MAX9701ETG+T Fast Delivery |IC PHOENIX CO.,LIMITED

MAX9701ETG+T ,1.3W, Filterless, Stereo Class D Audio Power AmplifierBlock DiagramNotebooksVDDHandheld Gaming ConsolesMAX9701Docking StationsINR+RIGHTMP3 PlayersMODULAT ..
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MAX9703ETJ ,15W, Filterless, Spread-Spectrum Mono/Stereo Class D AmplifiersFeaturesThe MAX9703/MAX9704 mono/stereo class D audio ♦ Filterless Class D Amplifierpower amplifier ..
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MAX9704ETJ+ ,10W Stereo/15W Mono, Filterless, Spread-Spectrum, Class D AmplifiersElectrical Characteristics(V = 15V, AGND = PGND = 0V, SHDN ≥ V , A = 16dB, C = C = 0.47μF, C = 0.01 ..
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MAX9701ETG+T
1.3W, Filterless, Stereo Class D Audio Power Amplifier
General Description
The MAX9701 stereo Class D audio power amplifier pro-
vides Class AB amplifier audio performance with the
benefits of Class D efficiency, eliminating the need for a
heatsink while extending battery life. The MAX9701
delivers up to 1.3W per channel into an 8Ωload while
offering 87% efficiency. Maxim’s next-generation, low-
EMI modulation scheme allows the amplifier to operate
without an external LC filter while still meeting FCC EMI
emission levels.
The MAX9701 offers two modulation schemes: a fixed-fre-
quency (FFM) mode, and a spread-spectrum (SSM)
mode that reduces EMI-radiated emissions. The
MAX9701 oscillator can be synchronized to an external
clock through the SYNC input, allowing synchronization of
multiple Maxim Class D amplifiers. The sync output
(SYNC_OUT) can be used for a master-slave application
where more channels are required. The MAX9701 fea-
tures a fully differential architecture, a full bridge-tied load
(BTL) output, and comprehensive click-and-pop suppres-
sion. The device features internally set gains of 0dB, 6dB,
12dB, and 18dB selected through two gain-select inputs,
further reducing external component count.
The MAX9701 features high 80dB PSRR, less than 0.1%
THD+N, and SNR in excess of 88dB. Short-circuit and
thermal-overload protection prevent the device from
being damaged during a fault condition. The MAX9701 is
available in 24-pin thin QFN-EP (4mm x 4mm x 0.8mm)
and 20-bump UCSP™ (2mm x 2.5mm x 0.6mm) pack-
ages. The MAX9701 is specified over the extended
-40°C to +85°C temperature range.
Applications
Cellular Phones
Notebooks
Handheld Gaming Consoles
Docking Stations
MP3 Players
FeaturesSpread-Spectrum Modulation Lowers Radiated
EmissionsSingle-Supply Operation (2.5V to 5.5V)1.3W Stereo Output (8Ω, VDD= 5V, THD+N = 1%)No LC Output Filter Required87% Efficiency (RL= 8Ω, POUT= 1000mW)Less Than 0.1% THD+NHigh 80dB PSRRFully Differential InputsIntegrated Click-and-Pop SuppressionTypical Low Quiescent Current (9mA)Typical Low-Power Shutdown Mode (0.1µA)Short-Circuit and Thermal-Overload ProtectionAvailable in Thermally Efficient, Space-Saving
Packages
24-Pin Thin QFN-EP (4mm x 4mm x 0.8mm)
20-Bump UCSP (2mm x 2.5mm x 0.6mm)
MAX9701
1.3W, Filterless, Stereo Class D Audio
Power Amplifier
MAX9701
GAIN2
GAIN1
VDD
GAIN
RIGHT
MODULATOR
AND H-BRIDGE
SYNCOSCILLATOR
LEFT
MODULATOR
AND H-BRIDGE
INR+
INR-
INL+
INL-
SYNC_OUT
Block Diagram
Ordering Information
19-3457; Rev 3; 3/09
PART TEMP RANGE PIN-PACKAGE
MAX9701EBP+TG45 -40°C to +85°C 20 UCSP
MAX9701ETG+ -40°C to +85°C 24 TQFN-EP*
Pin Configurations appear at end of data sheet.
UCSP is a trademark of Maxim Integrated Products, Inc.
+Denotes lead(Pb)-free/RoHS-compliant package.
*EP = Exposed pad.
MAX9701
1.3W, Filterless, Stereo Class D Audio
Power Amplifier
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(VDD= PVDD= SHDN= 3.3V, GND = PGND = 0V, SYNC = 0V(FFM), gain = 6dB (GAIN1 = 0, GAIN2 = 1), RLconnected between
OUT+ and OUT-, RL= ∞, TA= TMINto TMAX, unless otherwise noted. Typical values are at TA= +25°C.) (Notes 1, 2)
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.
VDDto GND..............................................................................6V
VDDto PVDD..........................................................-0.3V to +0.3V
PVDDto PGND.........................................................................6V
GND to PGND.......................................................-0.3V to +0.3V
All Other Pins to GND.................................-0.3V to (VDD+ 0.3V)
Continuous Current In/Out of PVDD, PGND, OUT_.........±800mA
Continuous Input Current (all other pins)..........................±20mA
Duration of OUT_ Short Circuit to GND or PVDD........Continuous
Duration of Short Circuit Between OUT+ and OUT-......Continuous
Continuous Power Dissipation (TA= +70°C)
20-Bump UCSP (derate 10mW/°C above +70°C)...........800mW
24-Pin Thin QFN (derate 20.8mW/°C above +70°C)..1666.7mW
Junction Temperature......................................................+150°C
Operating Temperature Range...........................-40°C to +85°C
Storage Temperature Range.............................-65°C to +150°C
Bump Temperature (soldering) Reflow............................+235°C
Lead Temperature (soldering, 10s).................................+300°C
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITS
GENERAL
Supply Voltage RangeVDDInferred from PSRR test2.55.5V
VDD = 3.3V, per channel4.58Quiescent CurrentIDDVDD = 5V, per channel6.310mA
Shutdown CurrentISHDN0.110μA
Common-Mode Rejection RatioCMRRfIN = 1kHz66dB
Input Bias VoltageVBIAS1.1251.251.375V
Turn-On TimetON40ms
TA = +25oC±10±30
Output Offset VoltageVOS
TMIN < TA < TMAX±55
VDD = 2.5V to 5.5V, VIN = 0V6080
fRIPPLE = 217Hz72Power-Supply Rejection RatioPSRR100mVP-P ripple,
VIN = 0VfRIPPLE = 20kHz50
RL = 8Ω460VDD = 3.3VRL = 4Ω750
RL = 8Ω1300Output Power (Note 3)POUTTHD+N = 1%,
TA = +25oC
VDD = 5VRL = 4Ω2200
RL = 8Ω (POUT = 300mW), f = 1kHz0.08Total Harmonic Distortion Plus
Noise (Note 3)THD+NRL = 4Ω (POUT = 400mW), f = 1kHz0.15%
FFM86BW = 22Hz
to 22kHzSSM86
FFM88.5Signal-to-Noise RatioSNRVOUT = 1VRMS
A-weightedSSM88.5
SYNC = GND95011001250
SYNC = unconnected120014001600
Oscillator FrequencyfOSC
SYNC = VDD1200
±60
kHz
Minimum On-TimetMIN200ns
SYNC Frequency Lock RangefSYNC10001600kHz
MAX9701
1.3W, Filterless, Stereo Class D Audio
Power Amplifier
Note 1:All devices are 100% production tested at +25°C. All temperature limits are guaranteed by design.
Note 2:Testing performed with a resistive load in series with an inductor to simulate an actual speaker load. For RL= 4Ω, L = 33μH.
For RL= 8Ω, L = 68μH.
Note 3:When driving speakers below 4Ωwith large signals, exercise care to avoid violating the absolute maximum rating for continuous
output current.
Note 4:Testing performed with 8Ωresistive load in series with 68μH inductive load connected across the BTL output. Mode transi-
tions are controlled by SHDN. KCPlevel is calculated as: 20 x log[(peak voltage under normal operation at rated power
ELECTRICAL CHARACTERISTICS (continued)
(VDD= PVDD= SHDN= 3.3V, GND = PGND = 0V, SYNC = 0V(FFM), gain = 6dB (GAIN1 = 0, GAIN2 = 1), RLconnected between
OUT+ and OUT-, RL= ∞, TA= TMINto TMAX, unless otherwise noted. Typical values are at TA= +25°C.) (Notes 1, 2)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITS
SYNC_OUT Capacitance DriveCSYNC_OUT100pF
Bridge-tied capacitance200Capacitive DriveCLSingle ended400pF
Into shutdown66.16
Click-and-Pop LevelKCP
Peak reading, TH D + N = 1%
A-weighted, 32 samples
per second (Note 4)Out of
shutdown66.26
VDD = 3.3V, POUT = 500mW per channel,
fIN = 1kHz, RL = 8Ω87
Efficiencyη
VDD = 5V, POUT = 1000mW per channel,
fIN = 1kHz, RL = 8Ω87.4
GAIN1 = 0, GAIN2 = 010.51519.5
GAIN1 = 1, GAIN2 = 025
GAIN1 = 0, GAIN2 = 137.4Input ResistanceRIN
GAIN1 = 1, GAIN2 = 150
GAIN1 = 0, GAIN2 = 018
GAIN1 = 1, GAIN2 = 012
GAIN1 = 0, GAIN2 = 16GainAV
GAIN1 = 1, GAIN2 = 10
Channel-to-Channel Gain
Tracking1%
CrosstalkL to R, R to L, f = 10kHz, RL = 8Ω,
POUT = 300mW70dB
DIGITAL INPUTS (SHDN, SYNC, GAIN1, GAIN2)
Input-Voltage HighVINH2V
Input-Voltage LowVINL0.8V
Input Leakage Current
(SHDN, GAIN1, GAIN2)±1μA
VIN = GND, normal operation-15-7
Input Leakage Current (SYNC)VIN = VDD, normal operation1225μA
DIGITAL OUTPUTS (SYNC_OUT)
Output-Voltage HighVOHIOH = 3mA, VDD = 3.3V2.4V
Output-Voltage LowVOLIOL = 3mA0.08V
MAX9701
1.3W, Filterless, Stereo Class D Audio
Power Amplifier
Typical Operating Characteristics
(VDD= PVDD= SHDN= 3.3V, GND = PGND = 0V, SYNC = VDD(SSM), gain = 6dB (GAIN1 = 0, GAIN2 = 1)).
TOTAL HARMONIC DISTORTION
PLUS NOISE vs. FREQUENCY
MAX9701 toc01
FREQUENCY (Hz)
THD+N (%)
10k1k100
0.01100k
VDD = 5V
RL = 4Ω
OUTPUT POWER = 300mW
OUTPUT POWER = 100mW
OUTPUT POWER = 600mW
TOTAL HARMONIC DISTORTION
PLUS NOISE vs. FREQUENCY
MAX9701 toc02
FREQUENCY (Hz)
THD+N (%)
10k1k100
0.01100k
VDD = 5V
RL = 8Ω
OUTPUT POWER = 250mW
OUTPUT POWER = 100mW
OUTPUT POWER = 500mW
TOTAL HARMONIC DISTORTION
PLUS NOISE vs. FREQUENCY
MAX9701 toc03
FREQUENCY (Hz)
THD+N (%)
10k1k100
0.01100k
VDD = 3.3V
RL = 4Ω
OUTPUT POWER = 300mW
OUTPUT POWER = 100mW
OUTPUT POWER = 600mW
TOTAL HARMONIC DISTORTION
PLUS NOISE vs. FREQUENCY
MAX9701 toc04
FREQUENCY (Hz)
THD+N (%)
10k1k100
0.01100k
VDD = 3.3V
RL = 8Ω
OUTPUT POWER = 100mW
OUTPUT POWER = 400mW
OUTPUT POWER = 250mW
TOTAL HARMONIC DISTORTION
PLUS NOISE vs. FREQUENCY
MAX9701 toc05
FREQUENCY (Hz)
THD+N (%)
10k1k100
0.01100k
VDD = 5V
RL = 8Ω
POUT = 800mW
FFM
SSM
TOTAL HARMONIC DISTORTION
PLUS NOISE vs. OUTPUT POWER
MAX9701 toc06
OUTPUT POWER (W)
THD+N (%)
VDD = 5V
RL = 4Ω
fIN = 10kHz
fIN = 20kHz
fIN = 1kHz
TOTAL HARMONIC DISTORTION
PLUS NOISE vs. OUTPUT POWER
MAX9701 toc07
OUTPUT POWER (W)
THD+N (%)
VDD = 5V
RL = 8Ω
fIN = 10kHz
fIN = 20kHz fIN = 1kHz
TOTAL HARMONIC DISTORTION
PLUS NOISE vs. OUTPUT POWER
MAX9701 toc08
OUTPUT POWER (W)
THD+N (%)
VDD = 3.3V
RL = 4Ω
fIN = 10kHz
fIN = 20kHz
fIN = 1kHz
TOTAL HARMONIC DISTORTION
PLUS NOISE vs. OUTPUT POWER
MAX9701 toc09
OUTPUT POWER (mW)
THD+N (%)
VDD = 3.3V
RL = 8Ω
fIN = 10kHz
fIN = 20kHz
fIN = 1kHz
MAX9701
1.3W, Filterless, Stereo Class D Audio
Power Amplifier
Typical Operating Characteristics (continued)
(VDD= PVDD= SHDN= 3.3V, GND = PGND = 0V, SYNC = VDD(SSM), gain = 6dB (GAIN1 = 0, GAIN2 = 1)).
TOTAL HARMONIC DISTORTION
PLUS NOISE vs. OUTPUT POWER
MAX9701 toc10
OUTPUT POWER (W)
THD+N (%)
VDD = 5V
RL = 8Ω
fIN = 1kHz
SSM
FFM
EFFICIENCY vs. OUTPUT POWER
MAX9701 toc11
OUTPUT POWER (W)
EFFICIENCY (%)
RL = 8Ω
RL = 4Ω
VDD = 5V
fIN = 1kHz
EFFICIENCY vs. OUTPUT POWER
MAX9701 toc12
OUTPUT POWER (W)
EFFICIENCY (%)
RL = 8Ω
RL = 4Ω
VDD = 3.3V
fIN = 1kHz
OUTPUT POWER vs. SUPPLY VOLTAGE
MAX9701 toc13
SUPPLY VOLTAGE (V)
OUTPUT POWER (W)
RL = 4Ω
AV = 12dB
fIN = 1kHz
THD+N = 10%
THD+N = 1%
OUTPUT POWER vs. SUPPLY VOLTAGE
MAX9701 toc14
SUPPLY VOLTAGE (V)
OUTPUT POWER (W)
RL = 8Ω
AV = 12dB
fIN = 1kHz
THD+N = 10%
THD+N = 1%
OUTPUT POWER vs. LOAD RESISTANCE
MAX9701 toc15
LOAD RESISTANCE (Ω)
OUTPUT POWER (W)604020
VDD = 5V
fIN = 1kHz
THD+N = 10%
THD+N = 1%
OUTPUT POWER vs. LOAD RESISTANCE
MAX9701 toc16
LOAD RESISTANCE (Ω)
OUTPUT POWER (W)604020
fIN = 1kHz
THD+N = 10%
THD+N = 1%
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY
MAX9701 toc17
FREQUENCY (Hz)
PSRR (dB)
10k1k100
-100100k
VRIPPLE = 100mVP-P
RL = 8Ω
COMMON-MODE REJECTION RATIO
vs. FREQUENCY
MAX9701 toc18
FREQUENCY (Hz)
CMRR (dB)
10k1k100
-100100k
VCM = 100mVP-P
RL = 8Ω
VDD = 5V
VDD = 3.3V
MAX9701
1.3W, Filterless, Stereo Class D Audio
Power Amplifier
Typical Operating Characteristics (continued)
(VDD= PVDD= SHDN= 3.3V, GND = PGND = 0V, SYNC = VDD(SSM), gain = 6dB (GAIN1 = 0, GAIN2 = 1)).
CROSSTALK vs. FREQUENCY
MAX9701 toc19
FREQUENCY (Hz)
CROSSTALK (dB)
10k1k100
-130100k
RIGHT TO LEFT
LEFT TO RIGHT
POUT = 300mW
RL = 8Ω
CROSSTALK vs. INPUT AMPLITUDE
MAX9701 toc20
INPUT AMPLITUDE (dB)
CROSSTALK (dB)
RL = 8Ω
fIN = 1kHz
RIGHT TO LEFT
LEFT TO RIGHT
OUTPUT FREQUENCY SPECTRUM
MAX9701 toc21
FREQUENCY (Hz)
OUTPUT MAGNITUDE (dBV)
15k10k5k
-14020k
FFM MODE
VOUT = -60dBV
f = 1kHz
RL = 8Ω
UNWEIGHTED
OUTPUT FREQUENCY SPECTRUM
MAX9701 toc22
FREQUENCY (Hz)
OUTPUT MAGNITUDE (dBV)
15k10k5k
-14020k
FFM MODE
VOUT = -60dBV
f = 1kHz
RL = 8Ω
A-WEIGHTED
OUTPUT FREQUENCY SPECTRUM
MAX9701 toc23
FREQUENCY (Hz)
OUTPUT MAGNITUDE (dBV)
15k10k5k
-14020k
SSM MODE
VOUT = -60dBV
f = 1kHz
RL = 8Ω
UNWEIGHTED
OUTPUT FREQUENCY SPECTRUM
MAX9701 toc24
FREQUENCY (Hz)
OUTPUT MAGNITUDE (dBV)
15k10k5k
-14020k
SSM MODE
VOUT = -60dBV
f = 1kHz
RL = 8Ω
A-WEIGHTED
MAX9701
1.3W, Filterless, Stereo Class D Audio
Power Amplifier
WIDEBAND OUTPUT SPECTRUM
(FFM MODE)
MAX9701 toc25
FREQUENCY (Hz)
OUTPUT MAGNITUDE (dB)
100k10k
-1001M
RBW = 10kHz
INPUT AC GROUNDED
WIDEBAND OUTPUT SPECTRUM
(SSM MODE)
MAX9701 toc26
FREQUENCY (Hz)
OUTPUT MAGNITUDE (dB)
100k10k
-1001M
RBW = 10kHz
INPUT AC GROUNDED
TURN-ON/TURN-OFF RESPONSE
MAX9701 toc27
MAX9701
OUTPUT
SHDN
250mV/div
2V/div
10ms/div
SUPPLY CURRENT
vs. SUPPLY VOLTAGE
MAX9701 toc28
SUPPLY VOLTAGE (V)
SUPPLY CURRENT (mA)
SSM
FFM
BOTH CHANNELS
SHUTDOWN CURRENT
vs. SUPPLY VOLTAGE
MAX9701 toc29
SUPPLY VOLTAGE (V)
SHUTDOWN CURRENT (
BOTH CHANNELS
Typical Operating Characteristics (continued)
(VDD= PVDD= SHDN= 3.3V, GND = PGND = 0V, SYNC = VDD(SSM), gain = 6dB (GAIN1 = 0, GAIN2 = 1)).
MAX9701
1.3W, Filterless, Stereo Class D Audio
Power Amplifier
Pin Description
PIN
TQFNUCSPNAMEFUNCTION
1A2SHDNActive-Low Shutdown. Connect to VDD for normal operation.B3SYNC
Frequency Select and External Clock Input.
SYNC = GND: Fixed-frequency mode with fS = 1100kHz.
SYNC = Unconnected: Fixed-frequency mode with fS = 1400kHz.
SYNC = VDD: Spread-spectrum mode with fS = 1200kHz ±60kHz.
SYNC = Clocked: Fixed-frequency mode with fS = external clock frequency.
3, 8, 11, 16—N.C.No Connection. Not internally connected.A3OUTL+Left-Channel Amplifier Output Positive Phase
5, 14A4, D4PVDDH-Bridge Power Supply. Connect to VDD. Bypass with a 0.1μF capacitor to PGND.
6, 13B4, C4PGNDPower GroundA5OUTL-Left-Channel Amplifier Output Negative Phase
9, 22B1, B5GNDAnalog GroundC5SYNC_OUTClock Signal OutputD5OUTR-Right-Channel Amplifier Output Negative PhaseD3OUTR+Right-Channel Amplifier Output Positive PhaseC3GAIN1Gain-Select Input 1D2GAIN2Gain-Select Input 2D1INR-Right-Channel Inverting InputC2INR+Right-Channel Noninverting InputC1VDDAnalog Power Supply. Connect to PVDD. Bypass with a 10μF capacitor to GND.B2INL+Left-Channel Noninverting InputA1INL-Left-Channel Inverting Input—EPExposed Pad. Connect the exposed thermal pad to the GND plane (see the Supply
Bypassing, Layout, and Grounding section).
MAX9701
1.3W, Filterless, Stereo Class D Audio
Power Amplifier
Functional Diagram
VBIAS
VBIAS
CLASS D
MODULATOR
AND H-BRIDGE
CLASS D
MODULATOR
AND H-BRIDGE
BIAS
GENERATOR
OSCILLATOR
AND
SAWTOOTH
GAIN
CONTROL
OUTL+
VBIAS
MAX9701
GNDPGND
OUTR+
OUTL-
OUTR-
SYNC_OUT
PVDD
SYNC
INL+
INL-
INR+
INR-
GAIN1
GAIN2
SHDN
RIN
RIN
RIN
RIN
470nF
470nF
470nF
470nF
VDD
VDD
10μF0.1μF
MAX9701
Detailed Description
The MAX9701 filterless, stereo Class D audio power
amplifier features several improvements to switch-mode
amplifier technology. The MAX9701 offers Class AB per-
formance with Class D efficiency, while occupying mini-
mal board space. A unique, filterless modulation
scheme, synchronizable switching frequency, and
spread-spectrum switching mode create a compact,
flexible, low-noise, efficient audio power amplifier. The
differential input architecture reduces common-mode
noise pickup, and can be used without input-coupling
capacitors. The inputs can also be configured to accept
a single-ended input signal.
Comparators monitor the MAX9701 inputs and compare
the complementary input voltages to the sawtooth wave-
form. The comparators trip when the input magnitude of
the sawtooth exceeds their corresponding input voltage.
Both comparators reset at a fixed time after the rising
edge of the second comparator trip point, generating a
minimum-width pulse (tON(MIN)) at the output of the sec-
ond comparator (Figure 1). As the input voltage increases
or decreases, the duration of the pulse at one output
increases while the other output pulse duration remains
the same. This causes the net voltage across the speaker
(VOUT+- VOUT-) to change. The minimum-width pulse
helps the device to achieve high levels of linearity.
1.3W, Filterless, Stereo Class D Audio
Power Amplifier
OUT+
OUT-
VIN-
VIN+
VOUT+ - VOUT-
tON(MIN)
tSW
Figure 1. MAX9701 Outputs with an Input Signal Applied
Operating Modes
Fixed-Frequency (FFM) Mode
The MAX9701 features two fixed-frequency modes.
Connect SYNC to GND to select a 1.1MHz switching fre-
quency. Leave SYNC unconnected to select a 1.4MHz
switching frequency. The frequency spectrum of the
MAX9701 consists of the fundamental switching frequen-
cy and its associated harmonics (see the Wideband
Output Spectrum (FFM Mode) graph in the Typical
Operating Characteristics). Program the switching fre-
quency so the harmonics do not fall within a sensitive fre-
quency band (Table 1). Audio reproduction is not
affected by changing the switching frequency.
MAX9701
1.3W, Filterless, Stereo Class D Audio
Power Amplifier
VOUT_+ - VOUT_-
tSWtSWtSWtSW
VIN_-
VIN_+
OUT_+
OUT_-
tON(MIN)
Figure 2. MAX9701 Outputs with an Input Signal Applied (SSM Mode)
Table 1. Operating Modes
SYNCMODE
GNDFFM with fOSC = 1100kHz
UnconnectedFFM with fOSC = 1400kHz
VDDSSM with fOSC = 1200kHz ±60kHz
ClockedFFM with fOSC = external clock frequency

Partno	Mfg	Dc	Qty	Available	Descript
MAX9701ETG+T \|MAX9701ETGT	MAXIM	N/a	24045	avai	1.3W, Filterless, Stereo Class D Audio Power Amplifier