MAXIM MAX98314_1111

19-6124; Rev 0; 11/11
EVALUATION KIT AVAILABLE
MAX98314
Mono 3.2W Class D Amplifier
with Integrated Input Coupling Capacitors
General Description
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).
Active emissions limiting (AEL) edge rate and overshoot
control circuitry and a filterless spread-spectrum modulation (SSM) scheme greatly reduce EMI and eliminate
the need for output filtering found in traditional Class D
devices.
The IC’s low 0.95mA at 3.7V, 1.2mA at 5.0V quiescent
current extends battery life in portable applications.
Highly linear, integrated input coupling capacitors (CIN)
reduce solution size and provide excellent THD+N, PSRR,
and CMRR performance at low frequencies vs. standard
Class D amplifiers using external input capacitors.
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.
Features
SIntegrated Input Coupling Capacitors with
Excellent Linearity
fC = 100Hz (6dB)
fC = 200Hz (12dB)
SLow Quiescent Current
0.95mA at 3.7V
1.2mA at 5.0V
SDelivers High Output Power at 10% THD+N
3.2W into 4I, VPVDD = 5V
960mW into 8I, VPVDD = 3.7V
SUltra-Low Noise: 19µV
SEliminates Output Filtering Requirement
Spread Spectrum and Active Emissions Limiting
SClick-and-Pop Suppression
SThermal and Overcurrent Protection
SLow Current Shutdown Mode
SSmall, Space-Saving Package
Applications
Simplified Block Diagram
Mobile Phones
Portable Audio
Notebook Computers
CIN
MAX98314
MP3 Players
Netbook Computers
VoIP Phones
Ordering Information appears at end of data sheet.
CLASS D
MODULATOR
AND H-BRIDGE
CIN
GAIN CONTROL
For related parts and recommended products to use with this part, refer to: www.maxim-ic.com/MAX98314.related
����������������������������������������������������������������� Maxim Integrated Products 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
GAIN
IN+
IN-
B3
LOW-EMI
DRIVER
A1
OUT-
A2
OUT+
C3
C2
PGND
CLASS D
MODULATOR
PVDD
LOW-EMI
DRIVER
PGND
B1
PGND
*SYSTEM BULK CAPACITANCE.
����������������������������������������������������������������� Maxim Integrated Products 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 (VPVDD + 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 (TA = +70NC) for Multilayer Board
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
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 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 (BJA).........102NC/W
Junction-to-Case Thermal Resistance (BJC)................47NC/W
Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a fourlayer board. For detailed information on package thermal considerations, refer to www.maxim-ic.com/thermal-tutorial.
ELECTRICAL CHARACTERISTICS
(VPVDD = VSHDN = VGAIN = 5V, VPGND = 0V, AV = 6dB (GAIN = PVDD), RL = J, RL connected between OUT+ to OUT-, AC measurement bandwidth 20Hz to 22kHz, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25NC.) (Note 2, 3)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
AMPLIFIER CHARACTERISTICS
Supply Voltage Range
VPVDD
Guaranteed by PSRR test
Undervoltage Lockout
UVLO
PVDD falling
Quiescent Current
IPVDD
Shutdown Supply Current
ISHDN
Turn-On Time
tON
Bias Voltage
VBIAS
Voltage Gain
AV
Input Capacitance
CIN
2.5
5.5
V
1.8
2.2
V
VPVDD = 5V
1.2
1.8
VPVDD = 3.7V
0.95
VSHDN = 0V, TA = +25NC
< 0.1
10
FA
3.7
10
ms
f = 1kHz
VPVDD/2
11.75
12
12.25
GAIN connected to PGND
through 100kI Q5% resistor
8.75
9
9.25
GAIN connected to PVDD
5.75
6
6.25
GAIN connected to PVDD
through 100kI Q5% resistor
2.75
3
3.25
GAIN unconnected
-0.25
0
+0.25
0.011
AV = 12dB
fC
-3dB down
AV = 6dB
dB
FF
199
AV = 9dB
Highpass Corner Frequency
V
GAIN connected to PGND
All gains
mA
139
63
100
AV = 3dB
70
AV = 0dB
50
189
Hz
����������������������������������������������������������������� Maxim Integrated Products 3
MAX98314
Mono 3.2W Class D Amplifier
with Integrated Input Coupling Capacitors
ELECTRICAL CHARACTERISTICS (continued)
(VPVDD = VSHDN = VGAIN = 5V, VPGND = 0V, AV = 6dB (GAIN = PVDD), RL = J, RL connected between OUT+ to OUT-, AC measurement bandwidth 20Hz to 22kHz, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25NC.) (Note 2, 3)
PARAMETER
SYMBOL
Common-Mode Rejection Ratio
CMRR
Output Offset Voltage
Click-and-Pop Level
Power-Supply Rejection Ratio
(Note 4)
Output Power
Output Noise
TA = +25NC (Note 4)
Q1
KCP
RL = 8I + 68FH, peak
voltage, TA = +25NC,
A-weighted, 32
samples per second,
TA = +25NC (Notes 4, 5)
PSRR
THD+N
E
Oscillator Frequency
TYP
VOS
VN
Efficiency
MIN
67
POUT
Total Harmonic Distortion Plus
Noise
CONDITIONS
fIN = 1kHz, input referred
fOSC
Into shutdown
Out of shutdown
Q3
mV
f = 1kHz
-82
70
90
74
49
THD+N = 10%
f = 1kHz
RL = 4I + 33FH
3.2
VPVDD = 4.2V
2.2
VPVDD = 3.7V
1.7
THD+N = 1%
f = 1kHz
RL = 4I + 33FH
VPVDD = 5.0V
2.6
VPVDD = 4.2V
1.8
VPVDD = 3.7V
1.4
THD+N = 10%
f = 1kHz
RL = 8I + 68FH
VPVDD = 5.0V
1.8
VPVDD = 4.2V
1.2
VPVDD = 3.7V
0.96
THD+N = 1%
f = 1kHz
RL = 8I + 68FH
VPVDD = 5.0V
1.4
VPVDD = 4.2V
1
VPVDD = 3.7V
0.8
RL = 4I,
POUT = 1W
0.03
RL = 8I
POUT = 0.725W
0.03
W
0.1
%
AV = 12dB
31
AV = 9dB
26
AV = 6dB
23
AV = 3dB
21
AV = 0dB
19
RL = 8I, POUT = 1.8W, f = 1kHz
dB
72
VPVDD = 5.0V
A-weighted (Note 4)
dB
-59
f = 20kHz
fIN = 1kHz
UNITS
dBV
VPVDD = 2.5V to 5.5V, TA = +25NC
f = 217Hz
VRIPPLE = 200mVP-P
MAX
FVRMS
93
%
300
kHz
Spread-Spectrum Bandwidth
20
kHz
Current Limit
2.8
A
Thermal Shutdown Level
155
NC
����������������������������������������������������������������� Maxim Integrated Products 4
MAX98314
Mono 3.2W Class D Amplifier
with Integrated Input Coupling Capacitors
ELECTRICAL CHARACTERISTICS (continued)
(VPVDD = VSHDN = VGAIN = 5V, VPGND = 0V, AV = 6dB (GAIN = PVDD), RL = J, RL connected between OUT+ to OUT-, AC measurement bandwidth 20Hz to 22kHz, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25NC.) (Note 2, 3)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
Thermal Hysteresis
MAX
UNITS
15
NC
DIGITAL INPUT (SHDN)
Input Voltage High
VINH
VPVDD = 2.5V to 5.5V
Input Voltage Low
VINL
VPVDD = 2.5V to 5.5V
0.4
V
TA = +25NC
Q1
FA
Input Leakage Current
1.4
V
Note 2: All devices are 100% production tested at TA = +25NC. Specifications over temperature limits are guaranteed by design.
Note 3: Testing performed with a resistive load in series with an inductor to simulate an actual speaker load. For RL = 4I,
L = 33FH. For RL = 8I, L = 68FH.
Note 4: Amplifier inputs AC-coupled to ground.
Note 5: Mode transitions controlled by SHDN control pin.
Typical Operating Characteristics
(VPVDD = VSHDN = 5.0V, VPGND = 0V, AV = 6dB, RL = J, RL connected between OUT+ to OUT-, AC measurement bandwidth 20Hz
to 22kHz, TA = +25NC, unless otherwise noted.)
POUT = 2W
POUT = 1.5W
0.01
10
POUT = 1W
0.1
VPVDD = 3.7V
ZLOAD = 4I + 33µH
POUT = 0.8W
1
0.01
0.1
0.01
POUT = 0.2W
POUT = 0.5W
0.001
0.001
10k
100k
0.001
10
100
1k
10k
100k
100
1k
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
THD+N (%)
1
0.1
0.01
0.1
0.01
0.1
POUT = 0.2W
0.01
0.001
FREQUENCY (Hz)
POUT = 0.4W
POUT = 0.3W
0.001
1k
VPVDD = 3.7V
ZLOAD = 8I + 68µH
1
POUT = 0.6W
POUT = 0.2W
100
10
THD+N (%)
POUT = 1.2W
VPVDD = 4.2V
ZLOAD = 8I + 68µH
MAX98314 toc06
FREQUENCY (Hz)
VPVDD = 5V
ZLOAD = 8I + 68µH
10
10
FREQUENCY (Hz)
1
THD+N (%)
1k
MAX98314 toc05
10
100
MAX98314 toc04
10
MAX98314 toc03
VPVDD = 4.2V
ZLOAD = 4I + 33µH
1
THD+N (%)
THD+N (%)
1
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY
THD+N (%)
VPVDD = 5V
ZLOAD = 4I + 33µH
0.1
10
MAX98314 toc01
10
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY
MAX98314 toc02
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY
10k
100k
0.001
10
100
1k
FREQUENCY (Hz)
10k
100k
10
100
1k
10k
100k
FREQUENCY (Hz)
����������������������������������������������������������������� Maxim Integrated Products 5
MAX98314
Mono 3.2W Class D Amplifier
with Integrated Input Coupling Capacitors
Typical Operating Characteristics (continued)
(VPVDD = VSHDN = 5.0V, VPGND = 0V, AV = 6dB, RL = J, RL connected between OUT+ to OUT-, AC measurement bandwidth 20Hz
to 22kHz, TA = +25NC, unless otherwise noted.)
f = 1kHz
0.01
f = 1kHz
0.1
0.01
f = 100Hz
0.001
1.0
1.5
2.0
2.5
3.0
3.5
4.0
0.5
1.0
1.5
2.0
2.5
0
f = 6kHz
0.1
f = 1kHz
MAX98314 toc09
f = 6kHz
1
f = 1kHz
0.1
0.01
0.01
f = 100Hz
f = 100Hz
f = 100Hz
0.001
0.001
0.001
1.5
0
2.0
0.3
OUTPUT POWER vs. LOAD RESISTANCE
VPVDD = 5V
4.0
1.2
0
1.5
0.3
3.0
THD+N = 10%
2.0
1.5
1.0
VPVDD = 3.7V
2.0
THD+N = 10%
THD+N = 1%
0.5
0.9
1.2
OUTPUT POWER vs. SUPPLY VOLTAGE
1.5
1.0
0.6
OUTPUT POWER (W)
OUTPUT POWER vs. LOAD RESISTANCE
OUTPUT POWER (W)
3.5
0.9
2.5
MAX98314 toc13
4.5
0.6
OUTPUT POWER (W)
4.5
f = 1kHz
ZLOAD = 4I + 33µH
4.0
3.5
OUTPUT POWER (W)
1.0
OUTPUT POWER (W)
MAX98314 toc14
0.5
VPVDD = 3.7V
ZLOAD = 8I + 68µH
10
THD+N (%)
THD+N (%)
10
MAX98314 toc12
VPVDD = 4.3V
ZLOAD = 8I + 68µH
1
100
MAX98314 toc11
100
0.01
3.0
THD+N = 10%
2.5
2.0
1.5
THD+N = 1%
1.0
0.5
THD+N = 1%
0
0
1
2.0
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
f = 1kHz
0.5
1.5
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
f = 6kHz
2.5
1.0
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
1
0
0.5
OUTPUT POWER (W)
10
THD+N (%)
0
OUTPUT POWER (W)
VPVDD = 5V
ZLOAD = 8I + 68µH
0.1
0.001
OUTPUT POWER (W)
MAX98314 toc10
100
OUTPUT POWER (W)
f = 100Hz
0.001
0.5
f = 1kHz
0.1
0.01
f = 100Hz
0
f = 6kHz
1
MAX98314 toc15
0.1
f = 6kHz
1
VPVDD = 3.7V
ZLOAD = 4I + 33µH
10
THD+N (%)
f = 6kHz
VPVDD = 4.2V
ZLOAD = 4I + 33µH
10
THD+N (%)
THD+N (%)
10
100
MAX98314 toc08
VPVDD = 5V
ZLOAD = 4I + 33µH
1
100
MAX98314 toc07
100
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
10
100
RLOAD (I)
1000
1
10
100
RLOAD (I)
1000
0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
SUPPLY VOLTAGE (V)
����������������������������������������������������������������� Maxim Integrated Products 6
MAX98314
Mono 3.2W Class D Amplifier
with Integrated Input Coupling Capacitors
Typical Operating Characteristics (continued)
(VPVDD = VSHDN = 5.0V, VPGND = 0V, AV = 6dB, RL = J, RL connected between OUT+ to OUT-, AC measurement bandwidth 20Hz
to 22kHz, TA = +25NC, unless otherwise noted.)
GAIN vs. FREQUENCY
1.5
1.0
0
GAIN = 3dB
GAIN = 0dB
80
GAIN = 6dB
-10
THD+N = 1%
0.5
3.0
3.5
4.0
4.5
5.0
40
10
10
5.5
100
10k
1k
0
100k
1.0
1.5
2.0
2.5
3.0
EFFICIENCY vs. OUTPUT POWER
SUPPLY CURRENT
vs. SUPPLY VOLTAGE
POWER-SUPPLY REJECTION
RATIO vs. FREQUENCY
1.8
1.6
60
50
40
80
1.4
70
1.2
60
1.0
0.8
50
40
0.6
30
20
0.4
20
10
0.2
10
0
0
30
1.0
1.5
0
3.0
2.5
2.0
3.5
4.0
4.5
120
110
100
MAX98314 toc22
f = 1kHz
VRIPPLE = 200mVP-P
-20
1k
10k
100k
FREQUENCY (Hz)
CMRR (dB)
-40
-50
-60
-70
ZLOAD = 8I + 68µH
AV = 9dB
90
-30
PSRR (dB)
100
COMMON-MODE REJECTION RATIO
vs. FREQUENCY
POWER-SUPPLY REJECTION
RATIO vs. SUPPLY VOLTAGE
0
10
5.5
SUPPLY VOLTAGE (V)
OUTPUT POWER (W)
-10
5.0
MAX98314 toc23
0.5
VRIPPLE = 200mVP-P
ZLOAD = 8I + 68µH
90
PSRR (dB)
SUPPLY CURRENT (mA)
ZLOAD = 4I + 33µH
100
MAX98314 toc20
MAX98314 toc19
ZLOAD = 8I + 68µH
2.0
3.5
MAX98314 toc21
OUTPUT POWER (W)
VPVDD = 3.7V
0
0.5
0
FREQUENCY (Hz)
90
70
50
SUPPLY VOLTAGE (V)
100
80
ZLOAD = 4I + 33µH
60
20
-20
2.5
ZLOAD = 8I + 68µH
70
30
-15
0
EFFICIENCY (%)
5
VPVDD = 5V
90
MAX98314 toc18
10
-5
100
EFFICIENCY (%)
THD+N = 10%
EFFICIENCY vs. OUTPUT POWER
GAIN = 12dB
GAIN = 9dB
15
GAIN (dB)
OUTPUT POWER (W)
MAX98304 toc16
f = 1kHz
ZLOAD = 8I + 68µH
2.0
20
MAX98314 toc17
OUTPUT POWER vs. SUPPLY VOLTAGE
2.5
AV = 6dB
AV = 12dB
80
70
60
50
40
AV = 3dB
AV = 0dB
30
20
10
0
-80
-90
-100
2.5
3.0
3.5
4.0
4.5
SUPPLY VOLTAGE (V)
5.0
5.5
10
100
1k
10k
100k
FREQUENCY (Hz)
����������������������������������������������������������������� Maxim Integrated Products 7
MAX98314
Mono 3.2W Class D Amplifier
with Integrated Input Coupling Capacitors
Typical Operating Characteristics (continued)
(VPVDD = VSHDN = 5.0V, VPGND = 0V, AV = 6dB, RL = J, RL connected between OUT+ to OUT-, AC measurement bandwidth 20Hz
to 22kHz, TA = +25NC, unless otherwise noted.)
STARTUP RESPONSE
SHUTDOWN RESPONSE
MAX98314 toc24
MAX98314 toc25
VSHDN
2V/div
VSHDN
2V/div
ISPKR_OUT
100mA/div
ISPKR_OUT
100mA/div
1ms/div
-40
-60
-80
-100
f = 1kHz
VOUT = -60dBV
-20
OUTPUT MAGNITUDE (dBV)
OUTPUT MAGNITUDE (dBV)
MAX98314 toc26
RBW = 100Hz
-20
0
MAX98314 toc27
NARROWBAND vs. FREQUENCY
WIDEBAND vs. FREQUENCY
0
-40
-60
-80
-100
-120
-140
-120
0.1
1
10
FREQUENCY (MHz)
100
10
100
1k
10k
100k
FREQUENCY (Hz)
����������������������������������������������������������������� Maxim Integrated Products 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
OUT-
OUT+
PVDD
B
PGND
N.C.
GAIN
C
SHDN
IN-
IN+
+
WLP
(0.3mm pitch)
Pin Description
BUMP
NAME
A1
OUT-
Negative Speaker Output
FUNCTION
A2
OUT+
Positive Speaker Output
A3
PVDD
Power Supply. Bypass PVDD with a 0.1FF and 10FF capacitor to PGND.
B1
PGND
Power Ground
B2
N.C.
No Connection. Can be left unconnected or connected to PGND.
B3
GAIN
Gain Select. See Table 1 for GAIN settings.
C1
C2
SHDN
IN-
Active-Low Shutdown Input. Drive SHDN low to place the device in shutdown.
Inverting Audio Input
C3
IN+
Noninverting Audio Input
����������������������������������������������������������������� Maxim Integrated Products 9
MAX98314
Mono 3.2W Class D Amplifier
with Integrated Input Coupling Capacitors
The MAX98314 features low quiescent current, a lowpower shutdown mode, comprehensive click-and-pop
suppression, and excellent RF immunity.
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, edgerate, and overshoot control circuitry that offers significant
improvements to switch-mode amplifier radiated emissions.
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.
Highly linear, integrated input coupling capacitors (CIN)
reduce solution size and provide excellent THD+N,
PSRR, and CMRR performance at low frequencies vs.
standard Class D amplifiers using external input capacitors.
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.
Ultra-Low EMI Filterless Output Stage
Traditional Class D amplifiers require the use of external
LC filters, or shielding, to meet electromagnetic interference (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.
The spread-spectrum modulation mode flattens wideband spectral components, while proprietary techniques
ensure that the cycle-to-cycle variation of the switching
period does not degrade audio reproduction or efficiency. 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).
Amplifier Current Limit
If the output current of the speaker amplifier exceeds the
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.
Selectable Amplifier Gain
The IC offers five programmable gain settings, selectable
by a single gain input (GAIN).
Table 1. GAIN Selection
GAIN PIN
MAXIMUM GAIN (dB)
Connect to PGND
12
Connect to PGND through
100kI Q5%
9
Connect to PVDD
6
Connect to PVDD through
100kI Q5%
3
Unconnected
0
Integrated Input Coupling Capacitors (CIN)
The IC integrates two 0.011FF input coupling capacitors,
CIN. The input coupling capacitors, in conjunction with
the amplifier’s internal input resistance (RIN), form a firstorder 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.
90
EMISSIONS LEVEL (dBµV/m)
Detailed Description
70
50
EN5502B LIMIT
30
HORIZONTAL
10
-10
VERTICAL
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-3dB, is:
Filterless Class D Operation
f-3dB = 1/2GRINCIN [Hz]
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.
TOTAL HARMONIC DISTORTION
PLUS NOISE vs. FREQUENCY
10
THD+N (%)
1.0
VPVDD = 4.2V
ZLOAD = 8I + 68µH
POUT = 600mW
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.
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.
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.
X7R CAPS
X5R CAPS
0.1
Applications Information
Layout and Grounding
0.01
MAX98314 INTERNAL CAPS
0.001
10
100
1k
10k
100k
FREQUENCY (Hz)
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 clickand-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.
Proper layout and grounding are essential for optimum
performance. Good grounding improves audio performance and prevents switching noise from coupling into
the audio signal.
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 4I load through 100mI of 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.
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,
dimensions, tape carrier information, PCB techniques,
bump-pad layout, and recommended reflow temperature
profile, as well as the latest information on reliability testing 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.
0.18mm
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.
LAND PATTERN NO.
9 WLP (0.3mm pitch)
W90A0+1
21-0539
Refer to
Application Note 1891
COMMON DIMENSIONS
PIN 1
INDICATOR
MARKING
E
A3
1
A
0.75
0.05
A1
0.16
0.03
0.59 REF
A2
A
A1
D
AAAA
A2
TOP VIEW
See
Note 7
SIDE VIEW
E
E1
0.21
b
A
0.05 S
S
0.040 BASIC
A3
E1
0.60 BASIC
e
0.30 BASIC
SD
0.00
BASIC
SE
0.00
BASIC
D
PKG. CODE
MIN
MAX
W90A0+1
0.95
0.98
0.03
D1
0.60 BASIC
MIN
MAX
0.95
0.98
DEPOPULATED
BUMPS
NONE
SE
e
B
SD
C
B
D1
A
1
2
3
b
NOTES:
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.
4. Marking shown is for package orientation reference only.
5. Tolerance is ± 0.02 unless specified otherwise.
6. All dimensions apply to PbFree (+) package codes only.
7. Front - side finish can be either Black or Clear.
A
BOTTOM VIEW
TITLE
-DRAWING NOT TO SCALE-
APPROVAL
Package Outline
9 bumps, WLP Pkg. 0.3MM Pitch
DOCUMENT CONTROL NO.
21-0539
REV.
B
1
1
���������������������������������������������������������������� Maxim Integrated Products 13
MAX98314
Mono 3.2W Class D Amplifier
with Integrated Input Coupling Capacitors
Revision History
REVISION
NUMBER
REVISION
DATE
0
11/11
DESCRIPTION
Initial release
PAGES
CHANGED
—
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
© 2011
Maxim Integrated Products 14
Maxim is a registered trademark of Maxim Integrated Products, Inc.