TPA122DR [TI]
Dual Audio Amplifier ; 双路音频放大器\n
| 型号： | TPA122DR |
| 厂家： | 
TEXAS INSTRUMENTS |
| 描述： | Dual Audio Amplifier
|
| 文件： | 总25页 (文件大小：440K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
TPA122
150-mW STEREO AUDIO POWER AMPLIFIER
SLOS211C – AUGUST1998 – REVISED MARCH 2000
D OR DGN PACKAGE
(TOP VIEW)
150 mW Stereo Output
PC Power Supply Compatible
– Fully Specified for 3.3 V and 5 V
Operation
V 1
O
V
DD
1
2
3
4
8
7
6
5
IN–
BYPASS
GND
V 2
O
– Operation to 2.5 V
IN2–
Pop Reduction Circuitry
SHUTDOWN
Internal Mid-Rail Generation
Thermal and Short-Circuit Protection
Surface-Mount Packaging
– PowerPAD MSOP
– SOIC
Pin Compatible With LM4880 and LM4881
(SOIC)
description
The TPA122 is a stereo audio power amplifier packaged in either an 8-pin SOIC, or an 8-pin PowerPAD MSOP
package capable of delivering 150 mW of continuous RMS power per channel into 8-Ω loads. Amplifier gain
isexternallyconfiguredbymeansoftworesistorsperinputchannelanddoesnotrequireexternalcompensation
for settings of 1 to 10.
THD+N when driving an 8-Ω load from 5 V is 0.1% at 1 kHz, and less than 2% across the audio band of 20 Hz
to 20 kHz. For 32-Ω loads, the THD+N is reduced to less than 0.06% at 1 kHz, and is less than 1% across the
audiobandof20Hzto20kHz. For10-kΩ loads, theTHD+Nperformanceis0.01%at1kHz, andlessthan0.02%
across the audio band of 20 Hz to 20 kHz.
typical application circuit
320 kΩ
320 kΩ
V
8
1
R
DD
F
V
DD
Audio
Input
C
S
V
/2
DD
R
I
IN1–
2
3
V
1
O
O
–
+
C
I
C
C
BYPASS
IN2–
C
Audio
Input
B
R
I
6
5
V
2
7
4
–
+
C
I
C
C
From Shutdown
Control Circuit
SHUTDOWN
Bias
Control
R
F
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.
PowerPAD is a trademark of Texas Instruments.
Copyright 2000, Texas Instruments Incorporated
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
1
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
TPA122
150-mW STEREO AUDIO POWER AMPLIFIER
SLOS211C – AUGUST1998 – REVISED MARCH 2000
AVAILABLE OPTIONS
PACKAGED DEVICES
†
MSOP
Symbolization
†
MSOP
T
A
SMALL OUTLINE
(D)
(DGN)
–40°C to 85°C
TPA122D
TPA122DGN
TI AAE
†
The D and DGN package is available in left-ended tape and reel only (e.g., TPA122DR,
TPA122DGNR).
Terminal Functions
TERMINAL
NAME
BYPASS
I/O
DESCRIPTION
NO.
3
I
Tap to voltage divider for internal mid-supply bias supply. Connect to a 0.1 µF to 1 µF low ESR capacitor for
best performance.
GND
4
2
6
5
8
1
7
I
I
GND is the ground connection.
IN1–
IN1– is the inverting input for channel 1.
IN2– is the inverting input for channel 2.
Puts the device in a low quiescent current mode when held high
IN2–
I
SHUTDOWN
I
V
V
V
I
V
V
V
is the supply voltage terminal.
DD
DD
1
2
O
O
1 is the audio output for channel 1.
2 is the audio output for channel 2.
O
O
O
O
†
absolute maximum ratings over operating free-air temperature (unless otherwise noted)
Supply voltage, V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 V
DD
Input voltage, V . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to V + 0.3 V
I
DD
Continuous total power dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . internally limited
Operating junction temperature range, T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –40°C to 150°C
J
Storage temperature range, T
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –65°C to 150°C
stg
Lead temperature 1,6 mm (1/16 inch) from case for 10 seconds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260°C
†
Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings 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.
DISSIPATION RATING TABLE
T
≤ 25°C
DERATING FACTOR
T
= 70°C
T = 85°C
A
A
A
PACKAGE
POWER RATING
ABOVE T = 25°C
POWER RATING POWER RATING
A
D
725 mW
5.8 mW/°C
464 mW
1.37 W
377 mW
1.11 W
‡
DGN
2.14 W
17.1 mW/°C
‡
Please see the Texas Instruments document, PowerPAD Thermally Enhanced Package Application Report
(literature number 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 InstrumentsRecommended
Board for PowerPAD on page 33 of the before mentioned document.
recommended operating conditions
MIN
2.5
MAX
5.5
UNIT
V
Supply voltage, V
DD
Operating free-air temperature, T
–40
85
°C
A
2
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
TPA122
150-mW STEREO AUDIO POWER AMPLIFIER
SLOS211C – AUGUST1998 – REVISED MARCH 2000
dc electrical characteristics at T = 25°C, V
= 3.3 V
DD
A
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
mV
dB
V
Input offset voltage
5
IO
PSRR
Power supply rejection ratio
Supply current
V
DD
= 3.2 V to 3.4 V
83
1.5
10
I
I
3
mA
µA
DD
Supply current in SHUTDOWN mode
Input impedance
50
DD(SD)
Z
I
>1
MΩ
ac operating characteristics, V
= 3.3 V, T = 25°C, R = 8 Ω
DD
A
L
PARAMETER
Output power (each channel)
Total harmonic distortion + noise
Maximum output power BW
Phase margin
TEST CONDITIONS
MIN
TYP
MAX
UNIT
†
70
P
THD ≤ 0.1%
= 70 mW,
mW
O
THD+N
P
20–20 kHz
THD <5%
2%
>20
58°
68
O
B
OM
G = 10,
kHz
Open loop
f = 1 kHz
f = 1 kHz
Supply ripple rejection
dB
dB
Channel/Channel output separation
Signal-to-noise ratio
86
SNR
P
O
= 100 mW
100
9.5
dB
V
n
Noise output voltage
µV(rms)
†
Measured at 1 kHz
dc electrical characteristics at T = 25°C, V
= 5 V
DD
A
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
mV
dB
V
Input offset voltage
5
IO
PSRR
Power supply rejection ratio
Supply current
V
DD
= 4.9 V to 5.1 V
76
1.5
60
I
I
3
mA
µA
DD
Supply current in SHUTDOWN mode
Input impedance
100
DD(SD)
Z
I
>1
MΩ
ac operating characteristics, V
= 5 V, T = 25°C, R = 8 Ω
A L
DD
PARAMETER
Output power (each channel)
Total harmonic distortion + noise
Maximum output power BW
Phase margin
TEST CONDITIONS
THD ≤ 0.1%
P = 150 mW, 20–20 kHz
O
MIN
TYP
70†
2%
>20
56°
68
MAX
UNIT
P
mW
O
THD+N
B
OM
G = 10,
THD <5%
kHz
Open loop
f = 1 kHz
f = 1 kHz
Supply ripple rejection ratio
dB
dB
Channel/channel output separation
Signal-to-noise ratio
86
SNR
P
O
= 150 mW
100
9.5
dB
V
n
Noise output voltage
µV(rms)
†
Measured at 1 kHz
3
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
TPA122
150-mW STEREO AUDIO POWER AMPLIFIER
SLOS211C – AUGUST1998 – REVISED MARCH 2000
ac operating characteristics, V
= 3.3 V, T = 25°C, R = 32 Ω
DD
A
L
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
†
P
Output power (each channel)
Total harmonic distortion + noise
Maximum output power BW
Phase margin
THD ≤ 0.1%
= 30 mW,
40
mW
O
THD+N
P
O
20–20 kHz
THD <2%
0.5%
>20
58°
68
B
OM
G = 10,
kHz
Open loop
f = 1 kHz
f = 1 kHz
Supply ripple rejection
dB
dB
Channel/channel output separation
Signal-to-noise ratio
86
SNR
P
O
= 100 mW
100
9.5
dB
V
n
Noise output voltage
µV(rms)
†
Measured at 1 kHz
ac operating characteristics, V
= 5 V, T = 25°C, R = 32 Ω
A L
DD
PARAMETER
TEST CONDITIONS
THD ≤ 0.1%
= 60 mW,
MIN
TYP
40†
0.4%
>20
56°
68
MAX
UNIT
P
O
Output power (each channel)
Total harmonic distortion + noise
Maximum output power BW
Phase margin
mW
THD+N
P
O
20–20 kHz
THD <2%
B
OM
G = 10,
kHz
Open loop
f = 1 kHz
f = 1 kHz
Supply ripple rejection
dB
dB
Channel/channel output separation
Signal-to-noise ratio
86
SNR
P
O
= 150 mW
100
9.5
dB
V
n
Noise output voltage
µV(rms)
†
Measured at 1 kHz
4
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
TPA122
150-mW STEREO AUDIO POWER AMPLIFIER
SLOS211C – AUGUST1998 – REVISED MARCH 2000
TYPICAL CHARACTERISTICS
Table of Graphs
FIGURE
1, 2, 4, 5, 7, 8,
10, 11, 13, 14,
16, 17, 34, 36
vs Frequency
THD+N
Total harmonic distortion plus noise
3, 6, 9,
12, 15, 18
vs Power output
Supply ripple rejection
Output noise voltage
vs Frequency
vs Frequency
19, 20
21, 22
V
n
23 – 26,
37, 38
Crosstalk
vs Frequency
Mute attenuation
vs Frequency
27, 28
29, 30
31, 32
39 – 44
31, 32
33
Open-loop gain and phase margin
Output power
vs Frequency
vs Load resistance
vs Frequency
Closed-Loop gain and phase
Output power
vs Load resistance
vs Supply voltage
vs Voltage gain
vs Frequency
I
Supply current
DD
SNR
Signal-to-noise ratio
Closed-loop gain
35
39 – 44
45, 46
Power dissipation/amplifier
vs Output power
5
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
TPA122
150-mW STEREO AUDIO POWER AMPLIFIER
SLOS211C – AUGUST1998 – REVISED MARCH 2000
TYPICAL CHARACTERISTICS
TOTAL HARMONIC DISTORTION PLUS NOISE
TOTAL HARMONIC DISTORTION PLUS NOISE
vs
vs
FREQUENCY
FREQUENCY
10
1
10
1
V
P
C
R
= 3.3 V
DD
O
B
L
V
= 3.3 V
= –1 V/V
= 32 Ω
DD
= 30 mW
= 1 µ F
= 32 Ω
A
V
R
C
L
B
= 1 µ F
A
V
= –5 V/V
A
V
= –10 V/V
P
O
= 15 mW
0.1
0.1
P
O
= 10 mW
A
V
= –1 V/V
0.01
0.01
P
O
= 30 mW
0.001
0.001
20
100
1k
10k 20k
20
100
1k
f – Frequency – Hz
10k 20k
f – Frequency – Hz
Figure 1
Figure 2
TOTAL HARMONIC DISTORTION PLUS NOISE
TOTAL HARMONIC DISTORTION PLUS NOISE
vs
vs
OUTPUT POWER
FREQUENCY
10
10
1
V
= 3.3 V
V
P
R
C
= 5 V
= 60 mW
= 32 Ω
DD
= 32 Ω
DD
O
L
B
R
A
L
= –1 V/V
= 1 µF
V
C
= 1 µF
B
20 kHz
10 kHz
1
A
V
= –10 V/V
A
V
= –5 V/V
0.1
0.1
1 kHz
20 Hz
0.01
A
V
= –1 V/V
0.001
0.01
1
10
– Output Power – mW
50
20
100
1k
f – Frequency – Hz
10k 20k
P
O
Figure 3
Figure 4
6
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
TPA122
150-mW STEREO AUDIO POWER AMPLIFIER
SLOS211C – AUGUST1998 – REVISED MARCH 2000
TYPICAL CHARACTERISTICS
TOTAL HARMONIC DISTORTION PLUS NOISE
TOTAL HARMONIC DISTORTION PLUS NOISE
vs
vs
FREQUENCY
OUTPUT POWER
10
10
1
V
= 5 V
= 32 Ω
= –1 V/V
= 1 µF
V
= 5 V
= –1 V/V
= 32 Ω
= 1 µF
DD
L
DD
R
A
A
V
R
C
V
L
B
C
B
20 kHz
10 kHz
1
P
O
= 30 mW
0.1
P
O
= 15 mW
0.1
1 kHz
0.01
20 Hz
P
O
= 60 mW
0.001
0.01
20
100
1k
10k 20k
0.002
0.01
– Output Power – W
0.1
0.2
P
O
f – Frequency – Hz
Figure 5
Figure 6
TOTAL HARMONIC DISTORTION PLUS NOISE
TOTAL HARMONIC DISTORTION PLUS NOISE
vs
vs
FREQUENCY
FREQUENCY
10
1
10
1
V
R
= 3.3 V
= 10 kΩ
= 100 µF
= 1 µF
DD
L
V
= 3.3 V
= 10 kΩ
= –1 V/V
= 1 µF
DD
R
L
P
C
O
A
V
B
C
B
A
V
= –5 V/V
0.1
0.1
P
O
= 45 µW
0.01
0.01
A
V
= –2 V/V
P
O
= 90 µW
P
O
= 130 µW
0.001
0.001
20
100
1k
10k 20k
20
100
1k
f – Frequency – Hz
Figure 8
10k 20k
f – Frequency – Hz
Figure 7
7
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
TPA122
150-mW STEREO AUDIO POWER AMPLIFIER
SLOS211C – AUGUST1998 – REVISED MARCH 2000
TYPICAL CHARACTERISTICS
TOTAL HARMONIC DISTORTION PLUS NOISE
TOTAL HARMONIC DISTORTION PLUS NOISE
vs
vs
OUTPUT POWER
FREQUENCY
10
1
10
1
V
= 3.3 V
= 10 kΩ
= –1 V/V
= 1 µF
DD
L
V
= 5 V
R
A
DD
L
R
P
= 10 kΩ
= 300 µW
= 1 µF
V
C
B
O
C
B
0.1
0.1
A
V
= –5 V/V
20 Hz
10 kHz
A
V
= –1 V/V
0.01
0.01
20 Hz
1 kHz
A
V
= –2 V/V
0.001
0.001
5
10
100
200
20
100
1k
10k 20k
P
O
– Output Power – µW
f – Frequency – Hz
Figure 9
Figure 10
TOTAL HARMONIC DISTORTION PLUS NOISE
TOTAL HARMONIC DISTORTION PLUS NOISE
vs
vs
FREQUENCY
OUTPUT POWER
10
10
1
V
R
= 5 V
= 10 kΩ
= –1 V/V
= 1 µF
DD
L
V
= 5 V
= 10 kΩ
= –1 V/V
= 1 µ F
DD
R
L
A
V
A
V
C
B
C
B
1
P
O
= 300 µW
0.1
0.1
P
O
= 200 µW
20 Hz
20 kHz
0.01
0.01
10 kHz
100
P
O
= 100 µW
1 kHz
0.001
0.001
20
100
1k
10k 20k
5
10
500
f – Frequency – Hz
P
O
– Output Power – µW
Figure 11
Figure 12
8
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
TPA122
150-mW STEREO AUDIO POWER AMPLIFIER
SLOS211C – AUGUST1998 – REVISED MARCH 2000
TYPICAL CHARACTERISTICS
TOTAL HARMONIC DISTORTION PLUS NOISE
TOTAL HARMONIC DISTORTION PLUS NOISE
vs
vs
FREQUENCY
FREQUENCY
2
1
10
1
V
= 3.3 V
= 75 mW
= 8 Ω
DD
V
R
A
V
= 3.3 V
DD
= 8 Ω
P
R
C
O
L
A
V
= –5 V/V
L
= –1 V/V
= 1 µF
B
P
O
= 30 mW
A
V
= –2 V/V
0.1
P
O
= 15 mW
A
V
= –1 V/V
0.1
0.01
0.01
P
O
= 75 mW
1k
0.001
0.001
20
100
1k
f – Frequency – Hz
10k 20k
20
100
10k 20k
f – Frequency – Hz
Figure 13
Figure 14
TOTAL HARMONIC DISTORTION PLUS NOISE
TOTAL HARMONIC DISTORTION PLUS NOISE
vs
vs
OUTPUT POWER
FREQUENCY
2
1
10
V
R
A
V
= 3.3 V
= 8 Ω
= –1 V/V
DD
L
V
= 5 V
= 100 mW
= 8 Ω
A
= –2 V/V
DD
V
P
R
C
O
A = –5 V/V
V
20 kHz
10 kHz
L
= 1 µF
B
1
0.1
A
V
= –1 V/V
1 kHz
0.1
0.01
20 Hz
0.001
0.01
20
100
1k
f – Frequency – Hz
10k 20k
10m
0.1
– Output Power – W
0.3
P
O
Figure 15
Figure 16
9
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
TPA122
150-mW STEREO AUDIO POWER AMPLIFIER
SLOS211C – AUGUST1998 – REVISED MARCH 2000
TYPICAL CHARACTERISTICS
TOTAL HARMONIC DISTORTION PLUS NOISE
TOTAL HARMONIC DISTORTION PLUS NOISE
vs
vs
FREQUENCY
POWER OUTPUT
10
1
10
V
= 5 V
= 8 Ω
= –1 V/V
V
= 5 V
= 8 Ω
= –1 V/V
DD
L
DD
L
R
A
R
A
V
V
20 kHz
P
O
= 30 mW
1
0.1
P
O
= 60 mW
10 kHz
1 kHz
0.1
0.01
20 Hz
P
O
= 10 mW
1k
0.001
0.01
20
100
10k 20k
10m
0.1
1
f – Frequency – Hz
P
O
– Output Power – W
Figure 17
Figure 18
SUPPLY RIPPLE REJECTION RATIO
SUPPLY RIPPLE REJECTION RATIO
vs
vs
FREQUENCY
FREQUENCY
0
–10
–20
–30
0
–10
–20
–30
V
R
= 3.3 V
= 8 Ω to 10 kΩ
DD
L
V
R
= 5 V
= 8 Ω to 10 kΩ
DD
L
C
= 0.1 µF
B
C = 0.1 µF
B
C
= 1 µF
B
C = 1 µF
B
–40
–50
–60
–40
–50
–60
C
= 2 µF
B
C = 2 µF
B
–70
–80
–90
Bypass = 1.65 V
–70
–80
–90
Bypass = 2.5 V
–100
20
–100
100
1k
10k 20k
20
100
1k
10k 20k
f – Frequency – Hz
f – Frequency – Hz
Figure 19
Figure 20
10
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
TPA122
150-mW STEREO AUDIO POWER AMPLIFIER
SLOS211C – AUGUST1998 – REVISED MARCH 2000
TYPICAL CHARACTERISTICS
OUTPUT NOISE VOLTAGE
OUTPUT NOISE VOLTAGE
vs
vs
FREQUENCY
FREQUENCY
20
10
20
10
V
= 3.3 V
DD
BW = 10 Hz to 22 kHz
V
= 5 V
DD
BW = 10 Hz to 22 kHz
A
= –1 V/V
= 8 Ω to 10 kΩ
V
R
A
V
= 8 Ω to 10 kΩ
= –1 V/V
L
R
L
1
1
20
20
100
1k
10k 20k
100
1k
10k 20k
f – Frequency – Hz
f – Frequency – Hz
Figure 21
Figure 22
CROSSTALK
vs
FREQUENCY
CROSSTALK
vs
FREQUENCY
–60
–50
–55
–60
–65
P
V
R
C
= 25 mW
= 3.3 V
= 32 Ω
= 1 µF
O
DD
L
B
P
V
R
C
= 100 mW
O
–65
–70
–75
= 3.3 V
= 8 Ω
DD
L
B
= 1 µF
= –1 V/V
A
V
= –1 V/V
A
V
–80
–85
–90
–70
–75
–80
IN 2 TO OUT 1
IN 2 TO OUT 1
–95
–100
–105
–85
–90
–95
IN 1 TO OUT 2
IN 1 TO OUT 2
–110
–100
20
100
1k
10k 20k
20
100
1k
10k 20k
f – Frequency – Hz
f – Frequency – Hz
Figure 23
Figure 24
11
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
TPA122
150-mW STEREO AUDIO POWER AMPLIFIER
SLOS211C – AUGUST1998 – REVISED MARCH 2000
TYPICAL CHARACTERISTICS
CROSSTALK
vs
FREQUENCY
CROSSTALK
vs
FREQUENCY
–60
–65
–65
–50
–55
–60
V
= 5 V
= 25 mW
= 1 µF
= 32 Ω
= –1 V/V
V
P
= 5 V
= 100 mW
= 1 µF
= 8 Ω
= –1 V/V
DD
DD
O
B
L
P
O
C
R
A
C
R
A
B
L
V
V
–75
–80
–65
–70
IN 2 TO OUT 1
–85
–90
–95
–75
–80
–85
IN 2 TO OUT 1
–100
–105
–110
–90
–95
IN 1 TO OUT 2
IN 1 TO OUT 2
–100
20
100
1k
10k
20k
20
100
1k
10k
20k
f – Frequency – Hz
f – Frequency – Hz
Figure 25
Figure 26
MUTE ATTENUATION
vs
MUTE ATTENUATION
vs
FREQUENCY
FREQUENCY
0
–10
–20
–30
0
–10
–20
V
R
C
= 3.3 V
= 32 Ω
= 1 µF
DD
L
B
V
C
R
= 5 V
= 1 µF
= 32 Ω
DD
B
L
–30
–40
–40
–50
–60
–50
–60
–70
–70
–80
–90
–80
–90
–100
–100
20
100
1k
10k 20k
20
100
1k
10k
20k
f – Frequency – Hz
f – Frequency – Hz
Figure 27
Figure 28
12
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
TPA122
150-mW STEREO AUDIO POWER AMPLIFIER
SLOS211C – AUGUST1998 – REVISED MARCH 2000
TYPICAL CHARACTERISTICS
OPEN-LOOP GAIN AND PHASE MARGIN
vs
FREQUENCY
150°
120°
100
80
60
40
20
V
= 3.3 V
DD
= 25°C
T
A
No Load
Phase
90°
60°
30°
0°
Gain
0
–20
–30°
10
100
1k
10k
100k
10M
f – Frequency – Hz
Figure 29
OPEN-LOOP GAIN AND PHASE MARGIN
vs
FREQUENCY
100
150°
120°
V
= 5 V
DD
= 25°C
T
A
No Load
80
60
40
20
Phase
90°
60°
30°
0°
Gain
0
–20
–30°
10M
100
1k
10k
100k
1M
f – Frequency – Hz
Figure 30
13
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
TPA122
150-mW STEREO AUDIO POWER AMPLIFIER
SLOS211C – AUGUST1998 – REVISED MARCH 2000
TYPICAL CHARACTERISTICS
OUTPUT POWER
vs
LOAD RESISTANCE
OUTPUT POWER
vs
LOAD RESISTANCE
120
100
300
250
THD+N = 1 %
THD+N = 1 %
V
A
= 3.3 V
= –1 V/V
DD
V
A
= 5 V
= –1 V/V
DD
V
V
80
60
40
200
150
100
20
0
50
0
8
16
24
32
40
48
56
64
8
16
24
32
40
48
56
64
R
– Load Resistance – Ω
L
R
– Load Resistance – Ω
L
Figure 31
Figure 32
SUPPLY CURRENT
vs
SUPPLY VOLTAGE
TOTAL HARMONIC DISTORTION PLUS NOISE
vs
FREQUENCY
1
1.4
V = 1 V
I
A
R
= –1 V/V
= 10 kΩ
= 1 µF
V
1.2
1
L
B
C
0.1
0.01
0.8
0.6
0.4
0.2
0
0.001
20
100
1k
10k 20k
2.5
3
3.5
4
4.5
5
5.5
f – Frequency – Hz
V
DD
– Supply Voltage – V
Figure 33
Figure 34
14
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
TPA122
150-mW STEREO AUDIO POWER AMPLIFIER
SLOS211C – AUGUST1998 – REVISED MARCH 2000
TYPICAL CHARACTERISTICS
SIGNAL-TO-NOISE RATIO
TOTAL HARMONIC DISTORTION PLUS NOISE
vs
vs
VOLTAGE GAIN
FREQUENCY
104
102
1
V = 1 V
I
V
= 5 V
DD
A
= –1 V/V
= 10 kΩ
= 1 µF
V
R
C
L
B
100
98
0.1
96
94
0.01
0.001
92
1
2
3
4
5
6
7
8
9
10
20
100
1k
10k 20k
A
V
– Voltage Gain – V/V
f – Frequency – Hz
Figure 35
Figure 36
CROSSTALK
vs
FREQUENCY
CROSSTALK
vs
FREQUENCY
–60
–70
–60
–70
V
V
R
C
= 5 V
= 1 V
= 10 kΩ
= 1 µF
DD
O
L
B
V
V
R
C
= 3.3 V
= 1 V
= 10 kΩ
= 1 µF
DD
O
L
B
–80
–90
–80
–90
–100
–110
–120
–130
–140
–150
–100
–110
–120
–130
–140
–150
IN2 to OUT1
IN2 to OUT1
IN1 to OUT2
IN1 to OUT2
100
20
100
1k
10k 20k
20
1k
10k 20k
f – Frequency – Hz
f – Frequency – Hz
Figure 37
Figure 38
15
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
TPA122
150-mW STEREO AUDIO POWER AMPLIFIER
SLOS211C – AUGUST1998 – REVISED MARCH 2000
TYPICAL CHARACTERISTICS
CLOSED-LOOP GAIN AND PHASE
vs
FREQUENCY
200°
180°
160°
140°
120°
Phase
V
= 3.3 V
DD
R = 20 kΩ
100°
80°
I
R
R
= 20 kΩ
= 32 Ω
F
L
I
C = 1 µF
A
V
30
20
= –1 V/V
10
0
Gain
–10
10
100
1k
10k
100k
1M
f – Frequency – Hz
Figure 39
CLOSED-LOOP GAIN AND PHASE
vs
FREQUENCY
200°
180°
160°
140°
120°
Phase
V
= 5 V
DD
R = 20 kΩ
100°
80°
I
R
R
= 20 kΩ
= 32 Ω
F
L
I
C = 1 µF
A
V
30
20
= –1 V/V
10
0
Gain
–10
10
100
1k
10k
100k
1M
f – Frequency – Hz
Figure 40
16
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
TPA122
150-mW STEREO AUDIO POWER AMPLIFIER
SLOS211C – AUGUST1998 – REVISED MARCH 2000
TYPICAL CHARACTERISTICS
CLOSED-LOOP GAIN AND PHASE
vs
FREQUENCY
200°
180°
160°
140°
120°
Phase
V
= 3.3 V
DD
R = 20 kΩ
100°
80°
I
R
R
= 20 kΩ
= 8 Ω
F
L
I
C = 1 µF
A
V
60°
= –1 V/V
40
Gain
20
0
–20
10
100
1k
10k
100k
1M
f – Frequency – Hz
Figure 41
CLOSED-LOOP GAIN AND PHASE
vs
FREQUENCY
200°
180°
160°
140°
120°
Phase
V
= 3.3 V
DD
R = 20 kΩ
100°
80°
I
R
R
= 20 kΩ
= 10 kΩ
F
L
I
C = 1 µF
A
V
30
20
= –1 V/V
10
0
Gain
–10
10
100
1k
10k
100k
1M
f – Frequency – Hz
Figure 42
17
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
TPA122
150-mW STEREO AUDIO POWER AMPLIFIER
SLOS211C – AUGUST1998 – REVISED MARCH 2000
TYPICAL CHARACTERISTICS
CLOSED-LOOP GAIN AND PHASE
vs
FREQUENCY
200°
180°
160°
140°
120°
Phase
V
= 5 V
DD
R = 20 kΩ
I
R
R
= 20 kΩ
= 8 Ω
F
L
I
100°
80°
C = 1 µF
A
V
= –1 V/V
60°
40°
Gain
20
0
–20
10
100
1k
10k
100k
1M
f – Frequency – Hz
Figure 43
CLOSED-LOOP GAIN AND PHASE
vs
FREQUENCY
200°
180°
160°
140°
120°
Phase
V
= 5 V
DD
R = 20 kΩ
I
100°
80°
R
R
= 20 kΩ
= 10 kΩ
F
L
I
C = 1 µF
A
V
30
20
= –1 V/V
10
0
Gain
10k
–10
10
100
1k
100k
1M
f – Frequency – Hz
Figure 44
18
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
TPA122
150-mW STEREO AUDIO POWER AMPLIFIER
SLOS211C – AUGUST1998 – REVISED MARCH 2000
TYPICAL CHARACTERISTICS
POWER DISSIPATION/AMPLIFIER
POWER DISSIPATION/AMPLIFIER
vs
vs
OUTPUT POWER
OUTPUT POWER
80
70
60
50
180
160
V
= 3.3 V
V
= 5 V
DD
DD
8 Ω
8 Ω
140
120
100
80
40
30
20
10
16 Ω
16 Ω
60
32 Ω
64 Ω
40
32 Ω
64 Ω
20
0
0
0
20 40 60 80 100 120 140
Load Power – mW
180 200
160
0
20 40 60 80 100 120 140
Load Power – mW
180 200
160
Figure 45
Figure 46
APPLICATION INFORMATION
gain setting resistors, R and R
F
I
The gain for the TPA122 is set by resistors R and R according to equation 1.
F
I
R
F
Gain
(1)
R
I
Given that the TPA122 is a MOS amplifier, the input impedance is very high. Consequently input leakage
currents are not generally a concern, although noise in the circuit increases as the value of R increases. In
F
addition, a certain range of R values is required for proper start-up operation of the amplifier. Taken together
F
it is recommended that the effective impedance seen by the inverting node of the amplifier be set between
5 kΩ and 20 kΩ. The effective impedance is calculated in equation 2.
R R
F I
Effective Impedance
(2)
R
R
F
I
As an example, consider an input resistance of 20 kΩ and a feedback resistor of 20 kΩ. The gain of the amplifier
would be –1 and the effective impedance at the inverting terminal would be 10 kΩ, which is within the
recommended range.
19
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
TPA122
150-mW STEREO AUDIO POWER AMPLIFIER
SLOS211C – AUGUST1998 – REVISED MARCH 2000
APPLICATION INFORMATION
gain setting resistors, R and R (continued)
F
I
For high performance applications, metal film resistors are recommended because they tend to have lower
noise levels than carbon resistors. For values of R above 50 kΩ, the amplifier tends to become unstable due
F
to a pole formed from R and the inherent input capacitance of the MOS input structure. For this reason, a small
F
compensation capacitor of approximately 5 pF should be placed in parallel with R . This, in effect, creates a
F
low-pass filter network with the cutoff frequency defined in equation 3.
1
2 R C
f
(3)
c(lowpass)
F
F
For example, if R is 100 kΩ and C is 5 pF then f is 318 kHz, which is well outside the audio range.
c(lowpass)
F
F
input capacitor, C
I
In the typical application, an input capacitor, C , is required to allow the amplifier to bias the input signal to the
I
proper dc level for optimum operation. In this case, C and R form a high-pass filter with the corner frequency
I
I
determined in equation 4.
1
f
(4)
c(highpass)
2 R C
I
I
The value of C is important to consider, as it directly affects the bass (low frequency) performance of the circuit.
I
Consider the example where R is 20 kΩ and the specification calls for a flat bass response down to 20 Hz.
I
Equation 4 is reconfigured as equation 5.
1
C
(5)
I
2 R f
c(highpass)
I
In this example, C is 0.40 µF, so one would likely choose a value in the range of 0.47 µF to 1 µF. A further
I
consideration for this capacitor is the leakage path from the input source through the input network (R , C ) and
I
I
thefeedbackresistor(R )totheload. Thisleakagecurrentcreatesadcoffsetvoltageattheinputtotheamplifier
F
that reduces useful headroom, especially in high-gain applications (> 10). For this reason a low-leakage
tantalum or ceramic capacitor is the best choice. When polarized capacitors are used, the positive side of the
capacitor should face the amplifier input in most applications, as the dc level there is held at V /2, which is
DD
likely higher than the source dc level. Please note that it is important to confirm the capacitor polarity in the
application.
power supply decoupling, C
S
The TPA122 is a high-performance CMOS audio amplifier that requires adequate power supply decoupling to
ensure that the output total harmonic distortion (THD) is as low as possible. Power supply decoupling also
prevents oscillations for long lead lengths between the amplifier and the speaker. The optimum decoupling is
achieved by using two capacitors of different types that target different types of noise on the power supply leads.
For higher frequency transients, spikes, or digital hash on the line, a good low equivalent-series-resistance
(ESR) ceramic capacitor, typically 0.1 µF, placed as close as possible to the device V
filtering lower-frequency noise signals, a larger aluminum electrolytic capacitor of 10 µF or greater placed near
lead, works best. For
DD
the power amplifier is recommended.
20
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
TPA122
150-mW STEREO AUDIO POWER AMPLIFIER
SLOS211C – AUGUST1998 – REVISED MARCH 2000
APPLICATION INFORMATION
midrail bypass capacitor, C
B
The midrail bypass capacitor, C , serves several important functions. During start-up, C determines the rate
B
B
at which the amplifier starts up. This helps to push the start-up pop noise into the subaudible range (so low it
can not be heard). The second function is to reduce noise produced by the power supply caused by coupling
intotheoutputdrivesignal. Thisnoiseisfromthemidrailgenerationcircuitinternaltotheamplifier. Thecapacitor
is fed from a 160-kΩ source inside the amplifier. To keep the start-up pop as low as possible, the relationship
shown in equation 6 should be maintained.
1
1
(6)
C
160 kΩ
C R
I
B
I
As an example, consider a circuit where C is 1 µF, C is 1 µF, and R is 20 kΩ. Inserting these values into the
B
I
I
equation 9 results in: 6.25 ≤ 50 which satisfies the rule. Bypass capacitor, C , values of 0.1 µF to 1 µF ceramic
B
or tantalum low-ESR capacitors are recommended for the best THD and noise performance.
output coupling capacitor, C
C
In the typical single-supply single-ended (SE) configuration, an output coupling capacitor (C ) is required to
C
block the dc bias at the output of the amplifier, thus preventing dc currents in the load. As with the input coupling
capacitor, the output coupling capacitor and impedance of the load form a high-pass filter governed by
equation 7.
1
f
c
(7)
2 R C
L
C
The main disadvantage, from a performance standpoint, is that the typically small load impedances drive the
low-frequency corner higher. Large values of C are required to pass low frequencies into the load. Consider
C
the example where a C of 68 µF is chosen and loads vary from 32 Ω to 47 kΩ. Table 1 summarizes the
C
frequency response characteristics of each configuration.
Table 1. Common Load Impedances vs Low Frequency Output Characteristics in SE Mode
R
C
LOWEST FREQUENCY
L
C
32 Ω
10,000 Ω
47,000 Ω
68 µF
68 µF
68 µF
73 Hz
0.23 Hz
0.05 Hz
As Table 1 indicates, headphone response is adequate and drive into line level inputs (a home stereo for
example) is very good.
The output coupling capacitor required in single-supply SE mode also places additional constraints on the
selection of other components in the amplifier circuit. With the rules described earlier still valid, add the following
relationship:
(8)
1
1
1
R C
C
160 kΩ
C R
I
L C
B
I
21
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
TPA122
150-mW STEREO AUDIO POWER AMPLIFIER
SLOS211C – AUGUST1998 – REVISED MARCH 2000
APPLICATION INFORMATION
using low-ESR capacitors
Low-ESR capacitors are recommended throughout this application. A real capacitor can be modeled simply as
a resistor in series with an ideal capacitor. The voltage drop across this resistor minimizes the beneficial effects
of the capacitor in the circuit. The lower the equivalent value of this resistance, the more the real capacitor
behaves like an ideal capacitor.
5-V versus 3.3-V operation
The TPA122 was designed for operation over a supply range of 2.7 V to 5.5 V. This data sheet provides full
specifications for 5-V and 3.3-V operation since these are considered to be the two most common standard
voltages. There are no special considerations for 3.3-V versus 5-V operation as far as supply bypassing, gain
setting, or stability. Supply current is slightly reduced from 3.5 mA (typical) to 2.5 mA (typical). The most
important consideration is that of output power. Each amplifier in the TPA122 can produce a maximum voltage
swing ofV
– 1 V. This means, for 3.3-V operation, clipping starts to occur when V
= 4 V while operating at 5 V. The reduced voltage swing subsequently reduces maximum output
= 2.3 V as opposed
DD
O(PP)
when V
O(PP)
power into the load before distortion begins to become significant.
22
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
TPA122
150-mW STEREO AUDIO POWER AMPLIFIER
SLOS211C – AUGUST1998 – REVISED MARCH 2000
MECHANICAL DATA
D (R-PDSO-G**)
PLASTIC SMALL-OUTLINE PACKAGE
14 PINS SHOWN
0.050 (1,27)
0.020 (0,51)
0.014 (0,35)
0.010 (0,25)
M
14
8
0.008 (0,20) NOM
0.244 (6,20)
0.228 (5,80)
0.157 (4,00)
0.150 (3,81)
Gage Plane
0.010 (0,25)
1
7
0°–8°
0.044 (1,12)
A
0.016 (0,40)
Seating Plane
0.004 (0,10)
0.010 (0,25)
0.004 (0,10)
0.069 (1,75) MAX
PINS **
8
14
16
DIM
0.197
(5,00)
0.344
(8,75)
0.394
(10,00)
A MAX
0.189
(4,80)
0.337
(8,55)
0.386
(9,80)
A MIN
4040047/D 10/96
NOTES: A. All linear dimensions are in inches (millimeters).
B. This drawing is subject to change without notice.
C. Body dimensions do not include mold flash or protrusion, not to exceed 0.006 (0,15).
D. Falls within JEDEC MS-012
23
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
TPA122
150-mW STEREO AUDIO POWER AMPLIFIER
SLOS211C – AUGUST1998 – REVISED MARCH 2000
MECHANICAL DATA
DGN (S-PDSO-G8)
PowerPAD PLASTIC SMALL-OUTLINE PACKAGE
0,38
0,25
0,65
M
0,25
8
5
Thermal Pad
(See Note D)
0,15 NOM
3,05
2,95
4,98
4,78
Gage Plane
0,25
0°–6°
1
4
0,69
0,41
3,05
2,95
Seating Plane
0,10
0,15
0,05
1,07 MAX
4073271/A 04/98
NOTES: A. All linear dimensions are in millimeters.
B. This drawing is subject to change without notice.
C. Body dimensions include mold flash or protrusions.
D. The package thermal performance may be enhanced by attaching an external heat sink to the thermal pad.
This pad is electrically and thermally connected to the backside of the die and possibly selected leads.
E. Falls within JEDEC MO-187
PowerPAD is a trademark of Texas Instruments.
24
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
IMPORTANT NOTICE
Texas Instruments and its subsidiaries (TI) reserve the right to make changes to their products or to discontinue
any product or service without notice, and advise customers to obtain the latest version of relevant information
to verify, before placing orders, that information being relied on is current and complete. All products are sold
subject to the terms and conditions of sale supplied at the time of order acknowledgment, including those
pertaining to warranty, patent infringement, and limitation of liability.
TI warrants performance of its semiconductor products to the specifications applicable at the time of sale in
accordance with TI’s standard warranty. Testing and other quality control techniques are utilized to the extent
TI deems necessary to support this warranty. Specific testing of all parameters of each device is not necessarily
performed, except those mandated by government requirements.
Customers are responsible for their applications using TI components.
In order to minimize risks associated with the customer’s applications, adequate design and operating
safeguards must be provided by the customer to minimize inherent or procedural hazards.
TI assumes no liability for applications assistance or customer product design. TI does not warrant or represent
that any license, either express or implied, is granted under any patent right, copyright, mask work right, or other
intellectual property right of TI covering or relating to any combination, machine, or process in which such
semiconductor products or services might be or are used. TI’s publication of information regarding any third
party’s products or services does not constitute TI’s approval, warranty or endorsement thereof.
Copyright 2000, Texas Instruments Incorporated
相关型号：
©2020 ICPDF网 联系我们和版权申明