TI TPA122DGNRG4

TPA122
www.ti.com
SLOS211E – AUGUST 1998 – REVISED JUNE 2004
150-mW STEREO AUDIO POWER AMPLIFIER
FEATURES
•
•
•
•
•
•
•
DESCRIPTION
150-mW Stereo Output
PC Power Supply Compatible
– Fully Specified for 3.3-V and 5-V Operation
– Operation to 2.5 V
Pop Reduction Circuitry
Internal Midrail Generation
Thermal and Short-Circuit Protection
Surface-Mount Packaging
– PowerPAD™ MSOP
– SOIC
Pin Compatible With LM4880 and LM4881
(SOIC)
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 is externally configured by
means of two resistors per input channel and does
not require external compensation 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 audio band of 20 Hz to 20 kHz. For 10-kΩ
loads, the THD+N performance is 0.01% at 1 kHz,
and less than 0.02% across the audio band of 20 Hz
to 20 kHz.
D OR DGN PACKAGE
(TOP VIEW)
VO1
IN1−
BYPASS
GND
1
8
2
7
3
6
4
5
VDD
VO2
IN2−
SHUTDOWN
TYPICAL APPLICATION CIRCUIT
320 kΩ
RF
Audio
Input
320 kΩ
VDD 8
VDD
CS
VDD/2
RI
2
IN1–
3
BYPASS
6
IN2–
CI
VO1 1
–
+
CC
CB
Audio
Input
RI
CI
From Shutdown
Control Circuit
5
VO2 7
–
+
SHUTDOWN
CC
Bias
Control
4
RF
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.
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.
Copyright © 1998–2004, Texas Instruments Incorporated
TPA122
www.ti.com
SLOS211E – AUGUST 1998 – 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
TA
SMALL OUTLINE (1)
(D)
MSOP (1)
(DGN)
–40°C to 85°C
TPA122D
TPA122DGN
(1)
MSOP
SYMBOLIZATION
TI AAE
The D and DGN packages are available in left-ended tape and reel only (e.g., TPA122DR,
TPA122DGNR).
Terminal Functions
TERMINAL
NAME
I/O
NO.
DESCRIPTION
BYPASS
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
I
GND is the ground connection.
IN1-
2
I
IN1- is the inverting input for channel 1.
IN2-
6
I
IN2- is the inverting input for channel 2.
SHUTDOWN
5
I
Puts the device in a low quiescent current mode when held high
VDD
8
I
VDD is the supply voltage terminal.
VO1
1
O
VO1 is the audio output for channel 1.
VO2
7
O
VO2 is the audio output for channel 2.
ABSOLUTE MAXIMUM RATINGS
over operating free-air temperature range (unless otherwise noted) (1)
UNIT
VDD
Supply voltage
VI
Input voltage
6V
–0.3 V to VDD + 0.3 V
Continuous total power dissipation
Internally limited
TJ
Operating junction temperature range
–40°C to 150°C
Tstg
Storage temperature range
–65°C to 150°C
Lead temperature 1,6 mm (1/16 inch) from case for 10 seconds
(1)
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
PACKAGE
(1)
2
TA ≤ 25°C
POWER RATING
DERATING FACTOR
ABOVE TA = 25°C
TA = 70°C
POWER RATING
TA = 85°C
POWER RATING
D
725 mW
5.8 mW/°C
464 mW
377 mW
DGN
2.14 W (1)
17.1 mW/°C
1.37 W
1.11 W
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.
TPA122
www.ti.com
SLOS211E – AUGUST 1998 – REVISED JUNE 2004
RECOMMENDED OPERATING CONDITIONS
MIN
MAX
VDD
Supply voltage
2.5
5.5
V
TA
Operating free-air temperature
–40
85
°C
VIH
High-level input voltage, (SHUTDOWN)
VIL
Low-level input voltage, (SHUTDOWN)
0.80 × VDD
UNIT
V
0.40 × VDD
V
DC ELECTRICAL CHARACTERISTICS
at TA = 25°C, VDD = 3.3 V (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
VOO
Output offset voltage
PSRR
Power supply rejection ratio
VDD = 3.2 V to 3.4 V
83
IDD
Supply current
VDD = 2.5, SHUTDOWN = 0 V
IDD(SD)
Supply current in SHUTDOWN mode
VDD = 2.5, SHUTDOWN = VDD
ZI
Input impedance
MAX
UNIT
10
mV
1.5
3
mA
10
50
µA
dB
>1
MΩ
AC OPERATING CHARACTERISTICS
VDD = 3.3 V, TA = 25°C, RL = 8 Ω
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
70 (1)
UNIT
PO
Output power (each channel)
THD≤ 0.1%
THD+N
Total harmonic distortion + noise
PO = 70 mW, 20 Hz–20 kHz
BOM
Maximum output power BW
G = 10, THD < 5%
Phase margin
Open loop
58°
Supply ripple rejection
f = 1 kHz
68
dB
86
dB
Channel/channel output separation
f = 1 kHz
SNR
Signal-to-noise ratio
PO = 100 mW
Vn
Noise output voltage
(1)
mW
2%
> 20
kHz
100
dB
9.5
µV(rms)
Measured at 1 kHz
DC ELECTRICAL CHARACTERISTICS
at TA = 25°C, VDD = 5.5 V (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
VOO
Output offset voltage
PSRR
Power supply rejection ratio
VDD = 4.9 V to 5.1 V
76
IDD
Supply current
SHUTDOWN = 0 V
IDD(SD)
Supply current in SHUTDOWN mode
SHUTDOWN = VDD
|IIH|
High-level input current (SHUTDOWN)
|IIL|
Low-level input current (SHUTDOWN)
ZI
Input impedance
MAX
UNIT
10
mV
1.5
3
mA
60
100
µA
VDD = 5.5 V, VI = VDD
1
µA
VDD = 5.5 V, VI = 0 V
1
>1
dB
µA
MΩ
3
TPA122
www.ti.com
SLOS211E – AUGUST 1998 – REVISED JUNE 2004
AC OPERATING CHARACTERISTICS
VDD = 5 V, TA = 25°C, RL = 8 Ω
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
70 (1)
UNIT
PO
Output power (each channel)
THD≤ 0.1%
THD+N
Total harmonic distortion + noise
PO = 150 mW, 20 Hz–20 kHz
BOM
Maximum output power BW
G = 10, THD < 5%
Phase margin
Open loop
56°
Supply ripple rejection ratio
f = 1 kHz
68
dB
86
dB
Channel/channel output separation
f = 1 kHz
SNR
Signal-to-noise ratio
PO = 150 mW
Vn
Noise output voltage
(1)
mW
2%
> 20
kHz
100
dB
9.5
µV(rms)
Measured at 1 kHz
AC OPERATING CHARACTERISTICS
VDD = 3.3 V, TA = 25°C, RL = 32 Ω
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
PO
Output power (each channel)
THD≤ 0.1%
40 (1)
THD+N
Total harmonic distortion + noise
PO = 30 mW, 20 Hz–20 kHz
0.5%
BOM
Maximum output power BW
G = 10, THD < 2%
> 20
Phase margin
Open loop
58°
Supply ripple rejection
f = 1 kHz
68
dB
Channel/channel output separation
f = 1 kHz
86
dB
SNR
Signal-to-noise ratio
PO = 100 mW
100
dB
Vn
Noise output voltage
9.5
µV(rms)
(1)
mW
kHz
Measured at 1 kHz
AC OPERATING CHARACTERISTICS
VDD = 5 V, TA = 25°C, RL = 32 Ω
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
PO
Output power (each channel)
THD≤ 0.1%
40 (1)
THD+N
Total harmonic distortion + noise
PO = 60 mW, 20 Hz–20 kHz
0.4%
BOM
Maximum output power BW
G = 10, THD < 2%
> 20
Phase margin
Open loop
56°
Supply ripple rejection
f = 1 kHz
68
dB
Channel/channel output separation
f = 1 kHz
86
dB
SNR
Signal-to-noise ratio
PO = 150 mW
Vn
Noise output voltage
(1)
4
Measured at 1 kHz
mW
kHz
100
dB
9.5
µV(rms)
TPA122
www.ti.com
SLOS211E – AUGUST 1998 – REVISED JUNE 2004
TYPICAL CHARACTERISTICS
Table of Graphs
FIGURE
THD+N
1, 2, 4, 5, 7, 8, 10, 11, 13,
14, 16, 17, 34, 36
vs Frequency
Total harmonic distortion plus noise
vs Output power
3, 6, 9, 12, 15, 18
Supply ripple rejection
vs Frequency
Output noise voltage
vs Frequency
21, 22
Crosstalk
vs Frequency
23-26, 37, 38
Mute attenuation
vs Frequency
27, 28
Open-loop gain and phase margin
vs Frequency
29, 30
Output power
vs Load resistance
31, 32
Phase
vs Frequency
39-44
IDD
Supply current
vs Supply voltage
SNR
Signal-to-noise ratio
vs Voltage gain
Closed-loop gain
vs Frequency
39-44
Power dissipation/amplifier
vs Output power
45, 46
Vn
19, 20
33
35
TOTAL HARMONIC DISTORTION + NOISE
vs
FREQUENCY
TOTAL HARMONIC DISTORTION + NOISE
vs
FREQUENCY
1
10
VDD = 3.3 V
PO = 30 mW
CB = 1 µ F
RL = 32 Ω
AV = −5 V/V
AV = −10 V/V
0.1
AV = −1 V/V
0.01
0.001
20
100
1k
f − Frequency − Hz
Figure 1.
10k 20k
THD+N −Total Harmonic Distortion + Noise − %
THD+N −Total Harmonic Distortion + Noise − %
10
1
0.1
VDD = 3.3 V
AV = −1 V/V
RL = 32 Ω
CB = 1 µF
PO = 15 mW
PO = 10 mW
0.01
PO = 30 mW
0.001
20
100
1k
10k 20k
f − Frequency − Hz
Figure 2.
5
TPA122
www.ti.com
SLOS211E – AUGUST 1998 – REVISED JUNE 2004
TOTAL HARMONIC DISTORTION + NOISE
vs
OUTPUT POWER
TOTAL HARMONIC DISTORTION + NOISE
vs
FREQUENCY
10
THD+N −Total Harmonic Distortion + Noise − %
THD+N −Total Harmonic Distortion + Noise − %
10
VDD = 3.3 V
RL = 32 Ω
AV = −1 V/V
CB = 1 µF
20 kHz
10 kHz
1
0.1
1 kHz
20 Hz
10
AV = −10 V/V
0.1
50
AV = −5 V/V
0.01
AV = −1 V/V
0.001
20
0.01
1
1
VDD = 5 V
PO = 60 mW
RL = 32 Ω
CB = 1 µF
100
PO − Output Power − mW
Figure 4.
TOTAL HARMONIC DISTORTION + NOISE
vs
FREQUENCY
TOTAL HARMONIC DISTORTION + NOISE
vs
OUTPUT POWER
THD+N −Total Harmonic Distortion + Noise − %
THD+N −Total Harmonic Distortion + Noise − %
10
VDD = 5 V
RL = 32 Ω
AV = −1 V/V
CB = 1 µF
1
PO = 30 mW
PO = 15 mW
0.01
PO = 60 mW
0.001
20
100
1k
f − Frequency − Hz
Figure 5.
6
10k 20k
Figure 3.
10
0.1
1k
f − Frequency − Hz
10k 20k
VDD = 5 V
AV = −1 V/V
RL = 32 Ω
CB = 1 µF
20 kHz
1
10 kHz
0.1
1 kHz
20 Hz
0.01
0.002
0.01
0.1
PO − Output Power − W
Figure 6.
0.2
TPA122
www.ti.com
SLOS211E – AUGUST 1998 – REVISED JUNE 2004
TOTAL HARMONIC DISTORTION + NOISE
vs
FREQUENCY
TOTAL HARMONIC DISTORTION + NOISE
vs
FREQUENCY
10
VDD = 3.3 V
RL = 10 kΩ
PO = 100 µF
CB = 1 µF
THD+N −Total Harmonic Distortion + Noise − %
THD+N −Total Harmonic Distortion + Noise − %
10
1
AV = −5 V/V
0.1
0.01
AV = −2 V/V
0.001
20
100
1k
VDD = 3.3 V
RL = 10 kΩ
AV = −1 V/V
CB = 1 µF
1
0.1
PO = 45 µW
0.01
0.001
20
10k 20k
100
f − Frequency − Hz
10k 20k
Figure 7.
Figure 8.
TOTAL HARMONIC DISTORTION + NOISE
vs
OUTPUT POWER
TOTAL HARMONIC DISTORTION + NOISE
vs
FREQUENCY
10
VDD = 3.3 V
RL = 10 kΩ
AV = −1 V/V
CB = 1 µF
1
0.1
20 Hz
10 kHz
0.01
20 Hz
1 kHz
0.001
5
1k
f − Frequency − Hz
THD+N −Total Harmonic Distortion + Noise − %
THD+N −Total Harmonic Distortion + Noise − %
10
PO = 90 µW
PO = 130 µW
10
100
PO − Output Power − µW
Figure 9.
200
1
VDD = 5 V
RL = 10 kΩ
PO = 300 µW
CB = 1 µF
0.1
AV = −5 V/V
AV = −1 V/V
0.01
AV = −2 V/V
0.001
20
100
1k
10k 20k
f − Frequency − Hz
Figure 10.
7
TPA122
www.ti.com
SLOS211E – AUGUST 1998 – REVISED JUNE 2004
TOTAL HARMONIC DISTORTION + NOISE
vs
FREQUENCY
TOTAL HARMONIC DISTORTION + NOISE
vs
OUTPUT POWER
1
10
VDD = 5 V
RL = 10 kΩ
AV = −1 V/V
CB = 1 µF
PO = 300 µW
0.1
PO = 200 µW
0.01
PO = 100 µW
0.001
20
THD+N −Total Harmonic Distortion + Noise − %
THD+N −Total Harmonic Distortion + Noise − %
10
VDD = 5 V
RL = 10 kΩ
AV = −1 V/V
CB = 1 µ F
1
0.1
20 Hz
20 kHz
0.01
10 kHz 1 kHz
0.001
100
1k
10k 20k
5
500
Figure 12.
TOTAL HARMONIC DISTORTION + NOISE
vs
FREQUENCY
TOTAL HARMONIC DISTORTION + NOISE
vs
FREQUENCY
10
VDD = 3.3 V
PO = 75 mW
RL = 8 Ω
CB = 1 µF
1
AV = −5 V/V
AV = −2 V/V
0.1
AV = −1 V/V
0.01
0.001
100
1k
f − Frequency − Hz
Figure 13.
10k 20k
THD+N −Total Harmonic Distortion + Noise − %
THD+N − Total Harmonic Distortion Plus Noise − %
100
Figure 11.
2
20
8
10
PO − Output Power − µW
f − Frequency − Hz
VDD = 3.3 V
RL = 8 Ω
AV = −1 V/V
PO = 30 mW
1
PO = 15 mW
0.1
0.01
PO = 75 mW
0.001
20
100
1k
f − Frequency − Hz
Figure 14.
10k 20k
TPA122
www.ti.com
SLOS211E – AUGUST 1998 – REVISED JUNE 2004
TOTAL HARMONIC DISTORTION + NOISE
vs
OUTPUT POWER
TOTAL HARMONIC DISTORTION + NOISE
vs
FREQUENCY
VDD = 3.3 V
RL = 8 Ω
AV = −1 V/V
THD+N − Total Harmonic Distortion Plus Noise − %
THD+N −Total Harmonic Distortion + Noise − %
10
20 kHz
10 kHz
1
1 kHz
0.1
20 Hz
0.01
10m
0.1
0.3
2
VDD = 5 V
PO = 100 mW
RL = 8 Ω
CB = 1 µF
1
AV = −1 V/V
0.01
0.001
20
100
10k 20k
Figure 15.
Figure 16.
TOTAL HARMONIC DISTORTION + NOISE
vs
FREQUENCY
TOTAL HARMONIC DISTORTION + NOISE
vs
OUTPUT POWER
10
THD+N −Total Harmonic Distortion + Noise − %
THD+N −Total Harmonic Distortion + Noise − %
1k
f − Frequency − Hz
10
VDD = 5 V
RL = 8 Ω
AV = −1 V/V
PO = 30 mW
1
PO = 60 mW
0.01
PO = 10 mW
0.001
20
AV = −5 V/V
0.1
PO − Output Power − W
0.1
AV = −2 V/V
100
1k
f − Frequency − Hz
Figure 17.
10k 20k
VDD = 5 V
RL = 8 Ω
AV = −1 V/V
20 kHz
1
10 kHz
1 kHz
0.1
20 Hz
0.01
10m
0.1
1
PO − Output Power − W
Figure 18.
9
TPA122
www.ti.com
SLOS211E – AUGUST 1998 – REVISED JUNE 2004
SUPPLY RIPPLE REJECTION RATIO
vs
FREQUENCY
SUPPLY RIPPLE REJECTION RATIO
vs
FREQUENCY
0
VDD = 3.3 V
RL = 8 Ω to 10 kΩ
−10
−20
CB = 0.1 µF
−30
CB = 1 µF
−40
−50
−60
CB = 2 µF
−70
Bypass = 1.65 V
−80
−90
−100
20
VDD = 5 V
RL = 8 Ω to 10 kΩ
−10
Supply Ripple Rejection Ratio − dB
Supply Ripple Rejection Ratio − dB
0
−20
CB = 0.1 µF
−30
CB = 1 µF
−40
−50
−60
CB = 2 µF
−70
−80
−90
100
1k
−100
20
10k 20k
Bypass = 2.5 V
100
f − Frequency − Hz
Figure 19.
Figure 20.
OUTPUT NOISE VOLTAGE
vs
FREQUENCY
OUTPUT NOISE VOLTAGE
vs
FREQUENCY
Vn − Output Noise Voltage − µV
Vn − Output Noise Voltage − µV
10
VDD = 3.3 V
BW = 10 Hz to 22 kHz
AV = −1 V/V
RL = 8 Ω to 10 kΩ
100
1k
f − Frequency − Hz
Figure 21.
10
10k 20k
20
20
1
20
1k
f − Frequency − Hz
10k 20k
10
VDD = 5 V
BW = 10 Hz to 22 kHz
RL = 8 Ω to 10 kΩ
AV = −1 V/V
1
20
100
1k
f − Frequency − Hz
Figure 22.
10k 20k
TPA122
www.ti.com
SLOS211E – AUGUST 1998 – REVISED JUNE 2004
CROSSTALK
vs
FREQUENCY
CROSSTALK
vs
FREQUENCY
−50
−60
−70
Crosstalk − dB
−75
−60
−65
−80
IN2 TO OUT1
−85
−90
−95
−70
−75
IN2 TO OUT1
−80
−85
−100
IN1 TO OUT2
−90
IN1 TO OUT2
−105
−110
20
PO = 100 mW
VDD = 3.3 V
RL = 8 Ω
CB = 1 µF
AV = −1 V/V
−55
Crosstalk − dB
−65
PO = 25 mW
VDD = 3.3 V
RL = 32 Ω
CB = 1 µF
AV = −1 V/V
−95
−100
100
1k
10k 20k
20
100
f − Frequency − Hz
Figure 23.
Figure 24.
CROSSTALK
vs
FREQUENCY
CROSSTALK
vs
FREQUENCY
−60
10k 20k
−50
VDD = 5 V
PO = 25 mW
CB = 1 µF
RL = 32 Ω
AV = −1 V/V
−65
−75
−80
−85
−55
−60
−65
Crosstalk − dB
−65
Crosstalk − dB
1k
f − Frequency − Hz
IN2 TO OUT1
−90
−95
VDD = 5 V
PO = 100 mW
CB = 1 µF
RL = 8 Ω
AV = −1 V/V
−70
IN2 TO OUT1
−75
−80
−85
−100
−90
IN1 TO OUT2
IN1 TO OUT2
−105
−110
20
−95
100
1k
10k 20k
−100
20
100
1k
f − Frequency − Hz
f − Frequency − Hz
Figure 25.
Figure 26.
10k 20k
11
TPA122
www.ti.com
SLOS211E – AUGUST 1998 – REVISED JUNE 2004
MUTE ATTENUATION
vs
FREQUENCY
MUTE ATTENUATION
vs
FREQUENCY
0
Mute Attenuation − dB
−20
−20
−30
−40
−50
−60
−70
−30
−40
−50
−60
−70
−80
−80
−90
−90
−100
20
VDD = 5 V
CB = 1 µF
RL = 32 Ω
−10
Mute Attenuation − dB
−10
0
VDD = 3.3 V
RL = 32 Ω
CB = 1 µF
100
1k
−100
20
10k 20k
100
f − Frequency − Hz
1k
f − Frequency − Hz
Figure 27.
Figure 28.
OPEN-LOOP GAIN AND PHASE MARGIN
vs
FREQUENCY
150°
VDD = 3.3 V
TA = 25°C
No Load
Open-Loop Gain − dB
80
Phase
60
40
90°
60°
Gain
20
30°
0
0°
−20
10
100
1k
10k
f − Frequency − Hz
Figure 29.
12
120°
100k
−30°
10M
φ m − Phase Margin
100
10k 20k
TPA122
www.ti.com
SLOS211E – AUGUST 1998 – REVISED JUNE 2004
OPEN-LOOP GAIN AND PHASE MARGIN
vs
FREQUENCY
100
150°
VDD = 5 V
TA = 25°C
No Load
120°
Phase
60
40
90°
60°
Gain
20
30°
0
0°
−20
100
1k
10k
100k
φ m − Phase Margin
Open-Loop Gain − dB
80
−30°
10M
1M
f − Frequency − Hz
Figure 30.
OUTPUT POWER
vs
LOAD RESISTANCE
OUTPUT POWER
vs
LOAD RESISTANCE
300
120
THD+N = 1 %
VDD = 3.3 V
AV = −1 V/V
250
PO − Output Power − mW
PO − Output Power − mW
100
THD+N = 1 %
VDD = 5 V
AV = −1 V/V
80
60
40
200
150
100
50
20
0
0
8
16
24
32
40
48
RL − Load Resistance − Ω
Figure 31.
56
64
8
16
24
32
40
48
56
64
RL − Load Resistance − Ω
Figure 32.
13
TPA122
www.ti.com
SLOS211E – AUGUST 1998 – REVISED JUNE 2004
SUPPLY CURRENT
vs
SUPPLY VOLTAGE
TOTAL HARMONIC DISTORTION + NOISE
vs
FREQUENCY
THD+N − Total Harmonic Distortion Plus Noise − %
1.4
I DD − Supply Current − mA
1.2
1
0.8
0.6
0.4
0.2
0
2.5
3
3.5
4
4.5
5
1
VI = 1 V
AV = −1 V/V
RL = 10 kΩ
CB = 1 µF
0.1
0.01
0.001
5.5
20
100
Figure 34.
SIGNAL-TO-NOISE RATIO
vs
VOLTAGE GAIN
TOTAL HARMONIC DISTORTION + NOISE
vs
FREQUENCY
THD+N − Total Harmonic Distortion Plus Noise − %
SNR − Signal-to-Noise Ratio − dB
VI = 1 V
102
100
98
96
94
92
2
3
4
5
6
7
AV − Voltage Gain − V/V
Figure 35.
14
10k 20k
Figure 33.
104
1
1k
f − Frequency − Hz
VDD − Supply Voltage − V
8
9
10
1
VDD = 5 V
AV = −1 V/V
RL = 10 kΩ
CB = 1 µF
0.1
0.01
0.001
20
100
1k
f − Frequency − Hz
Figure 36.
10k 20k
TPA122
www.ti.com
SLOS211E – AUGUST 1998 – REVISED JUNE 2004
CROSSTALK
vs
FREQUENCY
CROSSTALK
vs
FREQUENCY
−60
−60
−70
−80
Crosstalk − dB
−90
−100
IN2 to OUT1
−110
−90
−100
−120
IN2 to OUT1
−110
−120
−130
−130
IN1 to OUT2
−140
IN1 to OUT2
−140
−150
−150
100
1k
20
10k 20k
100
f − Frequency − Hz
1k
10k 20k
f − Frequency − Hz
Figure 37.
Figure 38.
CLOSED-LOOP GAIN AND PHASE
vs
FREQUENCY
200°
180°
Phase
160°
140°
Phase
20
120°
Closed-Loop Gain − dB
Crosstalk − dB
−80
VDD = 5 V
VO = 1 V
RL = 10 kΩ
CB = 1 µF
−70
VDD = 3.3 V
VO = 1 V
RL = 10 kΩ
CB = 1 µF
VDD = 3.3 V
RI = 20 kΩ
RF = 20 kΩ
RL = 32 Ω
CI = 1 µF
AV = −1 V/V
30
20
10
100°
80°
Gain
0
−10
10
100
1k
10k
100k
1M
f − Frequency − Hz
Figure 39.
15
TPA122
www.ti.com
SLOS211E – AUGUST 1998 – REVISED JUNE 2004
CLOSED-LOOP GAIN AND PHASE
vs
FREQUENCY
200°
180°
160°
140°
Phase
Phase
Closed-Loop Gain − dB
120°
VDD = 5 V
RI = 20 kΩ
RF = 20 kΩ
RL = 32 Ω
CI = 1 µF
AV = −1 V/V
30
100°
80°
20
10
Gain
0
−10
10
100
1k
10k
100k
1M
f − Frequency − Hz
Figure 40.
CLOSED-LOOP GAIN AND PHASE
vs
FREQUENCY
200°
180°
Phase
140°
Closed-Loop Gain − dB
120°
VDD = 3.3 V
RI = 20 kΩ
RF = 20 kΩ
RL = 8 Ω
CI = 1 µF
AV = −1 V/V
40
80°
60°
Gain
20
0
−20
10
100
1k
10k
f − Frequency − Hz
Figure 41.
16
100°
100k
1M
Phase
160°
TPA122
www.ti.com
SLOS211E – AUGUST 1998 – REVISED JUNE 2004
CLOSED-LOOP GAIN AND PHASE
vs
FREQUENCY
200°
160°
140°
Phase
180°
Phase
Closed-Loop Gain − dB
120°
VDD = 3.3 V
RI = 20 kΩ
RF = 20 kΩ
RL = 10 kΩ
CI = 1 µF
AV = −1 V/V
30
20
10
100°
80°
Gain
0
−10
10
100
1k
10k
100k
1M
f − Frequency − Hz
Figure 42.
CLOSED-LOOP GAIN AND PHASE
vs
FREQUENCY
200°
180°
Phase
Closed-Loop Gain − dB
140°
VDD = 5 V
RI = 20 kΩ
RF = 20 kΩ
RL = 8 Ω
CI = 1 µF
AV = −1 V/V
120°
Phase
160°
100°
80°
60°
40°
Gain
20
0
−20
10
100
1k
10k
100k
1M
f − Frequency − Hz
Figure 43.
17
TPA122
www.ti.com
SLOS211E – AUGUST 1998 – REVISED JUNE 2004
CLOSED-LOOP GAIN AND PHASE
vs
FREQUENCY
200°
160°
Closed-Loop Gain − dB
140°
120°
VDD = 5 V
RI = 20 kΩ
RF = 20 kΩ
RL = 10 kΩ
CI = 1 µF
AV = −1 V/V
30
Phase
180°
Phase
100°
80°
20
10
Gain
0
−10
10
100
1k
10k
100k
1M
f − Frequency − Hz
Figure 44.
POWER DISSIPATION/AMPLIFIER
vs
OUTPUT POWER
POWER DISSIPATION/AMPLIFIER
vs
OUTPUT POWER
80
180
VDD = 3.3 V
VDD = 5 V
8Ω
70
140
Amplifier Power − mW
Amplifier Power − mW
60
50
40
16 Ω
30
32 Ω
20
120
100
16 Ω
80
60
32 Ω
40
64 Ω
10
64 Ω
20
0
0
0
20
40
60
80 100 120 140 160 180
Load Power − mW
Figure 45.
18
8Ω
160
200
0
20
40
60
80 100 120 140 160 180
Load Power − mW
Figure 46.
200
TPA122
www.ti.com
SLOS211E – AUGUST 1998 – REVISED JUNE 2004
APPLICATION INFORMATION
GAIN SETTING RESISTORS, RF and RI
The gain for the TPA122 is set by resistors RF and RI according to Equation 1.
Gain RF
RI
(1)
Given that the TPA122 is an MOS amplifier, the input impedance is high. Consequently, input leakage currents
are not generally a concern, although noise in the circuit increases as the value of RF increases. In addition, a
certain range of RF values is required for proper start-up operation of the amplifier. Taken together, 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 FR I
Effective Impedance RF RI
(2)
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.
For high-performance applications, metal film resistors are recommended because they tend to have lower noise
levels than carbon resistors. For values of RF above 50 kΩ, the amplifier tends to become unstable due to a pole
formed from RF and the inherent input capacitance of the MOS input structure. For this reason, a small
compensation capacitor of approximately 5 pF should be placed in parallel with RF. In effect, this creates a
low-pass filter network with the cutoff frequency defined in Equation 3.
1
f c(lowpass) 2 R F CF
(3)
For example, if RF is 100 kΩ and CF is 5 pF, then fc(lowpass) is 318 kHz, which is well outside the audio range.
INPUT CAPACITOR CI
In the typical application, an input capacitor, CI, is required to allow the amplifier to bias the input signal to the
proper dc level for optimum operation. In this case, CI and RI form a high-pass filter with the corner frequency
determined in Equation 4.
1
f c(highpass) 2 R I CI
(4)
The value of CI is important to consider, as it directly affects the bass (low-frequency) performance of the circuit.
Consider the example where RI is 20 kΩ and the specification calls for a flat bass response down to 20 Hz.
Equation 4 is reconfigured as Equation 5.
1
CI 2 R I f c(highpass)
(5)
In this example, CI is 0.4 µF, so one would likely choose a value in the range of 0.47 µF to 1 µF. A further
consideration for this capacitor is the leakage path from the input source through the input network (RI, CI) and
the feedback resistor (RF) to the load. This leakage current creates a dc offset voltage at the input to the amplifier
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 VDD/2, which is likely higher
than the source dc level. Note that it is important to confirm the capacitor polarity in the application.
19
TPA122
www.ti.com
SLOS211E – AUGUST 1998 – REVISED JUNE 2004
APPLICATION INFORMATION (continued)
POWER SUPPLY DECOUPLING, CS
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 VDD lead, works best. For filtering
lower frequency noise signals, a larger aluminum electrolytic capacitor of 10 µF or greater placed near the power
amplifier is recommended.
MIDRAIL BYPASS CAPACITOR, CB
The midrail bypass capacitor, CB, serves several important functions. During start-up, CB determines the rate 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 into the
output drive signal. This noise is from the midrail generation circuit internal to the amplifier. The capacitor 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
C B 160 kΩ C I R I
(6)
As an example, consider a circuit where CB is 1 µF, CI is 1 µF, and RI is 20 kΩ. Inserting these values into
Equation 6 results in: 6.25 ≤ 50 which satisfies the rule. Bypass capacitor, CB, values of 0.1-µF to 1-µF ceramic
or tantalum low-ESR capacitors are recommended for the best THD and noise performance.
OUTPUT COUPLING CAPACITOR, CC
In the typical single-supply, single-ended (SE) configuration, an output coupling capacitor (CC) is required to
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
fc 2 R L CC
(7)
The main disadvantage, from a performance standpoint, is that the typically small load impedances drive the
low-frequency corner higher. Large values of CC are required to pass low frequencies into the load. Consider the
example where a CC of 68 µF is chosen and loads vary from 32 Ω to 47 kΩ. Table 1 summarizes the frequency
response characteristics of each configuration.
Table 1. Common Load Impedances vs Low Frequency Output Characteristics
in SE Mode
RL
CC
LOWEST FREQUENCY
32 Ω
68 µF
73 Hz
10,000 Ω
68 µF
0.23 Hz
47,000 Ω
68 µF
0.05 Hz
As Table 1 indicates, headphone response is adequate and drive into line level inputs (a home stereo for
example) is 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:
20
TPA122
www.ti.com
1
C B 160 kΩ
SLOS211E – AUGUST 1998 – REVISED JUNE 2004
1
C I R I
1
R LC C
(8)
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 2.5 V to 5.5 V. This data sheet provides full
specifications for 5-V and 3.3-V operation because 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. The most important consideration is that of output power. Each amplifier in the TPA122 can
produce a maximum voltage swing of VDD – 1 V. This means, for 3.3-V operation, clipping starts to occur when
VO(PP) = 2.3 V, as opposed to VO(PP) = 4 V for 5-V operation. The reduced voltage swing subsequently reduces
maximum output power into the load before distortion begins to become significant.
21
Thermal Pad Mechanical Data
www.ti.com
DGN (S–PDSO–G8)
THERMAL INFORMATION
The DGN PowerPAD™ package incorporates an exposed thermal die pad that is designed to be attached directly
to an external heat sink. When the thermal die pad is soldered directly to the printed circuit board (PCB), the PCB
can be used as a heatsink. In addition, through the use of thermal vias, the thermal die pad can be attached directly
to a ground plane or special heat sink structure designed into the PCB. This design optimizes the heat transfer from
the integrated circuit (IC).
For additional information on the PowerPAD package and how to take advantage of its heat dissipating abilities, refer to
Technical Brief, PowerPAD Thermally Enhanced Package, Texas Instruments Literature No. SLMA002 and
Application Brief, PowerPAD Made Easy, Texas Instruments Literature No. SLMA004. Both documents are available
at www.ti.com. See Figure 1 for DGN package exposed thermal die pad dimensions.
8
1
5
4
Exposed Thermal
Die Pad
1,78
MAX
1,73
MAX
Bottom View
PPTD041
NOTE: All linear dimensions are in millimeters.
Figure 1. DGN Package Exposed Thermal Die Pad Dimensions
PowerPAD is a trademark of Texas Instruments.
1
PACKAGE OPTION ADDENDUM
www.ti.com
21-Feb-2005
PACKAGING INFORMATION
Orderable Device
Status (1)
Package
Type
Package
Drawing
Pins Package Eco Plan (2)
Qty
TPA122D
ACTIVE
SOIC
D
8
75
Pb-Free
(RoHS)
CU NIPDAU
Level-2-260C-1YEAR/
Level-1-220C-UNLIM
TPA122DGN
ACTIVE
MSOPPower
PAD
DGN
8
80
None
CU NIPDAU
Level-1-220C-UNLIM
TPA122DGNR
ACTIVE
MSOPPower
PAD
DGN
8
2500
None
CU NIPDAU
Level-1-220C-UNLIM
TPA122DGNRG4
ACTIVE
MSOPPower
PAD
DGN
8
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TPA122DR
ACTIVE
SOIC
D
8
2500
Pb-Free
(RoHS)
CU NIPDAU
Level-2-260C-1YEAR/
Level-1-220C-UNLIM
TPA122EVM
OBSOLETE
None
Call TI
0
Lead/Ball Finish
MSL Peak Temp (3)
Call TI
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in
a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
Eco Plan - May not be currently available - please check http://www.ti.com/productcontent for the latest availability information and additional
product content details.
None: Not yet available Lead (Pb-Free).
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements
for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered
at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Green (RoHS & no Sb/Br): TI defines "Green" to mean "Pb-Free" and in addition, uses package materials that do not contain halogens,
including bromine (Br) or antimony (Sb) above 0.1% of total product weight.
(3)
MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDECindustry standard classifications, and peak solder
temperature.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is
provided. TI bases its knowledge and belief on information provided by third parties, and makes no representation or warranty as to the
accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and continues to take
reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on
incoming materials and chemicals. TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited
information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI
to Customer on an annual basis.
Addendum-Page 1
IMPORTANT NOTICE
Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, modifications,
enhancements, improvements, and other changes to its products and services at any time and to discontinue
any product or service without notice. Customers should obtain the latest relevant information before placing
orders and should verify that such information is current and complete. All products are sold subject to TI’s terms
and conditions of sale supplied at the time of order acknowledgment.
TI warrants performance of its hardware products to the specifications applicable at the time of sale in
accordance with TI’s standard warranty. Testing and other quality control techniques are used to the extent TI
deems necessary to support this warranty. Except where mandated by government requirements, testing of all
parameters of each product is not necessarily performed.
TI assumes no liability for applications assistance or customer product design. Customers are responsible for
their products and applications using TI components. To minimize the risks associated with customer products
and applications, customers should provide adequate design and operating safeguards.
TI does not warrant or represent that any license, either express or implied, is granted under any TI patent right,
copyright, mask work right, or other TI intellectual property right relating to any combination, machine, or process
in which TI products or services are used. Information published by TI regarding third-party products or services
does not constitute a license from TI to use such products or services or a warranty or endorsement thereof.
Use of such information may require a license from a third party under the patents or other intellectual property
of the third party, or a license from TI under the patents or other intellectual property of TI.
Reproduction of information in TI data books or data sheets is permissible only if reproduction is without
alteration and is accompanied by all associated warranties, conditions, limitations, and notices. Reproduction
of this information with alteration is an unfair and deceptive business practice. TI is not responsible or liable for
such altered documentation.
Resale of TI products or services with statements different from or beyond the parameters stated by TI for that
product or service voids all express and any implied warranties for the associated TI product or service and
is an unfair and deceptive business practice. TI is not responsible or liable for any such statements.
Following are URLs where you can obtain information on other Texas Instruments products and application
solutions:
Products
Applications
Amplifiers
amplifier.ti.com
Audio
www.ti.com/audio
Data Converters
dataconverter.ti.com
Automotive
www.ti.com/automotive
DSP
dsp.ti.com
Broadband
www.ti.com/broadband
Interface
interface.ti.com
Digital Control
www.ti.com/digitalcontrol
Logic
logic.ti.com
Military
www.ti.com/military
Power Mgmt
power.ti.com
Optical Networking
www.ti.com/opticalnetwork
Microcontrollers
microcontroller.ti.com
Security
www.ti.com/security
Telephony
www.ti.com/telephony
Video & Imaging
www.ti.com/video
Wireless
www.ti.com/wireless
Mailing Address:
Texas Instruments
Post Office Box 655303 Dallas, Texas 75265
Copyright  2005, Texas Instruments Incorporated