Texas Instruments | 2-W Filterless Mono Class-D Audio Power Amplifier (Rev. F) | Datasheet | Texas Instruments 2-W Filterless Mono Class-D Audio Power Amplifier (Rev. F) Datasheet

Texas Instruments 2-W Filterless Mono Class-D Audio Power Amplifier (Rev. F) Datasheet
PW
TPA2000D1
GQC
www.ti.com
SLOS328F – JUNE 2000 – REVISED MARCH 2004
2-W FILTERLESS MONO CLASS-D AUDIO POWER AMPLIFIER
FEATURES
•
•
•
•
•
•
•
Modulation Scheme Optimized to Operate
Without a Filter
4 mm × 4 mm MicroStar Junior BGA and
TSSOP Package Options
2 W Into a 4-Ω Speaker (THD+N<1%)
<0.2% THD+N at 1.5 W, 1 kHz, Into a 4-Ω Load
Extremely Efficient Third Generation 5-V
Class-D Technology:
– Low-Supply Current (No Filter): 4 mA
– Low-Supply Current (Filter): 7.5 mA
– Low-Shutdown Current: 0.05 µA
– Low-Noise Floor: 40 µVRMS (No-Weighting
Filter)
– Maximum Efficiency Into 8 Ω, 75 - 85 %
– 4 Internal Gain Settings: 6 to 23.5 dB
– PSRR: -77 dB
Integrated Depop Circuitry
Short-Circuit Protection (Short to Battery,
Ground, and Load)
APPLICATIONS
•
High-Efficiency For Extended Battery Run
Time
PW PACKAGE
(TOP VIEW)
INP
INN
SHUTDOWN
GAIN0
GAIN1
PVDD
OUTP
PGND
1
2
3
4
5
6
7
8
BYPASS
AGND
COSC
ROSC
VDD
PVDD
OUTN
PGND
16
15
14
13
12
11
10
9
MicroStar Junior (GQC) Package
(TOP VIEW)
INP
AGND BYPASS
A2
INN
SHUTDOWN
GAIN0
GAIN1
PVDD
PVDD
OUTP
A6
A1
A7
B1
B7
C1
C7
D1
D7
E1
E7
F1
F7
G1
G7
NC
COSC
ROSC
VDD
PVDD
PVDD
OUTN
PGND
(SIDE VIEW)
NC – No internal connection, still requires a pad for the ball.
NOTE: The shaded terminals are used for thermal
connections to the ground plane.
DESCRIPTION
The TPA2000D1 is a 2-W mono bridge-tied-load (BTL) class-D amplifier designed to drive a speaker with at least
4-Ω impedance. The amplifier uses TI's third generation modulation technique, which results in improved
efficiency and SNR. It also allows the device to be connected directly to the speaker without the use of the LC
output filter commonly associated with class-D amplifiers (this results in EMI that must be shielded at the system
level). These features make the device ideal for use in devices where high efficiency is needed to extend battery
run time.
The gain of the amplifier is controlled by two input terminals, GAIN1 and GAIN0. This allows the amplifier to be
configured for a gain of 6, 12, 18, and 23.5 dB. The differential input terminals are high-impedance CMOS inputs,
and can be used as summing nodes.
The class-D BTL amplifier includes depop circuitry to reduce the amount of turnon pop at power up and when
cycling SHUTDOWN.
The TPA2000D1 is available in the 16-pin TSSOP and MicroStar Junior™ BGA packages that drive 2 W of
continuous output power into a 4-Ω load. TPA2000D1 operates over an ambient temperature range of -40°C to
85°C.
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.
MicroStar Junior 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 © 2000–2004, Texas Instruments Incorporated
TPA2000D1
www.ti.com
SLOS328F – JUNE 2000 – REVISED MARCH 2004
This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated
circuits be handled with appropriate precautions. Failure to observe proper handling and installation
procedures can cause damage.
ESD damage can range from subtle performance degradation to complete device failure. Precision
integrated circuits may be more susceptible to damage because very small parametric changes could
cause the device not to meet its published specifications.
AVAILABLE OPTIONS
PACKAGED DEVICES
TA
40°C to 85°C
(1)
(2)
TSSOP (PW) (1)
GQC (2)
TPA2000D1PW
TPA2000D1GQCR
The PW package is available taped and reeled. To order a taped
and reeled part, add the suffix R to the part number (e.g.,
TPA2000D1PWR).
The GQC package is only available taped and reeled.
FUNCTIONAL BLOCK DIAGRAM
VDD
AGND
VDD
Gain
Adjust
INN
PVDD
_
+
_
Deglitch
Logic
Gate
Drive
OUTN
+
_
+
PGND
+
_
PVDD
+
Gain
Adjust
INP
_
_
+
Deglitch
Logic
Gate
Drive
OUTP
PGND
SHUTDOWN
GAIN1
GAIN0
COSC
ROSC
BYPASS
2
Gain
2
Biases
and
References
Ramp
Generator
Start-Up
Protection
Logic
Thermal
VDD ok
OC
Detect
TPA2000D1
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SLOS328F – JUNE 2000 – REVISED MARCH 2004
TERMINAL FUNCTIONS
TERMINAL
NAME
NO.
I/O
DESCRIPTION
GQC
PW
A3 - A5,
B2 - B6
C2 - C6
D2 - D4
15
I
Analog ground
BYPASS
A6
16
I
Connect capacitor to ground for BYPASS voltage filtering.
COSC
B7
14
I
Connect capacitor to ground to set oscillation frequency.
GAIN0
C1
4
I
Bit 0 of gain control (TTL logic level)
GAIN1
D1
5
I
Bit 1 of gain control (TTL logic level)
INN
A1
2
I
Negative differential input
INP
A2
1
I
Positive differential input
OUTN
G7
10
O
Negative BTL output
OUTP
G1
7
O
Positive BTL output
PGND
D5, D6
E2 - E6
F2 - F6
G2 - G6
8, 9
I
High-current grounds
PVDD
E1, E7,
F1, F7
6, 11
I
High-current power supplies
ROSC
C7
13
I
Connect resistor to ground to set oscillation frequency.
SHUTDOWN
B1
3
I
Places the amplifier in shutdown mode if a TTL logic low is placed on this terminal, and
normal operation if a TTL logic high is placed on this terminal.
VDD
D7
12
I
Analog power supply
AGND
ABSOLUTE MAXIMUM RATINGS
over operating free-air temperature range (unless otherwise noted) (1)
UNITS
Supply voltage
VDD, PVDD
-0.3 V to 5.5 V
Input voltage, VI
-0.3 V to VDD +0.3 V
Continuous total power dissipation
(See Dissipation Rating Table)
Operating free-air temperature range, TA
-40°C to 85°C
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
(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
TA ≤ 25°C
DERATING FACTOR
TA = 70°C
TA = 85°C
PW
774 mW
6.19 mW/°C
495 mW
402 mW
GQC
2.61 W
20.9 mW/°C
1.67 W
1.36 W
3
TPA2000D1
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SLOS328F – JUNE 2000 – REVISED MARCH 2004
RECOMMENDED OPERATING CONDITIONS
MIN
MAX
2.7
5.5
UNIT
VDD, PVDD
Supply voltage
VIH
High-level input voltage
GAIN0, GAIN1, SHUTDOWN
VIL
Low-level input voltage
GAIN0, GAIN1, SHUTDOWN
0.7
V
fs
Switching frequency
200
300
kHz
TA
Operating free-air temperature
-40
85
°C
2
V
V
ELECTRICAL CHARACTERISTICS
at specified free-air temperature, PVDD = VDD = 5 V, TA = 25°C (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
25
mV
|VOS|
Output offset voltage (measured differentially)
VI = 0 V,
PSRR
Power supply rejection ratio
PVDD = 4.9 V to 5.1 V
|IIH|
High-level input current
PVDD = 5.5,
VI = PVDD
1
µA
|IIL|
Low-level input current
PVDD = 5.5,
VI = 0 V
1
µA
IDD
Supply current, no filter (with or without
speaker load)
4
6
mA
IDD(SD)
Supply current, shutdown mode
0.05
20
µA
MAX
UNIT
AV = any gain
-77
GAIN0, GAIN1, SHUTDOWN = 0 V
dB
OPERATING CHARACTERISTICS
PVDD = VDD = 5 V, TA = 25°C, RL = 4 Ω, gain = 6 dB (unless otherwise noted)
PARAMETER
TEST CONDITIONS
PO
Output power
THD = 1%,
f = 1 kHz,
THD + N
Total harmonic distortion plus noise
PO = 1.5 W,
f = 20 Hz to 20 kHz
kSVR
Supply ripple rejection ratio
f = 1 kHz,
CBYP = 1 µF
SNR
Signal-to-noise ratio
Vn
Output noise voltage (no-noise
weighting filter)
Zi
Input impedance
CBYP = 1 µF,
MIN
TYP
2
W
<0.2%
-67
dB
95
dB
40
µV(rms)
>15
kΩ
f = < 10 Hz to 22
kHz
ELECTRICAL CHARACTERISTICS
at specified free-air temperature, PVDD = VDD = 3.3 V, TA = 25°C (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
|VOS|
Output offset voltage (measured
differentially)
VI = 0 V
PSRR
Power supply rejection ratio
PVDD = 3.2 V
to 3.4 V
|IIH|
High-level input current
PVDD = 3.3
VI = PVDD
1
µA
|IIL|
Low-level input current
PVDD = 3.3
VI = 0 V
1
µA
IDD
Supply current, no filter (with or without
speaker load)
4
6
mA
IDD(SD)
Supply current, shutdown mode
0.05
20
µA
4
AV = any gain
25
-61
mV
dB
TPA2000D1
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SLOS328F – JUNE 2000 – REVISED MARCH 2004
OPERATING CHARACTERISTICS
PVDD = VDD = 3.3 V, TA = 25°C, RL = 4 Ω, gain = 6 dB (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
PO
Output power
THD = 1%,
f = 1 kHz
THD + N
Total harmonic distortion plus noise
PO = 55 mW,
f = 20 Hz to 20 kHz
kSVR
Supply ripple rejection ratio
f = 1 kHz,
CBYP = 1 µF
SNR
Signal-to-noise ratio
Vn
Output noise voltage (no-noise
weighting filter)
Zi
Input impedance
CBYP= 1 µF,
TYP
850
f = <10 Hz to 22 kHz
MAX
UNIT
mW
<0.2%
-61
dB
93
dB
40
µV(rms)
>15
kΩ
Table 1. GAIN SETTINGS
AMPLIFIER GAIN
(dB)
INPUT IMPEDANCE
(kΩ)
TYP
TYP
6
104
12
74
0
18
44
1
23.5
24
GAIN1
GAIN0
0
0
0
1
1
1
5
TPA2000D1
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SLOS328F – JUNE 2000 – REVISED MARCH 2004
TYPICAL CHARACTERISTICS
TABLE OF GRAPHS
FIGURE
η
Efficiency
vs Output power
1
FFT at 1.5-W output power
vs Frequency
2
THD+N
Total harmonic distortion plus noise
k(SRR)
Supply ripple rejection ratio
vs Output power
3, 4, 5
vs Frequency
6, 7
vs Frequency
8
TEST SETUP FOR GRAPHS
The THD+N measurements shown do not use an LC output filter, but do use a 100-Ω, 0.047-µF RC low-pass
filter with a cutoff frequency of ~30 kHz before the audio analyzer so the switching frequency does not dominate
the measurement. This is done to ensure that the THD+N measured is just the audible THD+N. The THD+N
measurements are shown at the highest gain for worst case. The efficiency was measured with no filters, and a
3-Ω, 4-Ω, or 8-Ω resistor in series with a 33-µH inductor as the load.
EFFICIENCY
vs
OUTPUT POWER
100
RL = 8 Ω, 33 µH
RL = 4 Ω, 33 µH
90
80
RL = 3 Ω, 33 µH
Efficiency − %
70
60
50
Class-AB,
RL = 4 Ω
40
30
20
10
0
0
0.5
2.5
1
1.5
2
PO − Output Power − W
Figure 1.
6
3
3.5
TPA2000D1
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SLOS328F – JUNE 2000 – REVISED MARCH 2004
TYPICAL CHARACTERISTICS (continued)
FFT AT 1.5-W OUTPUT POWER
vs
FREQUENCY
+10
VDD = 5 V,
RL = 4 Ω,
f = 1 kHz,
PO = 1.5 W
−10
Power − VdB
−30
−50
−70
−90
−110
−130
−150
0
4k
8k
12 k
f − Frequency − Hz
16 k
20 k
24 k
Figure 2.
TOTAL HARMONIC DISTORTION PLUS NOISE
vs
OUTPUT POWER
10
2
THD+N − Total Harmonic Distortion Plus Noise − %
THD+N − Total Harmonic Distortion Plus Noise − %
TOTAL HARMONIC DISTORTION PLUS NOISE
vs
OUTPUT POWER
VDD = 5 V,
Gain = 23.5,
RL = 3 Ω
1
f = 1 kHz
0.2
0.1
f = 20 Hz
0.02
0.01
0.01
10 m
f = 20 kHz
10
2
VDD = 5 V,
Gain = 23.5,
RL = 4 Ω
1
f = 1 kHz
0.2
0.1
f = 20 Hz
0.02
0.01
f = 20 kHz
0.001
10 m
PO − Output Power − W
100 m 200 m
PO − Output Power − W
Figure 3.
Figure 4.
100 m 200 m
1
3
1
3
7
TPA2000D1
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SLOS328F – JUNE 2000 – REVISED MARCH 2004
TYPICAL CHARACTERISTICS (continued)
THD+N − Total Harmonic Distortion Plus Noise − %
10
VDD = 5 V,
Gain = 23.5,
RL = 8 Ω
2
1
0.2
f = 1 kHz
0.1
f = 20 Hz
0.02
0.01
f = 20 kHz
0.001
10 m
100 m 200 m
1
3
1
VDD = 5 V,
f = 1 kHz,
RL = 4 Ω
0.2
0.1
PO = 1.5 W
0.02
0.01
PO = 0.75 W
PO = 2 W
0.001
20
100 200
1k
2k
10 k
PO − Output Power − W
f − Frequency − Hz
Figure 5.
Figure 6.
TOTAL HARMONIC DISTORTION PLUS NOISE
vs
FREQUENCY
SUPPLY RIPPLE REJECTION RATIO
vs
FREQUENCY
1
20 k
−40
VDD = 5 V,
f = 1 kHz,
RL = 8 Ω
0.2
PO = 0.1 W
0.1
0.02
0.01
PO = 1 W
PO = 0.5 W
0.001
−45
−50
−55
−60
−65
−70
−75
−80
20
8
TOTAL HARMONIC DISTORTION PLUS NOISE
vs
FREQUENCY
K(SVR) − Supply Ripple Rejection Ratio − dB
THD+N − Total Harmonic Distortion Plus Noise − %
THD+N − Total Harmonic Distortion Plus Noise − %
TOTAL HARMONIC DISTORTION PLUS NOISE
vs
OUTPUT POWER
100 200
1k
2k
10 k 20 k
10
100 200
1k 2k
f − Frequency − Hz
f − Frequency −Hz
Figure 7.
Figure 8.
10 k 20 k
TPA2000D1
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SLOS328F – JUNE 2000 – REVISED MARCH 2004
APPLICATION INFORMATION
ELIMINATING THE OUTPUT FILTER WITH THE TPA2000D1
This section explains why the user can eliminate the output filter with the TPA2000D1.
EFFECT ON AUDIO
The class-D amplifier outputs a pulse-width modulated (PWM) square wave, which is the sum of the switching
waveform and the amplified input audio signal. The human ear acts as a band-pass filter such that only the
frequencies between approximately 20 Hz and 20 kHz are passed. The switching frequency components are
much greater than 20 kHz, so the only signal heard is the amplified input audio signal.
TRADITIONAL CLASS-D MODULATION SCHEME
The traditional class-D modulation scheme, which is used in the TPA005Dxx family, has a differential output
where each output is 180 degrees out of phase and changes from ground to the supply voltage, VDD. Therefore,
the differential prefiltered output varies between positive and negative VDD, where filtered 50% duty cycle yields
0 V across the load. The traditional class-D modulation scheme with voltage and current waveforms is shown in
Figure 9. Even at an average of 0 V across the load (50% duty cycle), the current to the load is high, causing
high loss, and a high supply current.
OUTP
OUTN
+5 V
Differential Voltage
Across Load
OV
–5 V
Current
Figure 9. Traditional Class-D Modulation Scheme Output Voltage and Current Waveforms Into an
Inductive Load With No Input
TPA2000D1 MODULATION SCHEME
The TPA2000D1 uses a modulation scheme that still has each output switching from 0 to the supply voltage.
However, OUTP and OUTN are now in phase with each other with no input. The duty cycle of OUTP is greater
than 50% and OUTN is less than 50% for positive voltages. The duty cycle of OUTP is less than 50% and OUTN
is greater than 50% for negative voltages. The voltage across the load sits at 0 V throughout most of the
switching period greatly reducing the switching current, which reduces any I2R losses in the load.
9
TPA2000D1
SLOS328F – JUNE 2000 – REVISED MARCH 2004
www.ti.com
APPLICATION INFORMATION (continued)
OUTP
OUTN
Differential
Voltage
Across
Load
Output = 0 V
+5 V
0V
–5 V
Current
OUTP
OUTN
Differential
+5 V
Voltage
Across
0V
Load
Output > 0 V
–5 V
Current
Figure 10. The TPA2000D1 Output Voltage and Current Waveforms Into an Inductive Load
EFFICIENCY: WHY YOU MUST USE A FILTER WITH THE TRADITIONAL CLASS-D MODULATION
SCHEME
The main reason that the traditional class-D amplifier needs an output filter is that the switching waveform results
in maximum current flow. This causes more loss in the load, which causes lower efficiency. The ripple current is
large for the traditional modulation scheme because the ripple current is proportional to voltage multiplied by the
time at that voltage. The differential voltage swing is 2 × VDD and the time at each voltage is half the period for
the traditional modulation scheme. An ideal LC filter is needed to store the ripple current from each half cycle for
the next half cycle, while any resistance causes power dissipation. The speaker is both resistive and reactive,
whereas an LC filter is almost purely reactive.
The TPA2000D1 modulation scheme has little loss in the load without a filter because the pulses are short and
the change in voltage is VDD instead of 2 × VDD. As the output power increases, the pulses widen making the
ripple current larger. Ripple current could be filtered with an LC filter for increased efficiency, but for most
applications the filter is not needed.
An LC filter with a cutoff frequency less than the class-D switching frequency allows the switching current to flow
through the filter instead of the load. The filter has less resistance than the speaker that results in less power
dissipated, which increases efficiency.
10
TPA2000D1
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SLOS328F – JUNE 2000 – REVISED MARCH 2004
APPLICATION INFORMATION (continued)
EFFECTS OF APPLYING A SQUARE WAVE INTO A SPEAKER
Audio specialists advise not to apply a square wave to speakers. If the amplitude of the waveform is high enough
and the frequency of the square wave is within the bandwidth of the speaker, the square wave could cause the
voice coil to jump out of the air gap and/or scar the voice coil. A 250-kHz switching frequency, however, is not
significant because the speaker cone movement is proportional to 1/f2 for frequencies beyond the audio band.
Therefore, the amount of cone movement at the switching frequency is very small. However, damage could
occur to the speaker if the voice coil is not designed to handle the additional power. To size the speaker for
added power, the ripple current dissipated in the load needs to be calculated by subtracting the theoretical
supplied power (PSUP THEORETICAL) from the actual supply power (PSUP) at maximum output power (POUT). The
switching power dissipated in the speaker is the inverse of the measured efficiency (ηMEASURED) minus the
theoretical efficiency (ηTHEORETICAL) all multiplied by POUT.
PSPKR = PSUP – PSUP THEORETICAL (at max output power)
(1)
PSPKR = POUT(PSUP / POUT – PSUP THEORETICAL / POUT) (at max output power)
(2)
PSPKR = POUT(1/ηMEASURED – 1/ηTHEORETICAL) (at max output power)
(3)
The maximum efficiency of the TPA2000D1 with an 8-Ω load is 85%. Using Equation 3 with the efficiency at
maximum power (78%), we see that there is an additional 106 mW dissipated in the speaker. The added power
dissipated in the speaker is not an issue as long as it is taken into account when choosing the speaker.
WHEN TO USE AN OUTPUT FILTER
Design the TPA2000D1 without the filter if the traces from amplifier to speaker are short. The TPA2000D1
passed FCC and CE radiated emissions with no shielding with speaker wires eight inches long or less. Notebook
PCs and powered speakers where the speaker is in the same enclosure as the amplifier are good applications
for class-D without a filter.
A ferrite bead filter (shown in Figure 11) can often be used if the design is failing radiated emissions without a
filter, and the frequency sensitive circuit is greater than 1 MHz. This is good for circuits that just have to pass
FCC and CE because FCC and CE only test radiated emissions greater than 30 MHz. If choosing a ferrite bead,
choose one with high impedance at high frequencies, but low impedance at low frequencies.
Use an LC output filter if there are low frequency (<1 MHz) EMI sensitive circuits and/or there are long leads
from amplifier to speaker.
The LC output filter is shown in Figure 11.
• L1 = L2 = 22 µH (DCR = 110 mΩ, part number = SCD0703T-220 M-S, manufacturer = GCI)
• C1 = C2 = 1 µF
The ferrite filter is shown in Figure 11, where L is a ferrite bead.
• L1 = L2 = ferrite bead (part number = MPZ1608S221, manufacturer = TDK)
• C1 = C2 = 1 nF
L1
OUT+
C1
OUT–
L2
C2
Figure 11. Class-D Output Filter
11
TPA2000D1
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SLOS328F – JUNE 2000 – REVISED MARCH 2004
APPLICATION INFORMATION (continued)
GAIN SETTING VIA GAIN0 AND GAIN1 INPUTS
The gain of the TPA2000D1 is set by two input terminals, GAIN0 and GAIN1.
The gains listed in Table 1 are realized by changing the taps on the input resistors inside the amplifier. This
causes the input impedance (Zi) to be dependent on the gain setting. The actual gain settings are controlled by
ratios of resistors, so the actual gain distribution from part-to-part is quite good. However, the input impedance
can shift by up to 30% due to shifts in the actual resistance of the input resistors.
For design purposes, the input network (discussed in the next section) should be designed assuming an input
impedance of 20 kΩ, which is the absolute minimum input impedance of the TPA2000D1. At the higher gain
settings, the input impedance can increase as high as 115 kΩ.
Table 2. GAIN SETTINGS
AMPLIFIER GAIN
(dB)
INPUT IMPEDANCE
(kΩ)
TYP
TYP
6
104
1
12
74
0
18
44
1
23.5
24
GAIN1
GAIN0
0
0
0
1
1
INPUT RESISTANCE
Each gain setting is achieved by varying the input resistance of the amplifier, which can range from its smallest
value to over six times that value. As a result, if a single capacitor is used in the input high-pass filter, the -3 dB
or cutoff frequency also changes by over six times.
Zf
Ci
Input
Signal
IN
The -3-dB frequency can be calculated using Equation 4.
1
f 3 dB 2 CiZ i
12
Zi
(4)
TPA2000D1
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SLOS328F – JUNE 2000 – REVISED MARCH 2004
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 the input impedance of the amplifier (Zi) form a
high-pass filter with the corner frequency determined in Equation 5.
−3 dB
fc 1
2 Zi C i
fc
(5)
The value of Ci is important because it directly affects the bass (low frequency) performance of the circuit.
Consider the example where Zi is 20 kΩ and the specification calls for a flat bass response down to 80 Hz.
Equation 5 is reconfigured as Equation 6.
1
Ci 2 Z i f c
(6)
In this example, Ci is 0.1 µF, so one would likely choose a value in the range of 0.1 µF to 1 µF. If the gain is
known and constant, use Zi from Table 1 to calculate Ci. A further consideration for this capacitor is the leakage
path from the input source through the input network (Ci) and the feedback network 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. 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. It is important to
confirm the capacitor polarity in the application.
Ci must be 10 times smaller than the bypass capacitor to reduce clicking and popping noise from power on/off
and entering and leaving shutdown. After sizing Ci for a given cutoff frequency, size the bypass capacitor to 10
times that of the input capacitor.
C
C i BYP
10
(7)
POWER SUPPLY DECOUPLING, CS
The TPA2000D1 is a high-performance CMOS audio amplifier that requires adequate power supply decoupling
to ensure 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 audio
power amplifier is recommended.
MIDRAIL BYPASS CAPACITOR, CBYP
The midrail bypass capacitor (CBYP) is the most critical capacitor and serves several important functions. During
start-up or recovery from shutdown mode, CBYP determines the rate at which the amplifier starts up. 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, which appears as degraded PSRR and
THD+N.
Bypass capacitor (CBYP) values of 0.47-µF to 1-µF ceramic or tantalum low-ESR capacitors are recommended for
the best THD and noise performance.
13
TPA2000D1
SLOS328F – JUNE 2000 – REVISED MARCH 2004
www.ti.com
Increasing the bypass capacitor reduces clicking and popping noise from power on/off and entering and leaving
shutdown. To have minimal pop, CBYP should be 10 times larger than Ci.
C BYP 10 C i
(8)
DIFFERENTIAL INPUT
The differential input stage of the amplifier cancels any noise that appears on both input lines of the channel. To
use the TPA2000D1 EVM with a differential source, connect the positive lead of the audio source to the INP
input and the negative lead from the audio source to the INN input. To use the TPA2000D1 with a single-ended
source, ac ground the INN input through a capacitor and apply the audio single to the input. In a single-ended
input application, the INN input should be ac-grounded at the audio source instead of at the device input for best
noise performance.
SHUTDOWN MODES
The TPA2000D1 employs a shutdown mode of operation designed to reduce supply current (IDD) to the absolute
minimum level during periods of nonuse for battery-power conservation. The SHUTDOWN input terminal should
be held high during normal operation when the amplifier is in use. Pulling SHUTDOWN low causes the outputs to
mute and the amplifier to enter a low-current state, IDD(SD) = 1 µA. SHUTDOWN should never be left
unconnected because amplifier operation would be unpredictable.
USING LOW-ESR CAPACITORS
Low-ESR capacitors are recommended throughout this application section. A real (as opposed to ideal) 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.
14
TPA2000D1
www.ti.com
SLOS328F – JUNE 2000 – REVISED MARCH 2004
SWITCHING FREQUENCY
The switching frequency is determined using the values of the components connected to ROSC (pin 13) and
COSC (pin 14) and are calculated using Equation 9.
6.6
fs ROSC COSC
(9)
The switching frequency was chosen to be centered on 250 kHz. This frequency represents the optimization of
audio fidelity due to oversampling and the maximization of efficiency by minimizing the switching losses of the
amplifier.
The recommended values are a resistance of 120 kΩ and a capacitance of 220 pF. Using these component
values, the amplifier operates properly by using 5% tolerance resistors and 10% tolerance capacitors. The
tolerance of the components can be changed as long as the switching frequency remains between 200 kHz and
300 kHz. Within this range, the internal circuitry of the device provides stable operation.
APPLICATION CIRCUIT
TPA2000D1
C2
Audio Input–
C3
Audio Input+
1 µF
1 µF
To System
Controller
1 INP
2
BYPASS
INN
AGND
16
15
C7
1 µF
C1
3 SHUTDOWN
COSC
14
Gain Select
4 GAIN0
13 220 pF
Gain Select
5
6
VDD
C8
10 µF
C4
1 µF
7
8
GAIN1
ROSC
VDD
PVDD
PVDD
OUTP
OUTN
PGND
PGND
12
11
R1
120 kΩ
C6
1 µF
VDD
OUT–
10
9
VDD
C5
1 µF
OUT+
Table 3. TPA2000D1 APPLICATION CIRCUIT BILL OF MATERIALS
SIZE
QUANTITY
MANUFACTURER
C1
REFERENCE
Capacitor, ceramic, 220 pF, ±10%, XICON, 50 V
DESCRIPTION
0805
1
Mouser
140-CC501B221K
PART NUMBER
C2 - C7
Capacitor, ceramic, 1 µF, +80%/-20%, Y5V, 16 V
0805
6
Murata
GRM40-Y5V105Z16
C8
Capacitor, ceramic, 10 µF, +80%/-20%, Y5V, 16 V
1210
1
Murata
GRM235-Y5V106Z16
R1
Resistor, chip, 120 kΩ, 1/10 W, 5%, XICON
0805
1
Mouser
260-120K
U1
IC, TPA2000D1, audio power amplifier, 2-W, single
channel, class-D
24-pin
TSSOP
1
TI
TPA2000D1PW
15
TPA2000D1
www.ti.com
SLOS328F – JUNE 2000 – REVISED MARCH 2004
LOW SUPPLY VOLTAGE POP
The TPA2000D1 pops when coming out of shutdown at low supply voltages (3.3 V and less) when using the
application schematic shown above. The pops occur because the common-mode input range is worse at the
lower supply voltages. At low supply voltages, the inputs are not within the common-mode input range when
coming out of shutdown. The outputs develop an offset voltage until the inputs settle within the common-mode
input range. This causes a pop. Figure 12 shows 1-MΩ resistors added to form voltage dividers. The voltage
dividers bias the inputs to VDD/2 that keeps the pop low at turn on and when coming out of shutdown. The
resistors should be 1% tolerance to ensure the offset voltage is not increased.
VDD
1 M
+
1 M
Audio In
1 M
INP
INN
TPA2000D1
−
1 M
VDD
Figure 12. Voltage Dividers
16
PACKAGE OPTION ADDENDUM
www.ti.com
30-Nov-2017
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
Lead/Ball Finish
MSL Peak Temp
(2)
(6)
(3)
Op Temp (°C)
Device Marking
(4/5)
TPA2000D1PW
ACTIVE
TSSOP
PW
16
90
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
-40 to 85
2000D1
TPA2000D1PWG4
ACTIVE
TSSOP
PW
16
90
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
-40 to 85
2000D1
TPA2000D1PWR
ACTIVE
TSSOP
PW
16
2000
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
-40 to 85
2000D1
TPA2000D1PWRG4
ACTIVE
TSSOP
PW
16
2000
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
-40 to 85
2000D1
(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)
RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of <=1000ppm threshold. Antimony trioxide based
flame retardants must also meet the <=1000ppm threshold requirement.
(3)
MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4)
There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.
(5)
Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation
of the previous line and the two combined represent the entire Device Marking for that device.
(6)
Lead/Ball Finish - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead/Ball Finish values may wrap to two lines if the finish
value exceeds the maximum column width.
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
Addendum-Page 1
Samples
PACKAGE OPTION ADDENDUM
www.ti.com
30-Nov-2017
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.
OTHER QUALIFIED VERSIONS OF TPA2000D1 :
• Automotive: TPA2000D1-Q1
NOTE: Qualified Version Definitions:
• Automotive - Q100 devices qualified for high-reliability automotive applications targeting zero defects
Addendum-Page 2
PACKAGE MATERIALS INFORMATION
www.ti.com
14-Nov-2017
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
TPA2000D1PWR
Package Package Pins
Type Drawing
TSSOP
PW
16
SPQ
Reel
Reel
A0
Diameter Width (mm)
(mm) W1 (mm)
2000
330.0
12.4
Pack Materials-Page 1
6.9
B0
(mm)
K0
(mm)
P1
(mm)
5.6
1.6
8.0
W
Pin1
(mm) Quadrant
12.0
Q1
PACKAGE MATERIALS INFORMATION
www.ti.com
14-Nov-2017
*All dimensions are nominal
Device
Package Type
Package Drawing
Pins
SPQ
Length (mm)
Width (mm)
Height (mm)
TPA2000D1PWR
TSSOP
PW
16
2000
367.0
367.0
35.0
Pack Materials-Page 2
PACKAGE OUTLINE
PW0016A
TSSOP - 1.2 mm max height
SCALE 2.500
SMALL OUTLINE PACKAGE
SEATING
PLANE
C
6.6
TYP
6.2
A
0.1 C
PIN 1 INDEX AREA
14X 0.65
16
1
2X
5.1
4.9
NOTE 3
4.55
8
9
B
0.30
0.19
0.1
C A B
16X
4.5
4.3
NOTE 4
1.2 MAX
(0.15) TYP
SEE DETAIL A
0.25
GAGE PLANE
0.15
0.05
0 -8
0.75
0.50
DETAIL A
A 20
TYPICAL
4220204/A 02/2017
NOTES:
1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing
per ASME Y14.5M.
2. This drawing is subject to change without notice.
3. This dimension does not include mold flash, protrusions, or gate burrs. Mold flash, protrusions, or gate burrs shall not
exceed 0.15 mm per side.
4. This dimension does not include interlead flash. Interlead flash shall not exceed 0.25 mm per side.
5. Reference JEDEC registration MO-153.
www.ti.com
EXAMPLE BOARD LAYOUT
PW0016A
TSSOP - 1.2 mm max height
SMALL OUTLINE PACKAGE
SYMM
16X (1.5)
(R0.05) TYP
1
16
16X (0.45)
SYMM
14X (0.65)
8
9
(5.8)
LAND PATTERN EXAMPLE
EXPOSED METAL SHOWN
SCALE: 10X
SOLDER MASK
OPENING
METAL UNDER
SOLDER MASK
METAL
SOLDER MASK
OPENING
EXPOSED METAL
EXPOSED METAL
0.05 MAX
ALL AROUND
NON-SOLDER MASK
DEFINED
(PREFERRED)
0.05 MIN
ALL AROUND
SOLDER MASK
DEFINED
SOLDER MASK DETAILS
15.000
4220204/A 02/2017
NOTES: (continued)
6. Publication IPC-7351 may have alternate designs.
7. Solder mask tolerances between and around signal pads can vary based on board fabrication site.
www.ti.com
EXAMPLE STENCIL DESIGN
PW0016A
TSSOP - 1.2 mm max height
SMALL OUTLINE PACKAGE
16X (1.5)
SYMM
(R0.05) TYP
1
16X (0.45)
16
SYMM
14X (0.65)
8
9
(5.8)
SOLDER PASTE EXAMPLE
BASED ON 0.125 mm THICK STENCIL
SCALE: 10X
4220204/A 02/2017
NOTES: (continued)
8. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate
design recommendations.
9. Board assembly site may have different recommendations for stencil design.
www.ti.com
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