PSRR Power supply rejection ratio V
I

I
|IIH| SHUTDOWN, V

|IIL| SHUTDOWN, V

Supply current SHUTDOWN = 0 V, RF = 10 kΩ 1.45 2.5 mA

DD

Supply current, shutdown mode (see Fig-

DD(SD)

ure 4 )

= 5 V, TA= 25°C (unless otherwise noted)

DD

= 4.9 V to 5.1 V 78 dB

DD

SHUTDOWN = VDD, RF = 10 kΩ 50 100 µA

= 5.5 V, Vi= V

DD

= 5.5 V, Vi= 0 V 1 µA

DD

DD

1 µA

3

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Audio

Input

Bias

Control

V

DD

6

5

7

VO+

V

DD

1

24BYPASS

IN–

VDD/2

C

I

R

I

C

S

C

B

R

F

SHUTDOWN

VO– 8

R

L = 8

Ω

GND

3 IN+

–

+

–

+

TPA741

SLOS316C – JUNE 2000 – REVISED JUNE 2004

OPERATING CHARACTERISTICS

V

= 5 V, TA= 25°C, RL= 8Ω

DD

PARAMETER TEST CONDITIONS MIN TYP MAX UNIT

P

O

THD + N Total harmonic distortion plus noise 0.5%
B

OM

B

1

k

SVR

V

n

Output power THD = 0.5%, See Figure 13 700

PO= 250 mW, f = 200 Hz to 4 kHz,

See Figure 11
Maximum output power bandwidth AV= -2 V/V, THD = 2%, See Figure 11 20 kHz
Unity-gain bandwidth Open loop, See Figure 16 1.4 MHz
Supply ripple rejection ratio f = 1 kHz, CB= 1 µF, See Figure 2 80 dB
Noise output voltage AV= -1 V/V, CB= 0.1 µF, See Figure 20 17 µV(rms)

(1) The DGN package, properly mounted, can conduct 700-mW RMS power continuously. The D package can only conduct 350-mW RMS

power continuously with peaks to 700 mW.

PARAMETER MEASUREMENT INFORMATION

(1)

mW

Figure 1. BTL Mode Test Circuit

4

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−50

−60

−80

−100
20 100 1k

−30

−20

f − Frequency − Hz

0

10k 20k

−10

−40

−70

−90

VDD = 5 V

VDD = 3.3 V

RL = 8 Ω
CB = 1 µF

k

SVR

− Supply Ripple Rejection Ratio − dB

VDD − Supply Voltage − V

1.8

0.8

0.6

1

3 4

5.5

5

I

DD

− Supply Current − mA

2.5 3.5 4.5

1.6

1.2

1.4

SHUTDOWN = 0 V
RF = 10 kΩ

k

SVR

I

DD

P

Supply ripple rejection ratio vs Frequency 2
Supply current vs Supply voltage 3, 4

Output power

O

THD+N Total harmonic distortion plus noise

Open-loop gain and phase vs Frequency 15, 16

Closed-loop gain and phase vs Frequency 17, 18
V
P

Output noise voltage vs Frequency 19, 20

n

Power dissipation vs Output power 21, 22

D

TPA741

SLOS316C – JUNE 2000 – REVISED JUNE 2004

TYPICAL CHARACTERISTICS

Table of Graphs

FIGURE

vs Supply voltage 5
vs Load resistance 6
vs Frequency 7, 8, 11, 12
vs Output power 9, 10, 13, 14

SUPPLY RIPPLE REJECTION RATIO SUPPLY CURRENT

vs vs

FREQUENCY SUPPLY VOLTAGE

Figure 2. Figure 3.

5

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VDD − Supply Voltage − V

20
10

0

3 43.5 4.5

60

5

30

SHUTDOWN = V

DD

RF = 10 kΩ

40

50

5.52.5

I

DD

− Supply Current − Aµ

70

80

90

VDD − Supply Voltage − V

600

400

200

0

2.5 3.53 4 5.5

1000

P

4.5 5

O

− Output Power − mW

800

THD+N 1%
f = 1 kHz

RL = 32 Ω

RL = 8 Ω

RL − Load Resistance − Ω

300

200

100

0

16 3224 40 64

800

8

P

48 56

O

− Output Power − mW

400

THD+N = 1%
f = 1 kHz

VDD = 5 V

500

600

VDD = 3.3 V

700

f − Frequency − Hz

THD+N −Total Harmonic Distortion + Noise − %

AV = −2 V/V

VDD = 3.3 V
PO = 250 mW
RL = 8 Ω

20 1k 10k

1

0.01

10

0.1

20k100

AV = −20 V/V

AV = −10 V/V

TPA741

SLOS316C – JUNE 2000 – REVISED JUNE 2004

SUPPLY CURRENT OUTPUT POWER

vs vs

SUPPLY VOLTAGE SUPPLY VOLTAGE

Figure 4. Figure 5.

OUTPUT POWER TOTAL HARMONIC DISTORTION + NOISE

vs vs

LOAD RESISTANCE FREQUENCY

6

Figure 6. Figure 7.

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f − Frequency − Hz

THD+N −Total Harmonic Distortion + Noise − %

PO = 125 mW

VDD = 3.3 V
RL = 8 Ω
AV = −2 V/V

20 1k 10k

1

0.01

10

0.1

20k100

PO = 50 mW

PO = 250 mW

PO − Output Power − W

THD+N −Total Harmonic Distortion + Noise − %

0 0.15 0.4

1

0.01

10

0.1

0.2 0.25 0.3 0.35

VDD = 3.3 V
f = 1 kHz
AV = −2 V/V

0.05 0.1

RL = 8 Ω

PO − Output Power − W

THD+N −Total Harmonic Distortion + Noise − %

f = 20 kHz

VDD = 3.3 V
RL = 8 Ω
CB = 1 µF
AV = −2 V/V

0.01 0.1 1

1

0.01

10

0.1

f = 1 kHz

f = 10 kHz

f = 20 Hz

f − Frequency − Hz

THD+N −Total Harmonic Distortion + Noise − %

AV =− 2 V/V

VDD = 5 V
PO = 700 mW
RL = 8 Ω

20 1k 10k

1

0.01

10

0.1

20k100

AV = −20 V/V

AV = −10 V/V

TPA741

SLOS316C – JUNE 2000 – REVISED JUNE 2004

TOTAL HARMONIC DISTORTION + NOISE TOTAL HARMONIC DISTORTION + NOISE

vs vs

FREQUENCY OUTPUT POWER

Figure 8. Figure 9.

TOTAL HARMONIC DISTORTION + NOISE TOTAL HARMONIC DISTORTION + NOISE

vs vs

OUTPUT POWER FREQUENCY

Figure 10. Figure 11.

7

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f − Frequency − Hz

THD+N −Total Harmonic Distortion + Noise − %

PO = 700 mW

VDD = 5 V
RL = 8 Ω
AV = −2 V/V

20 1k 10k

1

0.01

10

0.1

20k100

PO = 50 mW

PO = 350 mW

PO − Output Power − W

0.1 0.2 10.4 0.5 0.7 0.8

THD+N −Total Harmonic Distortion + Noise − %

RL = 8 Ω

VDD = 5 V
f = 1 kHz
AV = −2 V/V

1

0.01

10

0.1

0.3 0.6 0.9

10

0

−20

−30

20

30

f − Frequency − kHz

80

−10

180°

−180°

Phase

60°

−60°

Open-Loop Gain − dB

Phase

1

10

1

10

2

10

3

10

4

50
40

60

70

140°
100°

20°

−20°

−100°

−140°

VDD = 3.3 V
RL = Open

Gain

PO − Output Power − W

THD+N −Total Harmonic Distortion + Noise − %

f = 20 Hz

VDD = 5 V
RL = 8 Ω
CB = 1 µF
AV = −2 V/V

0.01 0.1 1

1

0.01

10

0.1

f = 1 kHz

f = 10 kHz

f = 20 kHz

TPA741

SLOS316C – JUNE 2000 – REVISED JUNE 2004

TOTAL HARMONIC DISTORTION + NOISE TOTAL HARMONIC DISTORTION + NOISE

vs vs

FREQUENCY OUTPUT POWER

Figure 12. Figure 13.

TOTAL HARMONIC DISTORTION + NOISE OPEN-LOOP GAIN AND PHASE

vs vs

OUTPUT POWER FREQUENCY

8

Figure 14. Figure 15.