SLOS324B − JUNE 2000 − REVISED SEPTEMBER 2004
D
D
D
D
D
D
D
D
D
D
D or DGK PACKAGE
(TOP VIEW)
50-mW Stereo Output
Low Supply Current . . . 0.75 mA
Low Shutdown Current . . . 50 nA
Minimal External Components Required
Gain Set Internally to 14 dB
Pop Reduction Circuitry
Internal Mid-Rail Generation
Thermal and Short-Circuit Protection
Surface-Mount Packaging
− MSOP
− SOIC
1.6-V to 3.6-V Supply Voltage Range
BYPASS
GND
SHUTDOWN
IN2−
1
8
2
7
3
6
4
5
IN1−
VO 1
VDD
VO 2
description
The TPA6102A2 is a stereo audio power amplifier packaged in either an 8-pin SOIC package or an 8-pin MOSP
package capable of delivering 50 mW of continuous RMS power per channel into 16-Ω loads. Amplifier gain
is internally set to 14 dB (inverting) to save board space by eliminating six external resistors.
The TPA6102A2 is optimized for battery applications because of its low-supply current, shutdown current, and
THD+N. To obtain the low-supply voltage range, the TPA6102A2 biases BYPASS to VDD/4.
When driving a 16-Ω load with 40-mW output power from 3.3 V, THD+N is 0.08% at 1 kHz, and less than 0.2%
across the audio band of 20 Hz to 20 kHz. For 30 mW into 32-Ω loads, the THD+N is reduced to less than 0.06%
at 1 kHz, and is less than 0.3% across the audio band of 20 Hz to 20 kHz.
typical application circuit
VDD 6
100 kΩ
Audio
Input
VDD/4
8 IN 1−
20 kΩ
CI
100 kΩ
−
+
VO1 7
−
+
VO2 5
VDD
CS
CC
1 BYPASS
CB
Audio
Input
4 IN 2−
20 kΩ
CI
From Shutdown
Control Circuit
CC
100 kΩ
3
SHUTDOWN
Bias
Control
2
100 kΩ
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 2004, Texas Instruments Incorporated
!"
#$! % &'""($ #% ! )'*+&#$! ,#$("!,'&$% &!!"
$! %)(&&#$!% )(" $.( $("
% ! (/#% %$"'
($%
%$#,#", 0#""#$1- "!,'&$! )"!&(%%2 ,!(% !$ (&(%%#"+1 &+',(
$(%$2 ! #++ )#"#
($("%-
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
1
SLOS324B − JUNE 2000 − REVISED SEPTEMBER 2004
AVAILABLE OPTIONS
PACKAGED DEVICE
TA
SMALL OUTLINE (D)
MSOP (DGK)
MSOP
SYMBOLIZATION
−40°C to 85°C
TPA6102A2D
TPA6102A2DGK
AJN
Terminal Functions
TERMINAL
NAME
NO.
I/O
DESCRIPTION
BYPASS
1
I
Tap to voltage divider for internal mid-supply bias supply. BYPASS is set at VDD/4. Connect to a 0.1-µF to 1-µF
low ESR capacitor for best performance.
GND
2
I
GND is the ground connection.
IN1−
8
I
IN1− is the inverting input for channel 1.
IN2−
4
I
IN2− is the inverting input for channel 2.
SHUTDOWN
3
I
Active-low input. When held low, the device is placed in a low supply current mode.
VDD
VO1
6
I
7
O
VDD is the supply voltage terminal.
VO1 is the audio output for channel 1.
VO2
5
O
VO2 is the audio output for channel 2.
absolute maximum ratings over operating free-air temperature (unless otherwise noted)†
Supply voltage, VDD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 V
Input voltage, VI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.3 V to VDD + 0.3 V
Continuous total power dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Internally Limited
Operating junction temperature range, TJ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −40°C to 150°C
Storage temperature range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −65°C to 150°C
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
PACKAGE
TA ≤ 25°C
POWER RATING
DERATING FACTOR
ABOVE TA = 25°C
TA = 70°C
POWER RATING
TA = 85°C
POWER RATING
D
710 mW
5.68 mW/°C
454 mW
369 mW
DGK
469 mW
3.75 mW/°C
300 mW
244 mW
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
recommended operating conditions
Supply voltage, VDD
MIN
MAX
1.6
3.6
60% x VDD
High-level input voltage, VIH (SHUTDOWN)
Low-level input voltage, VIL (SHUTDOWN)
Operating free-air temperature, TA
2
−40
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
UNIT
V
V
25% x VDD
V
85
°C
SLOS324B − JUNE 2000 − REVISED SEPTEMBER 2004
dc electrical characteristics at TA = 25°C, VDD = 3.6 V (unless otherwise noted)
PARAMETER
TEST CONDITIONS
VOO
PSRR
Output offset voltage
Power supply rejection ratio
AV = 14 dB
VDD = 3 V to 3.6 V
IDD
Supply current
SHUTDOWN = 3.6 V
IDD(SD)
Supply current in SHUTDOWN mode
SHUTDOWN = 0 V
|IIH|
High-level input current (SHUTDOWN)
|IIL|
Low-level input current (SHUTDOWN)
VDD = 3.6 V, VI= VDD
VDD = 3.6 V, VI= 0 V
ZI
Input impedance
MIN
TYP
MAX
5
40
72
UNIT
mV
dB
0.75
1.5
mA
50
250
nA
1
µA
1
20
µA
kΩ
ac operating characteristics, VDD = 3.3 V, TA = 25°C, RL = 16 Ω
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
G
Gain
14
dB
PO
THD+N
Output power (each channel)
THD ≤ 0.1%,
f = 1 kHz
Total harmonic distortion + noise
20−20 kHz
BOM
kSVR
Maximum output power BW
PO = 45 mW,
THD < 0.5%
50
mW
> 20
kHz
Supply ripple rejection ratio
f = 1 kHz
47
dB
SNR
Signal-to-noise ratio
PO = 50 mW
86
dB
Vn
Noise output voltage (no noise weighting filter)
45
µV(rms)
0.4%
ac operating characteristics, VDD = 3.3 V, TA = 25°C, RL = 32 Ω
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
G
Gain
PO
THD+N
Output power (each channel)
THD ≤ 0.1%,
f = 1 kHz
Total harmonic distortion + noise
Maximum output power BW
PO = 30 mW,
THD < 0.4%
20−20 kHz
BOM
kSVR
> 20
kHz
Supply ripple rejection ratio
f = 1 kHz
47
dB
SNR
Signal-to-noise ratio
PO = 30 mW
86
dB
Vn
Noise output voltage (no noise weighting filter)
50
µV(rms)
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
14
dB
35
mW
0.4%
3
SLOS324B − JUNE 2000 − REVISED SEPTEMBER 2004
dc electrical characteristics at TA = 25°C, VDD = 1.6 V (unless otherwise noted)
PARAMETER
VOO
PSRR
Output offset voltage
TEST CONDITIONS
MIN
TYP
MAX
5
40
UNIT
Power supply rejection ratio
AV = 14 dB
VDD = 1.4 V to 1.8 V
80
mV
IDD
Supply current
SHUTDOWN = 1.6 V
0.65
1.2
mA
IDD(SD)
Supply current in SHUTDOWN mode
SHUTDOWN = 0 V
50
250
nA
|IIH|
High-level input current (SHUTDOWN)
µA
Low-level input current (SHUTDOWN)
VDD = 1.6 V, VI = VDD
VDD = 1.6 V, VI = 0 V
1
|IIL|
ZI
Input impedance
dB
1
20
µA
kΩ
ac operating characteristics, VDD = 1.6 V, TA = 25°C, RL = 16 Ω
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
G
Gain
14
dB
PO
THD+N
Output power (each channel)
THD ≤ 0.5%,
f = 1 kHz
Total harmonic distortion + noise
20−20 kHz
BOM
kSVR
Maximum output power BW
PO = 9.5 mW,
THD < 1%
10
mW
> 20
kHz
Supply ripple rejection ratio
f = 1 kHz
47
dB
SNR
Signal-to-noise ratio
PO = 10 mW
82
dB
Vn
Noise output voltage (no noise weighting filter)
32
µV(rms)
0.06%
ac operating characteristics, VDD = 1.6 V, TA = 25°C, RL = 32 Ω
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
G
Gain
PO
THD+N
Output power (each channel)
THD ≤ 0.5%,
f = 1 kHz
14
dB
7.5
mW
Total harmonic distortion + noise
Maximum output power BW
PO = 6.5 mW,
THD < 1%
20−20 kHz
BOM
kSVR
> 20
kHz
Supply ripple rejection ratio
f = 1 kHz
47
dB
SNR
Signal-to-noise ratio
PO = 7.5 mW
84
dB
Vn
Noise output voltage (no noise weighting filter)
32
µV(rms)
0.05%
TYPICAL CHARACTERISTICS
Table of Graphs
FIGURE
vs Frequency
THD+N
1, 3, 5, 7, 9, 11
vs Output power
2, 4, 6, 8, 10, 12
vs Output voltage
13, 14
PO
kSVR
Output power
vs Load resistance
15, 16
Supply ripple rejection ratio
vs Frequency
17, 18
Vn
Output noise voltage
vs Frequency
19, 20
Crosstalk
vs Frequency
21, 22
Closed−loop gain and phase
vs Frequency
23, 24, 25, 26
Supply current
vs Supply voltage
27
Power dissipation
vs Output power
28
IDD
PD
4
Total harmonic distortion plus noise
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
SLOS324B − JUNE 2000 − REVISED SEPTEMBER 2004
TYPICAL CHARACTERISTICS
TOTAL HARMONIC DISTORTION PLUS NOISE
vs
OUTPUT POWER
10
1
THD+N − Total Harmonic Distortion Plus Noise − %
THD+N − Total Harmonic Distortion Plus Noise − %
TOTAL HARMONIC DISTORTION PLUS NOISE
vs
FREQUENCY
VDD = 1.6 V
PO = 9.5 mW
CB = 1 µF
RL = 16 Ω
0.1
0.01
0.001
0.0001
20
100
1k
f − Frequency − Hz
10 k
10
VDD = 1.6 V
CB = 1 µF
RL = 16 Ω
f = 1 kHz
1
0.1
0.01
0.001
1
20 k
10
PO − Output Power − mW
Figure 1
Figure 2
10
VDD = 1.6 V
PO = 6.5 mW
CB = 1 µF
RL = 32 Ω
0.1
0.01
0.001
0.0001
20
100
TOTAL HARMONIC DISTORTION PLUS NOISE
vs
OUTPUT POWER
THD+N − Total Harmonic Distortion Plus Noise − %
THD+N − Total Harmonic Distortion Plus Noise − %
TOTAL HARMONIC DISTORTION PLUS NOISE
vs
FREQUENCY
1
1k
f − Frequency − Hz
100
10 k 20 k
10
VDD = 1.6 V
CB = 1 µF
RL = 32 Ω
f = 1 kHz
1
0.1
0.01
0.001
1
Figure 3
10
PO − Output Power − mW
100
Figure 4
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
5
SLOS324B − JUNE 2000 − REVISED SEPTEMBER 2004
TYPICAL CHARACTERISTICS
10
VDD = 1.6 V
PO = 4.5 mW
CB = 1 µF
RL = 50 Ω
1
0.1
0.01
0.001
0.0001
20
100
TOTAL HARMONIC DISTORTION PLUS NOISE
vs
OUTPUT POWER
THD+N − Total Harmonic Distortion Plus Noise − %
THD+N − Total Harmonic Distortion Plus Noise − %
TOTAL HARMONIC DISTORTION PLUS NOISE
vs
FREQUENCY
1k
f − Frequency − Hz
10 k 20 k
10
VDD = 1.6 V
CB = 1 µF
RL = 50 Ω
f = 1 kHz
1
0.1
0.01
0.001
1
10
PO − Output Power − mW
Figure 5
Figure 6
10
VDD = 3.3 V
PO = 45 mW
CB = 1 µF
RL = 16 Ω
0.1
0.01
0.001
0.0001
20
100
TOTAL HARMONIC DISTORTION PLUS NOISE
vs
OUTPUT POWER
THD+N − Total Harmonic Distortion Plus Noise − %
THD+N − Total Harmonic Distortion Plus Noise − %
TOTAL HARMONIC DISTORTION PLUS NOISE
vs
FREQUENCY
1
1k
f − Frequency − Hz
10 k 20 k
10
1
VDD = 3.3 V
CB = 1 µF
RL = 16 Ω
f = 1 kHz
0.1
0.01
0.001
0.0001
20
Figure 7
6
100
100
1k
PO − Output Power − mW
Figure 8
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
10 k 20 k
SLOS324B − JUNE 2000 − REVISED SEPTEMBER 2004
TYPICAL CHARACTERISTICS
10
1
VDD = 3.3 V
PO = 30 mW
CB = 1 µF
RL = 32 Ω
0.1
0.01
0.001
0.0001
20
100
TOTAL HARMONIC DISTORTION PLUS NOISE
vs
OUTPUT POWER
THD+N − Total Harmonic Distortion Plus Noise − %
THD+N − Total Harmonic Distortion Plus Noise − %
TOTAL HARMONIC DISTORTION PLUS NOISE
vs
FREQUENCY
1k
f − Frequency − Hz
10
VDD = 3.3 V
CB = 1 µF
RL = 32 Ω
f = 1 kHz
1
0.1
0.01
0.001
10 k 20 k
1
10
PO − Output Power − mW
Figure 9
VDD = 3.3 V
PO = 20 mW
CB = 1 µF
RL = 50 Ω
0.1
0.01
0.001
100
TOTAL HARMONIC DISTORTION PLUS NOISE
vs
OUTPUT POWER
THD+N − Total Harmonic Distortion Plus Noise − %
THD+N − Total Harmonic Distortion Plus Noise − %
10
0.0001
20
1k
f − Frequency − Hz
200
Figure 10
TOTAL HARMONIC DISTORTION PLUS NOISE
vs
FREQUENCY
1
100
10 k 20 k
10
VDD = 3.3 V
CB = 1 µF
RL = 50 Ω
f = 1 kHz
1
0.1
0.01
0.001
1
Figure 11
10
PO − Output Power − mW
100
200
Figure 12
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
7
SLOS324B − JUNE 2000 − REVISED SEPTEMBER 2004
TYPICAL CHARACTERISTICS
TOTAL HARMONIC DISTORTION PLUS NOISE
vs
OUTPUT VOLTAGE
10
THD+N − Total Harmonic Distortion Plus Noise − %
THD+N − Total Harmonic Distortion Plus Noise − %
TOTAL HARMONIC DISTORTION PLUS NOISE
vs
OUTPUT VOLTAGE
VDD = 1.6 V
RL = 10 kΩ
Frequency = 20 Hz
1
0.1
0.01
0.001
0
0.1 0.2 0.3 0.4
0.5 0.6 0.7 0.8
0.9
10
VDD = 3.3 V
RL = 10 kΩ
Frequency = 20 Hz
1
0.1
0.01
0.001
1
0
0.2
VO − Output Voltage − V
Figure 13
150
VDD = 1.6 V
THD+N = 1%
Mode = Stereo
VDD = 3.6 V
THD+N = 1%
Mode = Stereo
125
PO − Output Power − mW
12
PO − Output Power − mW
1.4
OUTPUT POWER
vs
LOAD RESISTANCE
15
9
6
3
100
75
50
25
20
24
28
32
36
40
44
48 50
0
16
20
RL − Load Resistance − Ω
Figure 15
8
1.2
Figure 14
OUTPUT POWER
vs
LOAD RESISTANCE
0
16
0.4
0.6
0.8
1
VO − Output Voltage − V
24
28
32
36
40
RL − Load Resistance − Ω
Figure 16
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
44
48 50
SLOS324B − JUNE 2000 − REVISED SEPTEMBER 2004
TYPICAL CHARACTERISTICS
SUPPLY RIPPLE REJECTION RATIO
vs
FREQUENCY
SUPPLY RIPPLE REJECTION RATIO
vs
FREQUENCY
0
VDD = 1.6 V
CB = 1 µF
RL = 32 Ω
−10
−20
k SVR− Supply Ripple Rejection Ratio − dB
k SVR− Supply Ripple Rejection Ratio − dB
0
−30
−40
−50
−60
−70
−80
−90
−100
−110
VDD = 3.3 V
CB = 1 µF
RL = 32 Ω
−10
−20
−30
−40
−50
−60
−70
−80
−90
−100
−110
−120
−120
10
100
1k
10
10 k 20 k
100
1k
f − Frequency − Hz
f − Frequency − Hz
Figure 17
Figure 18
OUTPUT NOISE VOLTAGE
vs
FREQUENCY
OUTPUT NOISE VOLTAGE
vs
FREQUENCY
100
V n − Output Noise Voltage − µ V(rms)
100
V n − Output Noise Voltage − µ V(rms)
10 k 20 k
10
VDD = 1.6 V
CB = 1 µF
RL = 16 Ω
10
VDD = 3.3 V
CB = 1 µF
RL = 16 Ω
1
1
20
100
1k
f − Frequency − Hz
10 k
20 k
20
Figure 19
100
1k
f − Frequency − Hz
10 k 20 k
Figure 20
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
9
SLOS324B − JUNE 2000 − REVISED SEPTEMBER 2004
TYPICAL CHARACTERISTICS
CROSSTALK
vs
FREQUENCY
CROSSTALK
vs
FREQUENCY
0
0
−10
−20
−20
−30
−40
−40
−50
−50
−60
−70
−80
−90
−60
−70
−80
−90
−100
−100
−110
−110
−120
−120
−130
−130
−140
20
VDD = 3.3 V
PO = 20 mW
RL = 50 Ω
−10
Crosstalk − dB
Crosstalk − dB
−30
VDD = 1.6 V
PO = 4.5 mW
RL = 50 Ω
−140
100
1k
10 k
20 k
20
100
f − Frequency − Hz
Figure 21
1k
f − Frequency − Hz
Figure 22
CLOSED-LOOP GAIN AND PHASE
vs
FREQUENCY
40
180°
Phase
30
150°
120°
90°
10
Gain
60°
0
30°
−10
0°
−20
−30°
−30
−40
−60°
VDD = 1.6 V
RL = 16 Ω
TA = 25°C
−90°
−120°
−50
−60
10
−150°
100
1k
10 k
100 k
1M
10 M
f − Frequency − Hz
Figure 23
10
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
−180°
100 M
Phase
Closed-Loop Gain − dB
20
10 k 20 k
SLOS324B − JUNE 2000 − REVISED SEPTEMBER 2004
TYPICAL CHARACTERISTICS
CLOSED-LOOP GAIN AND PHASE
vs
FREQUENCY
40
180°
Phase
30
150°
120°
90°
10
Gain
60°
0
30°
−10
0°
−20
−30°
−30
−40
−60°
VDD = 1.6 V
RL = 32 Ω
TA = 25°C
−90°
−120°
−50
−60
10
Phase
Closed-Loop Gain − dB
20
−150°
100
1k
10 k
100 k
1M
10 M
−180°
100 M
f − Frequency − Hz
Figure 24
CLOSED-LOOP GAIN AND PHASE
vs
FREQUENCY
40
180°
Phase
30
150°
120°
90°
10
Gain
60°
0
30°
−10
0°
−20
−30°
−30
−40
−60°
VDD = 3.3 V
RL = 16 Ω
TA = 25°C
−90°
−120°
−50
−60
10
Phase
Closed-Loop Gain − dB
20
−150°
100
1k
10 k
100 k
1M
10 M
−180°
100 M
f − Frequency − Hz
Figure 25
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
11
SLOS324B − JUNE 2000 − REVISED SEPTEMBER 2004
TYPICAL CHARACTERISTICS
CLOSED-LOOP GAIN AND PHASE
vs
FREQUENCY
40
180°
Phase
30
150°
120°
90°
10
Gain
60°
0
30°
−10
0°
−20
−30°
−30
−40
Phase
Closed-Loop Gain − dB
20
−60°
VDD = 3.3 V
RL = 32 Ω
TA = 25°C
−90°
−120°
−50
−150°
−60
10
100
1k
10 k
100 k
1M
10 M
−180°
100 M
f − Frequency − Hz
Figure 26
SUPPLY CURRENT
vs
SUPPLY VOLTAGE
POWER DISSIPATION
vs
OUTPUT POWER
40
1
VDD = 3.3 V
VDD Low-to-High
35
PD − Power Dissipation − mW
I DD − Supply Current − mA
0.8
0.6
0.4
0.2
30
25
20
15
10
0
5
−0.2
0
0.4
0.8
1.2
1.6
2
2.4
2.8
3.2
3.6
0
0
10
VDD − Supply Voltage − V
Figure 27
12
20
30
Figure 28
POST OFFICE BOX 655303
40
50
PO − Output Power − mW
• DALLAS, TEXAS 75265
60
70
SLOS324B − JUNE 2000 − REVISED SEPTEMBER 2004
APPLICATION INFORMATION
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 1. RI is set internally and is fixed at 20 kΩ.
fc +
1
2p R I C I
(1)
The value of CI is important to consider, as it directly affects the bass (low frequency) performance of the circuit.
Consider the example where the specification calls for a flat bass response down to 20 Hz. Equation 1 is
reconfigured as equation 2.
CI +
1
2p R I f c
(2)
In this example, CI is 0.40 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. 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/4, which is likely higher than the source dc level. It is important
to confirm the capacitor polarity in the application.
power supply decoupling, CS
The TPA6102A2 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 55-kΩ source inside the amplifier. To keep the start-up pop as low as possible, the relationship
shown in equation 3 should be maintained.
ǒC B
1
v 1
ǒCI RIǓ
55 kΩǓ
(3)
As an example, consider a circuit where CB is 1 µF, CI is 1 µF, and RI is 20 kΩ. Inserting these values into the
equation 3 results in: 18.18 ≤ 50 which satisfies the rule. Bypass capacitor (CB) with values of 0.47-µF to 1-µF
ceramic or tantalum low-ESR capacitors are recommended for the best THD and noise performance.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
13
SLOS324B − JUNE 2000 − REVISED SEPTEMBER 2004
APPLICATION INFORMATION
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 4.
fc +
1
2p R L C C
(4)
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
Ą73 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 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:
ǒC B
1
v 1 Ơ 1
ǒCI RIǓ RLCC
55 kΩǓ
(5)
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.
3.3-V versus 1.6-V operation
The TPA6102A2 was designed for operation over a supply range of 1.6 V to 3.6 V. There are no special
considerations for 1.6-V versus 3.3-V operation as far as supply bypassing, gain setting, or stability. Supply
current is slightly reduced from 0.75 mA (typical) to 0.65 mA (typical). The most important consideration is that
of output power. Each amplifier can produce a maxium output voltage swing within a few hundred millivolts of
the rails with a 10-kΩ load. However, this voltage swing decreases as the load resistance decreases and the
rDS(on) as the output stage transistors becomes more significant. For example, for a 32-Ω load, the maximum
peak output voltage with VDD = 1.6 V is approximately 0.7 V with no clipping distortion. This reduced voltage
swing effectively reduces the maximum undistorted output power.
14
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
SLOS324B − JUNE 2000 − REVISED SEPTEMBER 2004
MECHANICAL DATA
D (R-PDSO-G**)
PLASTIC SMALL-OUTLINE PACKAGE
14 PIN SHOWN
0.050 (1,27)
0.020 (0,51)
0.014 (0,35)
14
0.010 (0,25) M
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°−ā 8°
A
0.044 (1,12)
0.016 (0,40)
Seating Plane
0.069 (1,75) MAX
0.010 (0,25)
0.004 (0,10)
PINS **
0.004 (0,10)
8
14
16
A MAX
0.197
(5,00)
0.344
(8,75)
0.394
(10,00)
A MIN
0.189
(4,80)
0.337
(8,55)
0.386
(9,80)
DIM
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).
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
15
SLOS324B − JUNE 2000 − REVISED SEPTEMBER 2004
MECHANICAL INFORMATION
DGK (R-PDSO-G8)
PLASTIC SMALL-OUTLINE PACKAGE
0,38
0,25
0,65
8
0,25 M
5
0,15 NOM
3,05
2,95
4,98
4,78
Gage Plane
0,25
1
0°−ā 6°
4
3,05
2,95
0,69
0,41
Seating Plane
1,07 MAX
0,15
0,05
0,10
4073329/B 04/98
NOTES: A.
B.
C.
D.
16
All linear dimensions are in millimeters.
This drawing is subject to change without notice.
Body dimensions do not include mold flash or protrusion.
Falls within JEDEC MO-187
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
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 2004, Texas Instruments Incorporated