MAX98314 [MAXIM]
Mono 3.2W Class D Amplifier with Integrated Input Coupling Capacitors; 3.2W单声道D类放大器，集成输入耦合电容
| 型号： | MAX98314 |
| 厂家： | 
MAXIM INTEGRATED PRODUCTS |
| 描述： | Mono 3.2W Class D Amplifier with Integrated Input Coupling Capacitors |
| 文件： | 总14页 (文件大小：2229K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
19-6124; Rev 0; 11/11
E V A L U A T I O N K I T A V A I L A B L E
General Description
Features
The MAX98314 mono 3.2W Class D amplifier provides
Class AB audio performance with Class D efficiency.
This device offers five selectable gain settings (0dB,
3dB, 6dB, 9dB, and 12dB) set by a single gain-select
input (GAIN).
S Integrated Input Coupling Capacitors with
Excellent Linearity
f = 100Hz (6dB)
C
f = 200Hz (12dB)
C
S Low Quiescent Current
0.95mA at 3.7V
Active emissions limiting (AEL) edge rate and overshoot
control circuitry and a filterless spread-spectrum modu-
lation (SSM) scheme greatly reduce EMI and eliminate
the need for output filtering found in traditional Class D
devices.
1.2mA at 5.0V
S Delivers High Output Power at 10% THD+N
3.2W into 4I, V
960mW into 8I, V
= 5V
PVDD
= 3.7V
PVDD
The IC’s low 0.95mA at 3.7V, 1.2mA at 5.0V quiescent
current extends battery life in portable applications.
S Ultra-Low Noise: 19µV
S Eliminates Output Filtering Requirement
Highly linear, integrated input coupling capacitors (C )
IN
Spread Spectrum and Active Emissions Limiting
reduce solution size and provide excellent THD+N, PSRR,
and CMRR performance at low frequencies vs. standard
Class D amplifiers using external input capacitors.
S Click-and-Pop Suppression
S Thermal and Overcurrent Protection
S Low Current Shutdown Mode
S Small, Space-Saving Package
The IC is available in a small 9-bump, 0.3mm pitch WLP
(1.0mm x 1.0mm x 0.80mm) package and is specified
over the -40NC to +85NC extended temperature range.
Applications
Simplified Block Diagram
Mobile Phones
Portable Audio
Notebook Computers
MP3 Players
MAX98314
C
C
IN
CLASS D
MODULATOR
AND H-BRIDGE
Netbook Computers
VoIP Phones
IN
GAIN CONTROL
Ordering Information appears at end of data sheet.
For related parts and recommended products to use with this part, refer to: www.maxim-ic.com/MAX98314.related
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1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
MAX98314
Mono 3.2W Class D Amplifier
with Integrated Input Coupling Capacitors
Functional Diagram/Typical Application Circuit
2.5V TO 5.5V
0.1µF
10µF*
PVDD
A3
SHDN C1
UVLO/POWER
MANAGEMENT
CLICK-AND-POP
SUPPRESSION
PVDD
MAX98314
A1 OUT-
GAIN B3
IN+
LOW-EMI
DRIVER
C3
C2
PGND
CLASS D
MODULATOR
PVDD
IN-
A2 OUT+
LOW-EMI
DRIVER
PGND
B1
PGND
*SYSTEM BULK CAPACITANCE.
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2
MAX98314
Mono 3.2W Class D Amplifier
with Integrated Input Coupling Capacitors
ABSOLUTE MAXIMUM RATINGS
PVDD, IN+, IN-, SHDN, GAIN to PGND...................0.3V to +6V
OUT+, OUT- to PGND............................0.3V to (V + 0.3V)
Continuous Current In/Out of PVDD, PGND, OUT_.........750mA
Continuous Input Current (all other pins)........................ Q20mA
Duration of Short Circuit Between
OUT_ to PVDD, PGND ..........................................Continuous
Between OUT+ and OUT- Pins.............................Continuous
Continuous Power Dissipation (T = +70NC) for Multilayer Board
A
WLP (derate 10.64mW/NC above +70NC).....................851mW
Junction Temperature .....................................................+150NC
Operating Temperature Range.......................... -40NC to +85NC
Storage Temperature Range............................ -65NC to +150NC
Soldering Temperature (reflow) ......................................+260NC
PVDD
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional opera-
tion of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect device reliability.
PACKAGE THERMAL CHARACTERISTICS (Note 1)
WLP
Junction-to-Ambient Thermal Resistance (B ) ........102NC/W
JA
Junction-to-Case Thermal Resistance (B )...............47NC/W
JC
Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-
layer board. For detailed information on package thermal considerations, refer to www.maxim-ic.com/thermal-tutorial.
ELECTRICAL CHARACTERISTICS
(V
= V
= V
= 5V, V
= 0V, A = 6dB (GAIN = PVDD), R = J, R connected between OUT+ to OUT-, AC measure-
PVDD
SHDN
GAIN
PGND V L L
ment bandwidth 20Hz to 22kHz, T = T
to T
, unless otherwise noted. Typical values are at T = +25NC.) (Note 2, 3)
A
MIN
MAX A
PARAMETER
AMPLIFIER CHARACTERISTICS
Supply Voltage Range
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
V
Guaranteed by PSRR test
PVDD falling
2.5
5.5
2.2
1.8
V
V
PVDD
Undervoltage Lockout
UVLO
1.8
1.2
V
V
V
= 5V
PVDD
PVDD
SHDN
Quiescent Current
I
mA
PVDD
= 3.7V
0.95
< 0.1
Shutdown Supply Current
Turn-On Time
10
10
FA
ms
V
I
= 0V, T = +25NC
SHDN
A
t
3.7
ON
Bias Voltage
V
V
/2
BIAS
PVDD
12
GAIN connected to PGND
11.75
8.75
5.75
2.75
-0.25
12.25
9.25
GAIN connected to PGND
through 100kI Q5% resistor
9
6
3
GAIN connected to PVDD
6.25
Voltage Gain
A
f = 1kHz
dB
V
GAIN connected to PVDD
through 100kI Q5% resistor
3.25
GAIN unconnected
0
0.011
199
139
100
70
+0.25
Input Capacitance
C
All gains
FF
IN
A
A
A
A
A
= 12dB
= 9dB
= 6dB
= 3dB
= 0dB
V
V
V
V
V
Highpass Corner Frequency
f
-3dB down
63
189
Hz
C
50
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3
MAX98314
Mono 3.2W Class D Amplifier
with Integrated Input Coupling Capacitors
ELECTRICAL CHARACTERISTICS (continued)
(V
= V
= V
= 5V, V
= 0V, A = 6dB (GAIN = PVDD), R = J, R connected between OUT+ to OUT-, AC measure-
PVDD
SHDN
GAIN
PGND V L L
ment bandwidth 20Hz to 22kHz, T = T
to T
, unless otherwise noted. Typical values are at T = +25NC.) (Note 2, 3)
A
MIN
MAX A
PARAMETER
Common-Mode Rejection Ratio
Output Offset Voltage
SYMBOL
CONDITIONS
= 1kHz, input referred
= +25NC (Note 4)
A
MIN
TYP
67
MAX
UNITS
dB
CMRR
f
IN
V
T
Q1
Q3
mV
OS
R = 8I + 68FH, peak
L
Into shutdown
-59
-82
voltage, T = +25NC,
A
Click-and-Pop Level
K
A-weighted, 32
samples per second,
dBV
dB
CP
Out of shutdown
T
= +25NC (Notes 4, 5)
A
V
V
= 2.5V to 5.5V, T = +25NC
70
90
74
PVDD
A
f = 217Hz
Power-Supply Rejection Ratio
(Note 4)
PSRR
= 200mV
f = 1kHz
72
RIPPLE
P-P
f = 20kHz
49
V
V
V
V
V
V
V
V
V
V
V
V
= 5.0V
= 4.2V
= 3.7V
= 5.0V
= 4.2V
= 3.7V
= 5.0V
= 4.2V
= 3.7V
= 5.0V
= 4.2V
= 3.7V
3.2
2.2
PVDD
PVDD
PVDD
PVDD
PVDD
PVDD
PVDD
PVDD
PVDD
PVDD
PVDD
PVDD
THD+N = 10%
f = 1kHz
R = 4I + 33FH
L
1.7
2.6
1.8
1.4
1.8
1.2
0.96
1.4
1
THD+N = 1%
f = 1kHz
R = 4I + 33FH
L
Output Power
P
OUT
W
THD+N = 10%
f = 1kHz
R = 8I + 68FH
L
THD+N = 1%
f = 1kHz
R = 8I + 68FH
L
0.8
R = 4I,
L
0.03
0.03
0.1
P
= 1W
Total Harmonic Distortion Plus
Noise
OUT
THD+N
f
= 1kHz
%
IN
R = 8I
L
P
= 0.725W
OUT
A
A
A
A
A
= 12dB
31
26
V
V
V
V
V
= 9dB
= 6dB
= 3dB
= 0dB
Output Noise
V
A-weighted (Note 4)
23
FV
RMS
N
21
19
Efficiency
E
R = 8I, P
= 1.8W, f = 1kHz
93
%
kHz
kHz
A
L
OUT
Oscillator Frequency
Spread-Spectrum Bandwidth
Current Limit
f
300
20
OSC
2.8
155
Thermal Shutdown Level
NC
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4
MAX98314
Mono 3.2W Class D Amplifier
with Integrated Input Coupling Capacitors
ELECTRICAL CHARACTERISTICS (continued)
(V
= V
= V
= 5V, V
= 0V, A = 6dB (GAIN = PVDD), R = J, R connected between OUT+ to OUT-, AC measure-
PVDD
SHDN
GAIN
PGND V L L
ment bandwidth 20Hz to 22kHz, T = T
to T
, unless otherwise noted. Typical values are at T = +25NC.) (Note 2, 3)
A
MIN
MAX A
PARAMETER
Thermal Hysteresis
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
15
NC
DIGITAL INPUT (SHDN)
Input Voltage High
V
V
V
= 2.5V to 5.5V
1.4
V
V
INH
PVDD
PVDD
Input Voltage Low
V
= 2.5V to 5.5V
0.4
INL
Input Leakage Current
T
= +25NC
Q1
FA
A
Note 2: All devices are 100% production tested at T = +25NC. Specifications over temperature limits are guaranteed by design.
A
Note 3: Testing performed with a resistive load in series with an inductor to simulate an actual speaker load. For R = 4I,
L
L = 33FH. For R = 8I, L = 68FH.
Note 4: Amplifier inputs AC-coupled to ground.
L
Note 5: Mode transitions controlled by SHDN control pin.
Typical Operating Characteristics
(V
= V
= 5.0V, V
= 0V, A = 6dB, R = J, R connected between OUT+ to OUT-, AC measurement bandwidth 20Hz
PVDD
SHDN
PGND
V
L
L
to 22kHz, T = +25NC, unless otherwise noted.)
A
TOTAL HARMONIC DISTORTION PLUS
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY
NOISE vs. FREQUENCY
10
10
1
10
1
V
Z
= 5V
= 4I + 33µH
V
Z
= 4.2V
= 4I + 33µH
V
Z
= 3.7V
= 4I + 33µH
PVDD
LOAD
PVDD
LOAD
PVDD
LOAD
P
= 0.8W
OUT
P
= 1W
1
0.1
OUT
P
= 2W
OUT
0.1
0.1
P
= 1.5W
OUT
0.01
0.001
0.01
0.001
0.01
0.001
P
= 0.2W
OUT
P
= 0.5W
1k
OUT
10
100
1k
FREQUENCY (Hz)
10k
100k
10
100
10k
100k
10
100
1k
FREQUENCY (Hz)
10k
100k
FREQUENCY (Hz)
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY
10
1
10
1
10
1
V
Z
= 5V
= 8I + 68µH
V
Z
= 4.2V
= 8I + 68µH
V
Z
= 3.7V
= 8I + 68µH
PVDD
LOAD
PVDD
LOAD
PVDD
LOAD
P
= 1.2W
OUT
P
OUT
= 0.4W
P
= 0.6W
OUT
0.1
0.1
0.1
P
= 0.2W
OUT
0.01
0.001
0.01
0.001
0.01
0.001
P
= 0.2W
OUT
1k
P
= 0.3W
OUT
1k
10
100
10k
100k
10
100
10k
100k
10
100
1k
FREQUENCY (Hz)
10k
100k
FREQUENCY (Hz)
FREQUENCY (Hz)
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5
MAX98314
Mono 3.2W Class D Amplifier
with Integrated Input Coupling Capacitors
Typical Operating Characteristics (continued)
(V
= V
= 5.0V, V
= 0V, A = 6dB, R = J, R connected between OUT+ to OUT-, AC measurement bandwidth 20Hz
PVDD
SHDN
PGND
V
L
L
to 22kHz, T = +25NC, unless otherwise noted.)
A
TOTAL HARMONIC DISTORTION PLUS
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
NOISE vs. OUTPUT POWER
100
100
10
100
10
V
Z
= 5V
= 4I + 33µH
V
Z
= 4.2V
= 4I + 33µH
V
Z
= 3.7V
= 4I + 33µH
PVDD
LOAD
PVDD
LOAD
PVDD
LOAD
10
1
f = 6kHz
f = 6kHz
f = 1kHz
f = 6kHz
1
1
f = 1kHz
f = 1kHz
0.1
0.1
0.1
0.01
0.001
0.01
0.001
0.01
0.001
f = 100Hz
f = 100Hz
1.5
f = 100Hz
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0
OUTPUT POWER (W)
0
0.5
1.0
2.0
2.5
0
0.5
1.0
1.5
2.0
OUTPUT POWER (W)
OUTPUT POWER (W)
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
100
10
100
10
100
10
V
PVDD
LOAD
= 5V
V
PVDD
LOAD
= 4.3V
V
PVDD
LOAD
= 3.7V
Z
= 8I + 68µH
Z
= 8I + 68µH
Z
= 8I + 68µH
f = 6kHz
1
f = 6kHz
1
f = 6kHz
f = 1kHz
1
f = 1kHz
f = 1kHz
0.1
0.1
0.1
0.01
0.001
0.01
0.001
0.01
0.001
f = 100Hz
f = 100Hz
f = 100Hz
0
0.5
1.0
1.5
2.0
0
0.3
0.6
0.9
1.2
1.5
0
0.3
0.6
0.9
1.2
OUTPUT POWER (W)
OUTPUT POWER (W)
OUTPUT POWER (W)
OUTPUT POWER vs. LOAD RESISTANCE
OUTPUT POWER vs. LOAD RESISTANCE
OUTPUT POWER vs. SUPPLY VOLTAGE
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
2.5
2.0
1.5
1.0
0.5
0
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
V
= 5V
V
= 3.7V
PVDD
PVDD
f = 1kHz
Z
= 4I + 33µH
LOAD
THD+N = 10%
THD+N = 10%
THD+N = 10%
THD+N = 1%
THD+N = 1%
THD+N = 1%
10
1
100
1000
1
10
100
1000
2.5
3.0
3.5
4.0
4.5
5.0
5.5
R
(I)
R
(I)
LOAD
SUPPLY VOLTAGE (V)
LOAD
����������������������������������������������������������������� Maxim Integrated Products
6
MAX98314
Mono 3.2W Class D Amplifier
with Integrated Input Coupling Capacitors
Typical Operating Characteristics (continued)
(V
= V
= 5.0V, V
= 0V, A = 6dB, R = J, R connected between OUT+ to OUT-, AC measurement bandwidth 20Hz
PVDD
SHDN
PGND V L L
to 22kHz, T = +25NC, unless otherwise noted.)
A
GAIN vs. FREQUENCY
OUTPUT POWER vs. SUPPLY VOLTAGE
EFFICIENCY vs. OUTPUT POWER
20
2.5
100
90
80
70
60
50
40
30
20
10
0
GAIN = 12dB
V
= 5V
PVDD
f = 1kHz
GAIN = 9dB
15
10
5
Z
= 8I + 68µH
LOAD
2.0
1.5
1.0
0.5
0
Z
= 8I + 68µH
LOAD
Z
= 4I + 33µH
LOAD
THD+N = 10%
0
GAIN = 3dB
-5
GAIN = 0dB
GAIN = 6dB
-10
-15
-20
THD+N = 1%
10
100
1k
10k
100k
2.5
3.0
3.5
4.0
4.5
5.0
5.5
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5
OUTPUT POWER (W)
FREQUENCY (Hz)
SUPPLY VOLTAGE (V)
SUPPLY CURRENT
vs. SUPPLY VOLTAGE
POWER-SUPPLY REJECTION
RATIO vs. FREQUENCY
EFFICIENCY vs. OUTPUT POWER
2.0
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
100
90
80
70
60
50
40
30
20
10
0
100
90
80
70
60
50
40
30
20
10
0
V
= 200mV
= 8I + 68µH
V
= 3.7V
RIPPLE
P-P
PVDD
Z
LOAD
Z
= 8I + 68µH
LOAD
Z
= 4I + 33µH
LOAD
2.5
3.0
3.5
4.0
4.5
5.0
5.5
10
100
1k
FREQUENCY (Hz)
10k
100k
0
0.5
1.0
1.5
2.0
SUPPLY VOLTAGE (V)
OUTPUT POWER (W)
POWER-SUPPLY REJECTION
RATIO vs. SUPPLY VOLTAGE
COMMON-MODE REJECTION RATIO
vs. FREQUENCY
0
120
Z
LOAD
= 8I + 68µH
f = 1kHz
110
100
90
80
70
60
50
40
30
20
10
0
-10
-20
-30
-40
-50
-60
-70
-80
-90
-100
V
= 200mV
P-P
RIPPLE
A
= 9dB
V
A
= 6dB
V
A
= 12dB
V
A
= 3dB
V
A
= 0dB
V
2.5
3.0
3.5
4.0
4.5
5.0
5.5
10
100
1k
FREQUENCY (Hz)
10k
100k
SUPPLY VOLTAGE (V)
����������������������������������������������������������������� Maxim Integrated Products
7
MAX98314
Mono 3.2W Class D Amplifier
with Integrated Input Coupling Capacitors
Typical Operating Characteristics (continued)
(V
= V
= 5.0V, V
= 0V, A = 6dB, R = J, R connected between OUT+ to OUT-, AC measurement bandwidth 20Hz
PVDD
SHDN
PGND
V
L
L
to 22kHz, T = +25NC, unless otherwise noted.)
A
STARTUP RESPONSE
SHUTDOWN RESPONSE
MAX98314 toc24
MAX98314 toc25
V
SHDN
V
SHDN
2V/div
2V/div
I
SPKR_OUT
I
SPKR_OUT
100mA/div
100mA/div
1ms/div
NARROWBAND vs. FREQUENCY
WIDEBAND vs. FREQUENCY
0
-20
0
-20
RBW = 100Hz
f = 1kHz
= -60dBV
V
OUT
-40
-40
-60
-60
-80
-80
-100
-120
-140
-100
-120
10
100
1k
FREQUENCY (Hz)
10k
100k
0.1
1
10
100
FREQUENCY (MHz)
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8
MAX98314
Mono 3.2W Class D Amplifier
with Integrated Input Coupling Capacitors
Pin Configuration
TOP VIEW
(BUMP-SIDE DOWN)
MAX98314
1
2
3
+
A
B
C
OUT-
OUT+
PVDD
PGND
SHDN
N.C.
GAIN
IN+
IN-
WLP
(0.3mm pitch)
Pin Description
BUMP
A1
NAME
OUT-
OUT+
PVDD
PGND
N.C.
FUNCTION
Negative Speaker Output
Positive Speaker Output
A2
A3
Power Supply. Bypass PVDD with a 0.1FF and 10FF capacitor to PGND.
Power Ground
B1
B2
No Connection. Can be left unconnected or connected to PGND.
Gain Select. See Table 1 for GAIN settings.
B3
GAIN
C1
SHDN
IN-
Active-Low Shutdown Input. Drive SHDN low to place the device in shutdown.
Inverting Audio Input
C2
C3
IN+
Noninverting Audio Input
����������������������������������������������������������������� Maxim Integrated Products
9
MAX98314
Mono 3.2W Class D Amplifier
with Integrated Input Coupling Capacitors
Amplifier Current Limit
If the output current of the speaker amplifier exceeds the
Detailed Description
The MAX98314 features low quiescent current, a low-
power shutdown mode, comprehensive click-and-pop
suppression, and excellent RF immunity.
current limit (2.8A typ), the IC disables the outputs for
approximately 100Fs. At the end of 100Fs, the outputs
are reenabled. If the fault condition still exists, the IC
continues to disable and reenable the outputs until the
fault condition is removed.
The IC offers Class AB audio performance with Class D
efficiency in a minimal board-space solution. The Class
D amplifier features spread-spectrum modulation, edge-
rate, and overshoot control circuitry that offers significant
improvements to switch-mode amplifier radiated emis-
sions.
Selectable Amplifier Gain
The IC offers five programmable gain settings, selectable
by a single gain input (GAIN).
The amplifier features click-and-pop suppression that
reduces audible transients on startup and shutdown.
The amplifier additionally includes thermal overload and
short-circuit protection.
Table 1. GAIN Selection
GAIN PIN
MAXIMUM GAIN (dB)
Connect to PGND
12
Connect to PGND through
100kI Q5%
Highly linear, integrated input coupling capacitors (C )
IN
9
6
3
0
reduce solution size and provide excellent THD+N,
PSRR, and CMRR performance at low frequencies vs.
standard Class D amplifiers using external input capaci-
tors.
Connect to PVDD
Connect to PVDD through
100kI Q5%
Unconnected
Class D Speaker Amplifier
The IC’s filterless Class D amplifier offers much higher
efficiency than Class AB amplifiers. The high efficiency
of a Class D amplifier is due to the switching operation of
the output stage transistors. Any power loss associated
with the Class D output stage is mostly due to the I2R loss
of the MOSFET on-resistance and quiescent switching
current overhead.
Integrated Input Coupling Capacitors (C
)
IN
The IC integrates two 0.011FF input coupling capacitors,
C . The input coupling capacitors, in conjunction with
IN
the amplifier’s internal input resistance (R ), form a first-
IN
order highpass filter that removes the DC bias from the
incoming signal. These capacitors allow the amplifier to
bias the signal to an optimum DC level.
Ultra-Low EMI Filterless Output Stage
Traditional Class D amplifiers require the use of external
LC filters, or shielding, to meet electromagnetic inter-
ference (EMI) regulation standards. Maxim’s patented
active emissions limiting edge-rate control circuitry and
spread-spectrum modulation reduces EMI emissions,
while maintaining up to 93% efficiency.
90
70
50
The spread-spectrum modulation mode flattens wide-
band spectral components, while proprietary techniques
ensure that the cycle-to-cycle variation of the switching
period does not degrade audio reproduction or effi-
ciency. The IC’s spread-spectrum modulator randomly
varies the switching frequency by Q20kHz around the
center frequency (300kHz). Above 10MHz, the wideband
spectrum looks like noise for EMI purposes (Figure 1).
EN5502B LIMIT
30
HORIZONTAL
10
VERTICAL
-10
0
100 200 300 400 500 600 700 800 900 1000
FREQUENCY (MHz)
Figure 1. EMI Performance with 60cm of Speaker Cable, No
Output Filter
���������������������������������������������������������������� Maxim Integrated Products 10
MAX98314
Mono 3.2W Class D Amplifier
with Integrated Input Coupling Capacitors
Assuming zero source impedance, the -3dB corner
frequency, f , is:
Applications Information
-3dB
f
= 1/2GR C [Hz]
Filterless Class D Operation
Traditional Class D amplifiers require an output filter.
The filter adds cost and size, and decreases efficiency
and THD+N performance. The IC’s filterless modulation
scheme does not require an output filter.
-3dB
IN IN
The 100ppm/V voltage coefficient of the integrated input
coupling capacitor results in excellent low-frequency
THD+N performance. Figure 2 illustrates the superior
linearity of the IC’s integrated input coupling capacitors
compared to a similar amplifier with external 0.01FF X7R
and X5R 0402 input coupling capacitors.
Because the switching frequency of the IC is well beyond
the bandwidth of most speakers, voice coil movement
due to the switching frequency is very small. Use a
speaker with a series inductance > 10FH. Typical 8I
speakers exhibit series inductances in the 20FH to
100FH range.
TOTAL HARMONIC DISTORTION
PLUS NOISE vs. FREQUENCY
10
V
PVDD
LOAD
= 4.2V
= 8I + 68µH
Z
Speaker Amplifier Power-Supply Input (PVDD)
PVDD powers the speaker amplifier and ranges from
2.5V to 5.5V. Bypass PVDD with a 0.1FF and 10FF
capacitor to PGND. Apply additional bulk capacitance
at the device if long input traces between PVDD and the
power source are used.
P
= 600mW
OUT
1.0
0.1
X7R CAPS
X5R CAPS
0.01
0.001
Layout and Grounding
Proper layout and grounding are essential for optimum
performance. Good grounding improves audio perfor-
mance and prevents switching noise from coupling into
the audio signal.
MAX98314 INTERNAL CAPS
10
100
1k
10k
100k
FREQUENCY (Hz)
Use wide, low-resistance output traces. As the load
impedance decreases, the current drawn from the
device increases. At higher current, the resistance of the
output traces decrease the power delivered to the load.
For example, if 2W is delivered from the device output to
a 4Iload through 100mIof total speaker trace, 1.904W
is delivered to the speaker. If power is delivered through
10mI of total speaker trace, 1.99W is delivered to the
speaker. Wide output, supply, and ground traces also
improve the power dissipation of the device.
Figure 2. Low-Frequency THD+N Performance
Shutdown
The IC features a low-power shutdown mode, drawing
< 0.1FA (typ) of supply current. Drive SHDN low to put
the IC into shutdown.
Click-and-Pop Suppression
The speaker amplifier features Maxim’s comprehensive
click-and-pop suppression. During startup, the click-
and-pop suppression circuitry reduces any audible
transient sources internal to the device. When entering
shutdown, the differential speaker outputs ramp down to
PGND quickly and simultaneously.
The IC is inherently designed for excellent RF immunity.
For best performance, add ground fills around all signal
traces on top or bottom PCB layers.
���������������������������������������������������������������� Maxim Integrated Products 11
MAX98314
Mono 3.2W Class D Amplifier
with Integrated Input Coupling Capacitors
WLP Applications Information
For the latest application details on WLP construction,
0.18mm
dimensions, tape carrier information, PCB techniques,
bump-pad layout, and recommended reflow temperature
profile, as well as the latest information on reliability test-
ing results, refer to Application Note 1891: Wafer-Level
Packaging (WLP) and Its Applications. Figure 3 shows
the dimensions of the WLP balls used on the IC.
Ordering Information
0.18mm
PART
TEMP RANGE
PIN-PACKAGE
MAX98314EWL+
-40NC to +85NC
9 WLP
Figure 3. WLP Ball Dimensions
+Denotes a lead(Pb)-free/RoHS-compliant package.
���������������������������������������������������������������� Maxim Integrated Products 12
MAX98314
Mono 3.2W Class D Amplifier
with Integrated Input Coupling Capacitors
Package Information
For the latest package outline information and land patterns (footprints), go to www.maxim-ic.com/packages. Note that a “+”, “#”, or
“-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains
to the package regardless of RoHS status.
PACKAGE TYPE
PACKAGE CODE
OUTLINE NO.
21-0539
LAND PATTERN NO.
Refer to
Application Note 1891
9 WLP (0.3mm pitch)
W90A0+1
COMMON DIMENSIONS
MARKING
0.75
0.16
0.59
0.040
0.21
0.60
0.60
0.30
A
A1
A2
A3
b
0.05
0.03
E
PIN 1
INDICATOR
A3
1
REF
A
BASIC
0.03
A1
D
A2
AAAA
A
BASIC
BASIC
BASIC
D1
E1
e
0.05
S
See
S
Note 7
SD
0.00 BASIC
0.00 BASIC
TOP VIEW
SIDE VIEW
SE
E
D
DEPOPULATED
BUMPS
MAX
0.98
MIN
MIN
MAX
0.98
PKG. CODE
W90A0+1
NONE
0.95
0.95
E1
SE
e
NOTES:
SD
1. Terminal pitch is defined by terminal center to center value.
2. Outer dimension is defined by center lines between scribe lines.
3. All dimensions in millimeter.
B
C
4. Marking shown is for package orientation reference only.
5. Tolerance is 0.02 unless specified otherwise.
B
D1
6. All dimensions apply to PbFree (+) package codes only.
7. Front - side finish can be either Black or Clear.
A
b
1
2
3
A
BOTTOM VIEW
TITLE
Package Outline
9 bumps, WLP Pkg. 0.3MM Pitch
REV.
APPROVAL
DOCUMENT CONTROL NO.
-DRAWING NOT TO SCALE-
1
1
21-0539
B
���������������������������������������������������������������� Maxim Integrated Products 13
MAX98314
Mono 3.2W Class D Amplifier
with Integrated Input Coupling Capacitors
Revision History
REVISION REVISION
PAGES
CHANGED
DESCRIPTION
NUMBER
DATE
0
11/11
Initial release
—
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied.
Maxim reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits) shown in the Electrical
Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
14
©
2011 Maxim Integrated Products
Maxim is a registered trademark of Maxim Integrated Products, Inc.
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