MAX9776ETJ+ ,2 x 1.5W, Stereo Class D Audio Subsystem with DirectDrive Headphone AmplifierELECTRICAL CHARACTERISTICS2(V = PV = CPV = 3.3V, V = V = V = 0V, SHDN = V , I C settings (INA gain ..
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MAX9788ETI+ ,14VP-P, Class G Ceramic Speaker Driverfeatures a mono Class G power amplifier♦ Integrated Charge-Pump Power Supply—Nowith an integrated i ..
MAX9788EWP+TG45 ,14VP-P, Class G Ceramic Speaker DriverBlock Diagram2.7V TO 5.5VV CPVCC DDFB+MAX9788RFB+CINRIN+IN+ OUT+CLASS G+OUTPUTIN- OUT-STAGE-RC IN-I ..
MAX9789AETJ+ ,Windows Vista-Compliant, Stereo Class AB Speaker Amplifiers and DirectDrive Headphone AmplifiersELECTRICAL CHARACTERISTICS(V = PV = CPV = HPV = HP_EN = V (MAX9789 only) = +5V, V = V = V = SPKR_EN ..
MB89475 ,F2MC-8L/Low Power/Low Voltage Microcontrollersapplications forconsumer product.2* : F MC stands for FUJITSU Flexible Microcontroller.n
MB89535A ,F2MC-8L/Low Power/Low Voltage MicrocontrollersFUJITSU SEMICONDUCTORDS07-12547-4EDATA SHEET8-bit Original Microcontroller CMOS2F MC-8L MB89530A Se ..
MB89535A ,F2MC-8L/Low Power/Low Voltage MicrocontrollersFEATURES• Wide range of package options• Two types of QFP packages (1 mm pitch, 0.65 mm pitch) • LQ ..
MB89537A , 8-bit Original Microcontroller CMOS, F-2MC-8L MB89530A Series
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MB89537AC , 8-bit Original Microcontroller CMOS, F-2MC-8L MB89530A Series
MAX9776ETJ+
2 x 1.5W, Stereo Class D Audio Subsystem with DirectDrive Headphone Amplifier
General DescriptionThe MAX9775/MAX9776 combine a high-efficiency
Class D, stereo/mono audio power amplifier with a
mono DirectDrive®receiver amplifier and a stereo
DirectDrive headphone amplifier.
Maxim’s 3rd-generation, ultra-low-EMI, Class D audio
power amplifiers provide Class AB performance with
Class D efficiency. The MAX9775/MAX9776 deliver
1.5W per channel into a 4Ωload from a 5V supply and
offer efficiencies up to 79%. Active emissions limiting
circuitry and spread-spectrum modulation greatly
reduce EMI, eliminating the need for output filtering
found in traditional Class D devices.
The MAX9775/MAX9776 utilize a fully differential archi-
tecture, a full-bridged output, and comprehensive click-
and-pop suppression. A 3D stereo enhancement
function allows the MAX9775 to widen the stereo sound
field immersing the listener in a cleaner, richer sound
experience than typically found in portable applications.
The devices utilize a flexible, user-defined mixer archi-
tecture that includes an input mixer, volume control, and
output mixer. All control is done through I2C.
The mono receiver amplifier and stereo headphone
amplifier use Maxim’s DirectDrive architecture that pro-
duces a ground-referenced output from a single supply,
eliminating the need for large DC-blocking capacitors,
saving cost, space, and component height.
The MAX9775 is available in a 36-bump WLP (3mm x
3mm) package. The MAX9776 is available in a 32-pin
TQFN (5mm x 5mm) or a 36-bump WLP (3mm x 3mm)
package. Both devices are specified over the extended
-40°C to +85°C temperature range.
ApplicationsCell Phones
Portable Multimedia Players
Handheld Gaming Consoles
FeaturesUnique Spread-Spectrum Modulation and Active
Emissions Limiting Significantly Reduces EMI3D Stereo Enhancement (MAX9775 Only)Up to 3 Stereo Inputs1.5W Stereo Speaker Output (4Ω, VDD= 5V)50mW Mono Receiver/Stereo Headphone Outputs
(32Ω, VDD= 3.3V)High PSRR (68dB at 217Hz)79% Efficiency (VDD= 3.3V, RL= 8Ω, POUT=
470mW)I2C Control—Input Configuration, Volume Control,
Output ModeClick-and-Pop SuppressionLow Total Harmonic Distortion (0.03% at 1kHz)Current-Limit and Thermal ProtectionAvailable in Space-Saving, 36-Bump WLP (3mm x
3mm) and 32-Pin TQFN (5mm x 5mm) Packages
MAX9775/MAX9776
2 x 1.5W, Stereo Class D Audio Subsystem
with DirectDrive Headphone Amplifier
Ordering InformationMAX9775
MIXER/
MUX
GAIN
CONTROL
SOUND
CONTROL
I2C
INTERFACE
SINGLE SUPPLY 2.7V TO 5.5V
MAX9776
MIXER/
MUX
GAIN
CONTROL
I2C
INTERFACE
SINGLE SUPPLY 2.7V TO 5.5V
Simplified Block Diagrams19-0746; Rev 4; 8/08
Pin Configurations appear at end of data sheet.
PARTPIN-PACKAGECLASS D
AMPLIFIER
MAX9775EBX+T36 WLP*Stereo
MAX9776ETJ+32 TQFN-EP**Mono
MAX9776EBX+T36 WLP*Mono
Note:All devices are specified over the -40°C to +85°C oper-
ating temperature range.
+Denotes a lead-free/RoHS-compliant package.
*Four center bumps depopulated.
**EP = Exposed pad.
DirectDrive is a registered trademark of Maxim Integrated
Products, Inc.
MAX9775/MAX9776
2 x 1.5W, Stereo Class D Audio Subsystem
with DirectDrive Headphone Amplifier
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS(VDD= PVDD= CPVDD= 3.3V, VGND= VPGND= VCPGND= 0V, SHDN= VDD, I2C settings (INA gain = +20dB, INB gain = INC gain =
0dB, volume setting = 0dB, mono path gain = 0dB, SHDN= 1, SSM = 1). Speaker load resistors (RLSP) are terminated between
OUT_+ and OUT_-, headphone load resistors are terminated to GND, unless otherwise noted. C1 = C2 = C3 = 1µF. TA= TMINto
TMAX, unless otherwise noted. Typical values are at TA= +25°C.) (Note 1)
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
PVDDto PGND.........................................................................6V
CPVDDto CPGND....................................................................6V
CPVSSto CPGND.....................................................-6V to +0.3V
VSSto CPGND..........................................................-6V to +0.3V
C1N.......................................(CPVSS- 0.3V) to (CPGND + 0.3V)
C1P.......................................(CPGND - 0.3V) to (CPVDD+ 0.3V)
HPL, HPR to GND...................(CPVSS- 0.3V) to (CPVDD+ 0.3V)
GND to PGND and CPGND................................................±0.3V
VDDto PVDDand CPVDD....................................................±0.3V
SDA, SCL to GND.....................................................-0.3V to +6V
All other pins to GND..................................-0.3V to (VDD+ 0.3V)
Continuous Current In/Out of PVDD, PGND, CPVDD, CPGND,
OUT__, HPR, and HPL..................................................±800mA
Continuous Input Current CPVSS......................................260mA
Continuous Input Current (all other pins).........................±20mA
Duration of Short Circuit Between
OUT_+ and OUT_-..................................................Continuous
Duration of HP_, OUT_ Short Circuit to
GND or PVDD..........................................................Continuous
Continuous Power Dissipation (TA= +70°C)
36-Bump (3mm x 3mm) UCSP Multilayer Board
(derate 17.0mW/°C above +70°C)...........................1360.5mW
32-Pin (5mm x 5mm) TQFN Single-Layer Board
(derate 21.3mW/°C above +70°C)...........................1702.1mW
32-Pin TQFN Multilayer Board (derate 34.5mW/°C
above +70°C)...........................................................2758.6mW
Junction Temperature......................................................+150°C
Operating Temperature Range...........................-40°C to +85°C
Storage Temperature Range.............................-65°C to +150°C
Lead Temperature (soldering, 10s).................................+300°C
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITS
GENERALSupply Voltage RangeVDD, PVDD,
CPVDDInferred from PSRR test2.75.5V
Output mode 1, 6, 11 (Rx mode)6.310
Output mode 4, 9, 14 (HP mode)812.6
Output mode 2, 7, 12 (SP mode)9.515Quiescent Current (Mono)IDD
Output mode 3, 8, 13 (SP and HP mode)12.918
Output mode 1, 6, 11 (Rx mode)7
Output mode 4, 9, 14 (HP mode)9
Output mode 2, 7, 12 (SP mode)16.5Quiescent Current (Stereo)IDD
Output mode 3, 8, 13 (SP and HP mode)20
Mute CurrentIMUTECurrent in mute (low power)4.710mA
Hard shutdownSHDN = GND0.110
Shutdown CurrentISHDNSoft shutdownSee the I2C Interface
section8.515µA
Turn-On TimetONTime from shutdown or power-on to full
operation30ms
B and C pair inputs, TA = +25°C,
VOL = max17.52841.0kΩInput ResistanceRIN
A pair inputs, TA = +25°C, +20dB3.55.58.0kΩ
Common-Mode Rejection RatioCMRRTA = +25°C, fIN = 1kHz (Note 2)455060dB
MAX9775/MAX9776
2 x 1.5W, Stereo Class D Audio Subsystem
with DirectDrive Headphone Amplifier
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITS
SPEAKER AMPLIFIERSTA = +25°C±5.5±23.5Output Offset VoltageVOSTMIN ≤ TA ≤ TMAX±40mV
Into shutdown-62
Out of shutdown-60
Into mute-63Click-and-Pop LevelKCPeak vol tag e,
TA = + 25°C ,
A- w ei g hted , 32
sam p l es p er second N otes 2, 3) Out of mute-62
VDD = 2.7V to 5.5V4870
f = 217Hz,
100mVP-P ripple68
f = 1kHz,
100mVP-P ripple60
Power-Supply Rejection Ratio
(Note 3)PSRRTA = +25°C
f = 20kHz,
100mVP-P ripple50
RL = 4Ω, VDD = 5V1500
RL = 8Ω, VDD = 3.3V450Output Power (Note 4)POUTTHD+N = 1%,
TA = +25°C
RL = 8Ω, VDD = 5V1115
Current Limit1.6A
RL = 8Ω,
POUT = 125mW0.03
Total Harmonic Distortion Plus
Noise (Note 4)THD+Nf = 1kHzRL = 4Ω,
POUT = 250mW0.04
BW = 20Hz to 20kHz81
Signal-to-Noise RatioSNR
VOUT = 1.8VRMS,
RL = 8Ω, 3D not
active (Note 3)A-weighted84
Fixed-frequency modulation1100Output FrequencyfOSCSpread-spectrum modulation1100 ± 30kHz
EfficiencyηPOUT = 470mW, f = 1kHz both channels
driven, L = 68µH in series with 8Ω load79%
GainAV12dB
Channel-to-Channel Gain
Tracking (Note 5)TA = +25°C±1%
3D Sound Resistors (Note 5)R3DUsed with 22nF and 2.2nF external
capacitors579kΩ
Crosstalk (Notes 4, 5)L to R, R to L, f = 10kHz, RL = 8Ω,
VOUT = 300mVRMS73dB
ELECTRICAL CHARACTERISTICS (continued)(VDD= PVDD= CPVDD= 3.3V, VGND= VPGND= VCPGND= 0V, SHDN= VDD, I2C settings (INA gain = +20dB, INB gain = INC gain =
0dB, volume setting = 0dB, mono path gain = 0dB, SHDN= 1, SSM = 1). Speaker load resistors (RLSP) are terminated between
OUT_+ and OUT_-, headphone load resistors are terminated to GND, unless otherwise noted. C1 = C2 = C3 = 1µF. TA= TMINto
TMAX, unless otherwise noted. Typical values are at TA= +25°C.) (Note 1)
MAX9775/MAX9776
2 x 1.5W, Stereo Class D Audio Subsystem
with DirectDrive Headphone Amplifier
ELECTRICAL CHARACTERISTICS (continued)(VDD= PVDD= CPVDD= 3.3V, VGND= VPGND= VCPGND= 0V, SHDN= VDD, I2C settings (INA gain = +20dB, INB gain = INC gain =
0dB, volume setting = 0dB, mono path gain = 0dB, SHDN= 1, SSM = 1). Speaker load resistors (RLSP) are terminated between
OUT_+ and OUT_-, headphone load resistors are terminated to GND, unless otherwise noted. C1 = C2 = C3 = 1µF. TA= TMINto
TMAX, unless otherwise noted. Typical values are at TA= +25°C.) (Note 1)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITS
RECEIVER AMPLIFIEROutput Offset VoltageVOSTA = +25°C±1.8±5.5mV
Into shutdown-62
Into mute-67
Out of shutdown-63Click-and-Pop LevelKCP
Peak voltage, TA =
+25°C, A-weighted,
32 samples per
second (Notes 3, 6)Out of mute-66
VDD = 2.7V to 5.5V5880
f = 217Hz,
100mVP-P ripple80
f = 1kHz,
100mVP-P ripple70
Power-Supply Rejection Ratio
(Note 3)PSRRTA = +25°C
f = 20kHz,
100mVP-P ripple62
RL = 16Ω60Output PowerPOUTTA = +25°C,
THD+N = 1%RL = 32Ω50mW
GainAV3dB
RL = 16Ω (VOUT = 800mVRMS, f = 1kHz)0.03Total Harmonic Distortion Plus
NoiseTHD+NRL = 32Ω (VOUT = 800mVRMS, f = 1kHz)0.024%
BW = 20Hz to 20kHz87Signal-to-Noise RatioSNRRL = 16Ω, VOUT =
800mVRMS (Note 3)A-weighted89dB
Slew RateSR0.3V/µs
Capacitive DriveCL300pF
HEADPHONE AMPLIFIERSOutput Offset VoltageVOSTA = +25°C±1.8±5.5mV
Into shutdown-61
Into mute-65
Out of shutdown-60Click-and-Pop LevelKCP
Peak voltage, TA =
+25°C, A-weighted,
32 samples per
second (Notes 2, 4)Out of mute-64
Contact±4ESD ProtectionHP_Air±8kV
VDD = 2.7V to 5.5V5880
f = 217Hz,
100mVP-P ripple80
f = 1kHz,
100mVP-P ripple70
Power-Supply Rejection Ratio
(Note 3)PSRRTA = +25°C
f = 20kHz,
100mVP-P ripple62
MAX9775/MAX9776
2 x 1.5W, Stereo Class D Audio Subsystem
with DirectDrive Headphone Amplifier
ELECTRICAL CHARACTERISTICS (continued)(VDD= PVDD= CPVDD= 3.3V, VGND= VPGND= VCPGND= 0V, SHDN= VDD, I2C settings (INA gain = +20dB, INB gain = INC gain =
0dB, volume setting = 0dB, mono path gain = 0dB, SHDN= 1, SSM = 1). Speaker load resistors (RLSP) are terminated between
OUT_+ and OUT_-, headphone load resistors are terminated to GND, unless otherwise noted. C1 = C2 = C3 = 1µF. TA= TMINto
TMAX, unless otherwise noted. Typical values are at TA= +25°C.) (Note 1)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITSRL = 16Ω60Output PowerPOUTTA = +25°C,
THD+N = 1%RL = 32Ω50mW
Current Limit170mA
GainAV+3dB
Channel-to-Channel Gain
TrackingTA = +25°C±1%
RL = 16Ω (VOUT = 800mVRMS, f = 1kHz)0.03Total Harmonic Distortion Plus
NoiseTHD+NRL = 32Ω (VOUT = 800mVRMS, f = 1kHz)0.024%
BW = 20Hz to
20kHz92Signal-to-Noise RatioSNRRL = 16Ω,
VOUT = 800mVRMS
A-weighted93
Slew RateSR0.3V/µs
Capacitive DriveCL300pF
CrosstalkL to R, R to L, f = 10kHz, RL = 16Ω,
VOUT = 160mVRMS75dB
VOLUME CONTROLHP gain (max)3
SP gain (max)12
HP gain (min)-72
IN+6dB = 0
(minimum gain
setting)
SP gain (min)-63
HP gain (max)9
SP gain (max)18
HP gain (min)-61
Volume Control
IN+6dB = 1
(maximum gain
setting)
SP gain (min)-57
Mono+6dB = 00
Mono GainAll outputs
Mono+6dB = 16
INA+20dB = 0 (minimum gain setting)Set by IN+6dB
Input Pair A ControlINA+20dB = 1 (maximum gain setting)20dB
Mute Attenuation
(Minimum Volume)VIN = 1VRMS80dB
DIGITAL INPUTS (SHDN, SDA, SCL)Input-Voltage HighVIH1.4V
Input-Voltage LowVIL0.4V
Input Hysteresis (SDA, SCL)VHYS200mV
MAX9775/MAX9776
2 x 1.5W, Stereo Class D Audio Subsystem
with DirectDrive Headphone Amplifier
ELECTRICAL CHARACTERISTICS (continued)(VDD= PVDD= CPVDD= 3.3V, VGND= VPGND= VCPGND= 0V, SHDN= VDD, I2C settings (INA gain = +20dB, INB gain = INC gain =
0dB, volume setting = 0dB, mono path gain = 0dB, SHDN= 1, SSM = 1). Speaker load resistors (RLSP) are terminated between
OUT_+ and OUT_-, headphone load resistors are terminated to GND, unless otherwise noted. C1 = C2 = C3 = 1µF. TA= TMINto
TMAX, unless otherwise noted. Typical values are at TA= +25°C.) (Note 1)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITSSDA, SCL Input CapacitanceCIN10pF
Input Leakage CurrentIIN0.35.0µA
Pulse Width of Spike SuppressedtSP50ns
DIGITAL OUTPUTS (SDA Open Drain)Output Low Voltage SDAVOLISINK = 6mA0.4V
Output Fall Time SDAtOFVH(MIN) to VL(MAX) bus capacitance =
10pF to 400pF, ISINK = 3mA250ns
I2C INTERFACE TIMING (Note 7)Serial Clock FrequencyfSCLDC400kHz
Bus Free Time Between STOP
and START ConditionstBUF1.3µs
START Condition HoldtHD:STA0.6µs
STOP Condition Setup TimetSU:STA0.6µs
Clock Low PeriodtLOW1.3µs
Clock High PeriodtHIGH0.6µs
Data Setup TimetSU:DAT100ns
Data Hold TimetHD:DAT0900ns
Maximum Receive SCL/SDA Rise
TimetR300ns
Maximum Receive SCL/SDA Fall
TimetF300ns
Setup Time for STOP ConditiontSU:STO0.6µs
Capacitive Load for Each Bus
LineCb400pF
Note 1:All devices are 100% production tested at room temperature. All temperature limits are guaranteed by design.
Note 2:Measured at headphone outputs.
Note 3:Amplifier inputs AC-coupled to GND.
Note 4:Testing performed with a resistive load in series with an inductor to simulate an actual speaker load. For RL= 8Ω, L = 68µH;
for RL= 4Ω, L = 47µH.
Note 5:MAX9775 only.
Note 6:Testing performed at room temperature with an 8Ωresistive load in series with a 68µH inductive load connected across BTL
outputs for speaker amplifier. Testing performed with a 32Ωresistive load connected between OUT_ and GND for head-
phone amplifier. Testing performed with 32Ωresistive load connected between OUTRx and GND for mono receiver amplifi-
er. Mode transitions are controlled by I2C.
Note 7:Guaranteed by design.
MAX9775/MAX9776
2 x 1.5W, Stereo Class D Audio Subsystem
with DirectDrive Headphone Amplifier
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCYMAX9775/76 toc01
FREQUENCY (Hz)
THD+N (%)
10k1k100
0.01100k
VDD = 5V
RL = 4Ω
POUT = 400mW
POUT = 1000mW
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCYMAX9775/76 toc02
FREQUENCY (Hz)
THD+N (%)
10k1k100
0.01100k
VDD = 5V
RL = 8Ω
POUT = 150mW
POUT = 750mW
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCYMAX9775/76 toc03
FREQUENCY (Hz)
THD+N (%)
10k1k100
0.01100k
VDD = 3.3V
RL = 4Ω
POUT = 400mW
POUT = 150mW
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCYMAX9775/76 toc04
FREQUENCY (Hz)
THD+N (%)
10k1k100
0.01100k
VDD = 3.3V
RL = 8Ω
POUT = 300mW
POUT = 150mW
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCYMAX9775/76 toc05
FREQUENCY (Hz)
THD+N (%)
10k1k100
0.001100k
SSM
FFM
VDD = 3.3V
RL = 8Ω
POUT = 500mW
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT POWERMAX9775/76 toc06
OUTPUT POWER (W)
THD+N (%)
VDD = 5V
RL = 4Ω
f = 10kHz
f = 20Hz
f = 1kHz
Typical Operating Characteristics(VDD= PVDD= CPVDD= 3.3V, GND = PGND = CPGND = 0V, SHDN= VDD, I2C default gain settings (INA gain = +20dB, INB gain =
INC gain = 0dB, volume setting = 0dB, mono path gain = 0dB, SHDN= 1, SSM = 1). Speaker load resistors (RLSP) are terminated
between OUT_+ and OUT_-, headphone load resistors are terminated to GND, unless otherwise stated. C1 = C2 = C3 = 1µF. TA=
+25°C, unless otherwise noted.)
MAX9775/MAX9776
2 x 1.5W, Stereo Class D Audio Subsystem
with DirectDrive Headphone Amplifier
Typical Operating Characteristics (continued)(VDD= PVDD= CPVDD= 3.3V, GND = PGND = CPGND = 0V, SHDN= VDD, I2C default gain settings (INA gain = +20dB, INB gain =
INC gain = 0dB, volume setting = 0dB, mono path gain = 0dB, SHDN= 1, SSM = 1). Speaker load resistors (RLSP) are terminated
between OUT_+ and OUT_-, headphone load resistors are terminated to GND, unless otherwise stated. C1 = C2 = C3 = 1µF. TA=
+25°C, unless otherwise noted.)
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT POWERMAX9775/76 toc07
OUTPUT POWER (W)
THD+N (%)
VDD = 5V
RL = 8Ω
f = 10kHz
f = 20Hz
f = 1kHz
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT POWERMAX9775/76 toc08
OUTPUT POWER (W)
THD+N (%)
VDD = 3.3V
RL = 4Ω
f = 10kHz
f = 20Hz
f = 1kHz
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT POWERMAX9775/76 toc09
OUTPUT POWER (W)
THD+N (%)
VDD = 3.3V
RL = 8Ω
f = 10kHz
f = 20Hz
f = 1kHz
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT POWERMAX9775/76 toc10
OUTPUT POWER (W)
THD+N (%)
VDD = 5V
RL = 8Ω
f = 1kHz
SSM
FFM
EFFICIENCY
vs. OUTPUT POWERMAX9775/76 toc11
OUTPUT POWER (W)
EFFICIENCY (%)
VDD = 5V
fIN = 1kHz
POUT = POUTL + POUTR
RL = 8Ω
RL = 4Ω
EFFICIENCY
vs. OUTPUT POWERMAX9775/76 toc12
OUTPUT POWER (W)
EFFICIENCY (%)
VDD = 3.3V
fIN = 1kHz
POUT = POUTL + POUTR
RL = 8Ω
RL = 4Ω
MAX9775/MAX9776
2 x 1.5W, Stereo Class D Audio Subsystem
with DirectDrive Headphone Amplifier
Typical Operating Characteristics (continued)(VDD= PVDD= CPVDD= 3.3V, GND = PGND = CPGND = 0V, SHDN= VDD, I2C default gain settings (INA gain = +20dB, INB gain =
INC gain = 0dB, volume setting = 0dB, mono path gain = 0dB, SHDN= 1, SSM = 1). Speaker load resistors (RLSP) are terminated
between OUT_+ and OUT_-, headphone load resistors are terminated to GND, unless otherwise stated. C1 = C2 = C3 = 1µF. TA=
+25°C, unless otherwise noted.)
OUTPUT POWER
vs. SUPPLY VOLTAGEMAX9775/76 toc13
SUPPLY VOLTAGE (V)
OUTPUT POWER (mW)
RL = 4Ω
f = 1kHz
THD+N = 10%
THD+N = 1%
OUTPUT POWER
vs. SUPPLY VOLTAGEMAX9775/76 toc14
SUPPLY VOLTAGE (V)
OUTPUT POWER (mW)
RL = 8Ω
f = 1kHz
THD+N = 10%
THD+N = 1%
OUTPUT POWER
vs. LOADMAX9775/76 toc15
LOAD (Ω)
OUTPUT POWER (W)
THD+N = 10%
THD+N = 1%
VDD = 5V
f = 1kHz
OUTPUT POWER
vs. LOADMAX9775/76 toc16
LOAD (Ω)
OUTPUT POWER (W)
THD+N = 10%
THD+N = 1%
VDD = 3.3V
f = 1kHz
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCYMAX9775/76 toc17
FREQUENCY (Hz)
POWER-SUPPLY REJECTION RATIO (dB)
10k1k100
-100100k
OUTR
OUTL
VDD = 3.3V
VIN = 100mVP-P
RL = 8Ω
CROSSTALK vs. FREQUENCYFREQUENCY (Hz)
CROSSTALK (dB)
MAX9775/6 toc18
-101001k10k100k
LEFT TO RIGHT
RIGHT TO LEFT
OUT_ = 1VP-P
RL = 8Ω
MAX9775/MAX9776
2 x 1.5W, Stereo Class D Audio Subsystem
with DirectDrive Headphone Amplifier
Typical Operating Characteristics (continued)(VDD= PVDD= CPVDD= 3.3V, GND = PGND = CPGND = 0V, SHDN= VDD, I2C default gain settings (INA gain = +20dB, INB gain =
INC gain = 0dB, volume setting = 0dB, mono path gain = 0dB, SHDN= 1, SSM = 1). Speaker load resistors (RLSP) are terminated
between OUT_+ and OUT_-, headphone load resistors are terminated to GND, unless otherwise stated. C1 = C2 = C3 = 1µF. TA=
+25°C, unless otherwise noted.)
CROSSTALK vs. INPUT AMPLITUDEINPUT AMPLITUDE (VRMS)
CROSSTALK (dB)
MAX9775/6 toc190.10.20.30.40.50.6
fIN = 1kHz
RL = 8Ω
GAIN = +12dB
LEFT TO RIGHT
RIGHT TO LEFT
IN-BAND OUTPUT SPECTRUMMAX9775/76 toc20
FREQUENCY (Hz)
OUTPUT MAGNITUDE (dBV)
15k10k5k
-14020k
SSM MODE
RL = 8Ω
VDD = 3.3V
fIN = 1kHz
UNWEIGHTED
IN-BAND OUTPUT SPECTRUMMAX9775/76 toc21
FREQUENCY (Hz)
OUTPUT MAGNITUDE (dBV)
15k10k5k
-14020k
FFM MODE
RL = 8Ω
VDD = 3.3V
fIN = 1kHz
UNWEIGHTED
WIDEBAND OUTPUT SPECTRUM
FIXED-FREQUENCY MODEFREQUENCY (MHz)
OUTPUT MAGNITUDE (dBV)
MAX9775/6 toc22
VDD = 5V
RL = 8Ω
INPUTS AC GROUNDED
WIDEBAND OUTPUT SPECTRUM
SPREAD-SPECTRUM MODEFREQUENCY (MHz)
OUTPUT MAGNITUDE (dBV)
MAX9775 toc23
VDD = 5V
RL = 8Ω
INPUTS AC GROUNDED
MAX9775 SUPPLY CURRENT
vs. SUPPLY VOLTAGEMAX9775/76 toc24
SUPPLY VOLTAGE (V)
SUPPLY CURRENT (mA)
SP MODE
INPUTS AC GROUNDED
OUTPUTS UNLOADED
MAX9775/MAX9776
2 x 1.5W, Stereo Class D Audio Subsystem
with DirectDrive Headphone Amplifier
Typical Operating Characteristics (continued)(VDD= PVDD= CPVDD= 3.3V, GND = PGND = CPGND = 0V, SHDN= VDD, I2C default gain settings (INA gain = +20dB, INB gain =
INC gain = 0dB, volume setting = 0dB, mono path gain = 0dB, SHDN= 1, SSM = 1). Speaker load resistors (RLSP) are terminated
between OUT_+ and OUT_-, headphone load resistors are terminated to GND, unless otherwise stated. C1 = C2 = C3 = 1µF. TA=
+25°C, unless otherwise noted.)
MAX9776 SUPPLY CURRENT
vs. SUPPLY VOLTAGEMAX9775/76 toc25
SUPPLY VOLTAGE (V)
SUPPLY CURRENT (mA)
SP MODE
INPUTS AC GROUNDED
OUTPUTS UNLOADED
SHUTDOWN SUPPLY CURRENT
vs. SUPPLY VOLTAGEMAX9775/76 toc26
SUPPLY VOLTAGE (V)
SUPPLY CURRENT (nA)
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY
MAX9775/76 toc27
FREQUENCY (Hz)
THD+N (%)
10k1k100
0.001100k
VDD = 5V
RL = 32Ω
POUT = 20mW
POUT = 40mW
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCYMAX9775/76 toc28
FREQUENCY (Hz)
THD+N (%)
10k1k100
0.001100k
VDD = 3.3V
RL = 16Ω
POUT = 20mW
POUT = 40mW
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCYMAX9775/76 toc29
FREQUENCY (Hz)
THD+N (%)
10k1k100
0.001100k
VDD = 3.3V
RL = 32Ω
POUT = 10mW
POUT = 40mW
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT POWERMAX9775/76 toc30
OUTPUT POWER (mW)
THD+N (%)4020
VDD = 5V
RL = 32Ω
f = 10kHz
f = 20Hz
f = 1kHz
MAX9775/MAX9776
2 x 1.5W, Stereo Class D Audio Subsystem
with DirectDrive Headphone Amplifier
Typical Operating Characteristics (continued)(VDD= PVDD= CPVDD= 3.3V, GND = PGND = CPGND = 0V, SHDN= VDD, I2C default gain settings (INA gain = +20dB, INB gain =
INC gain = 0dB, volume setting = 0dB, mono path gain = 0dB, SHDN= 1, SSM = 1). Speaker load resistors (RLSP) are terminated
between OUT_+ and OUT_-, headphone load resistors are terminated to GND, unless otherwise stated. C1 = C2 = C3 = 1µF. TA=
+25°C, unless otherwise noted.)
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT POWEROUTPUT POWER (mW)
THD+N (%)
MAX9775 toc31306090120
f = 20Hz
f = 1kHz
f = 10kHz
VDD = 3.3V
RL = 16Ω
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT POWERMAX9775/76 toc32
OUTPUT POWER (mW)
THD+N (%)4020
VDD = 3.3V
RL = 32Ω
f = 10kHz
f = 20Hz
f = 1kHz
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. COMMON-MODE VOLTAGECOMMON-MODE VOLTAGE (V)
THD+N (%)
MAX9775/6 toc330.51.01.52.02.5
VDD = 3.3V
fIN = 1kHz
POUT = 30mW
GAIN = +3dB
RL = 32Ω
POWER DISSIPATION
vs. OUTPUT POWERMAX9775/76 toc34
TOTAL OUTPUT POWER (mW)
POWER DISSIPATION (mW)40
VDD = 5V
f = 1kHz
RL = 32Ω
POUT = POUTR + POUTL
POWER DISSIPATION
vs. OUTPUT POWERMAX9775/76 toc35
TOTAL OUTPUT POWER (mW)
POWER DISSIPATION (mW)
VDD = 3.3V
f = 1kHz
POUT = POUTR + POUTL
RL = 16Ω
RL = 32Ω
OUTPUT POWER
vs. SUPPLY VOLTAGEMAX9775/76 toc36
SUPPLY VOLTAGE (V)
OUTPUT POWER (mW)
THD+N = 10%
THD+N = 1%
RL = 32Ω
f = 1kHz
MAX9775/MAX9776
2 x 1.5W, Stereo Class D Audio Subsystem
with DirectDrive Headphone Amplifier
Typical Operating Characteristics (continued)(VDD= PVDD= CPVDD= 3.3V, GND = PGND = CPGND = 0V, SHDN= VDD, I2C default gain settings (INA gain = +20dB, INB gain =
INC gain = 0dB, volume setting = 0dB, mono path gain = 0dB, SHDN= 1, SSM = 1). Speaker load resistors (RLSP) are terminated
between OUT_+ and OUT_-, headphone load resistors are terminated to GND, unless otherwise stated. C1 = C2 = C3 = 1µF. TA=
+25°C, unless otherwise noted.)
OUTPUT POWER
vs. LOADMAX9775/76 toc37
LOAD (Ω)
OUTPUT POWER (mW)
THD+N = 10%
THD+N = 1%
VDD = 5V
f = 1kHz
OUTPUT POWER
vs. LOADMAX9775/76 toc38
LOAD (Ω)
OUTPUT POWER (mW)
THD+N = 10%
THD+N = 1%
VDD = 3.3V
f = 1kHz
OUTPUT POWER vs. LOAD RESISTANCE
AND CHARGE-PUMP CAPACITOR SIZELOAD (Ω)
OUTPUT POWER (mW)
MAX9775/6 toc39
C1 = C2 = 2.2μF
VDD = 3.3V
f = 1kHz
THD+N = 1%
C1 = C2 = 1μF
C1 = C2 = 0.68μF
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCYFREQUENCY (Hz)
POWER-SUPPLY REJECTION RATIO (dB)
MAX9775/6 toc40
-101001k10k100k
HPL
HPR
VDD = 3.3V
VIN = 100mVP-P
RL = 32Ω
OUTPUT FREQUENCY SPECTRUMMAX9775/76 toc41
FREQUENCY (Hz)
OUTPUT MAGNITUDE (dBV)
15k10k5k
-14020k
VDD = 3.3V
f = 1kHz
RL = 32Ω
CROSSTALK vs. FREQUENCYFREQUENCY (Hz)
CROSSTALK (dB)
MAX9775/6 toc42
-101001k10k100k
OUT_ = 1VP-P
RL = 32Ω
LEFT TO RIGHT
RIGHT TO LEFT
MAX9775/MAX9776
2 x 1.5W, Stereo Class D Audio Subsystem
with DirectDrive Headphone Amplifier
Typical Operating Characteristics (continued)(VDD= PVDD= CPVDD= 3.3V, GND = PGND = CPGND = 0V, SHDN= VDD, I2C default gain settings (INA gain = +20dB, INB gain =
INC gain = 0dB, volume setting = 0dB, mono path gain = 0dB, SHDN= 1, SSM = 1). Speaker load resistors (RLSP) are terminated
between OUT_+ and OUT_-, headphone load resistors are terminated to GND, unless otherwise stated. C1 = C2 = C3 = 1µF. TA=
+25°C, unless otherwise noted.)
CROSSTALK vs. INPUT AMPLITUDEINPUT AMPLITUDE (VRMS)
CROSSTALK (dB)
MAX9775 toc430.40.81.2
fIN = 1kHz
RL = 32Ω
GAIN = +3dB
LEFT TO RIGHT
RIGHT TO LEFT
TURN-ON RESPONSEMAX9775/76 toc44
10ms/div
SCL
2V/div
SPEAKER
OUTPUT
50mA/div
HEADPHONE
OUTPUT
2V/div
TURN-OFF RESPONSEMAX9775/76 toc45
10ms/div
SCL
2V/div
SPEAKER
OUTPUT
50mA/div
HEADPHONE
OUTPUT
2V/div
MUTE-ON RESPONSEMAX9775/76 toc46
10ms/div
SCL
2V/div
SPEAKER
OUTPUT
50mA/div
HEADPHONE
OUTPUT
2V/div
MUTE-OFF RESPONSEMAX9775/76 toc47
10ms/div
SCL
2V/div
SPEAKER
OUTPUT
50mA/div
HEADPHONE
OUTPUT
2V/div
MAX9775/MAX9776
2 x 1.5W, Stereo Class D Audio Subsystem
with DirectDrive Headphone Amplifier
Pin Description—MAX9775
PINNAMEFUNCTIONPVDDClass D Power SupplyOUTL-Negative Left-Speaker OutputSCLSerial Clock Input. Connect a 1kΩ pullup resistor from SCL to VDD.
D1, F3PGNDPower GroundOUTL+Positive Left-Speaker OutputSDASerial Data Input. Connect a 1kΩ pullup resistor from SDA to VDD.CL_L3D External Capacitor 3. Connect a 2.2nF capacitor to GND.CL_H3D External Capacitor 4. Connect a 22nF capacitor to GND.CPVDDCharge-Pump Power SupplyC1PCharge-Pump Flying Capacitor Positive TerminalVBIASCommon-Mode BiasCPGNDCharge-Pump GNDC1NCharge-Pump Flying Capacitor Negative TerminalINC1Input C1. Left input or positive input (see Table 5a).CPVSSCharge-Pump Output. Connect to VSS.HPLLeft Headphone OutputVSSHeadphone Amplifier Negative Power Supply. Connect to CPVSS.HPRRight Headphone OutputINC2Input C2. Right input or negative input (see Table 5a).OUTRxMono Receiver OutputVDDAnalog Power SupplyINB2Input B2. Right input or negative input (see Table 5a).CR_L3D External Capacitor 1. Connect a 2.2nF capacitor to GND.INB1Input B1. Left input or positive input (see Table 5a).GNDAnalog GroundCR_H3D External Capacitor 2. Connect a 22nF capacitor to GND.INA2Input A2. Right input or negative input (see Table 5a).OUTR+Positive Right Speaker OutputINA1Input A1. Left input or positive input (see Table 5a).OUTR-Negative Right Speaker OutputSHDNActive-Low Hardware Shutdown
—EP
Exposed Pad. The external pad lowers the package’s thermal impedance by providing a
direct heat conduction path from the die to the PCB. The exposed pad is internally
connected to GND. Connect the exposed thermal pad to the GND plane.
MAX9775/MAX9776
2 x 1.5W, Stereo Class D Audio Subsystem
with DirectDrive Headphone Amplifier
Pin Description—MAX9776
PIN
TQFNUCSPNAMEFUNCTION1F1PVDDClass D Power SupplyE1OUT-Negative Left-Speaker OutputD2SCLSerial Clock Input. Connect a 1kΩ pullup resistor from SCL to VDD.
4, 29D1, F3PGNDPower GroundC1OUT+Positive Left-Speaker OutputC2SDASerial Data Input. Connect a 1kΩ pullup resistor from SDA to VDD.
7, 8, 23,
26, 28, 31
B1, B2,
E6, F2,
F4, F5
I.C.Internal Connection. Leave unconnected. This pin is internally connected to the signal path.
Do not connect together or to any other pin.A1CPVDDCharge-Pump Power SupplyA2C1PCharge-Pump Flying Capacitor Positive TerminalB3VBIASCommon-Mode BiasA3CPGNDCharge-Pump GNDA4C1NCharge-Pump Flying Capacitor Negative TerminalB4INC1Input C1. Left input or positive input (see Table 5a).A5CPVSSCharge-Pump Output. Connect to VSS.A6HPLLeft Headphone OutputB5VSSHeadphone Amplifier Negative Power Supply. Connect to CPVSS.B6HPRRight Headphone OutputC5INC2Input C2. Right input or negative input (see Table 5a).C6OUTRxMono Receiver OutputD6VDDAnalog Power SupplyD5INB2Input B2. Right input or negative input (see Table 5a).E5INB1Input B1. Left input or positive input (see Table 5a).F6GNDAnalog GroundE4INA2Input A2. Right input or negative input (see Table 5a).E3INA1Input A1. Left input or positive input (see Table 5a).E2SHDNActive-Low Hardware Shutdown—EP
Exposed Pad. The external pad lowers the package’s thermal impedance by providing a
direct heat conduction path from the die to the PCB. The exposed pad is internally connected
to GND. Connect the exposed thermal pad to the GND plane.
MAX9775/MAX9776
2 x 1.5W, Stereo Class D Audio Subsystem
with DirectDrive Headphone Amplifier
Typical Application CircuitsMAX9775
CHARGE
PUMP
VDD
1μF10kΩ
1μF
13 (A4)
12 (A3)
10 (A2)
9 (A1)
C1N
VBIAS
CPGND
INPUT A: 0dB,
6dB, OR 20dB
C1P
30 (E3)
27 (E4)
1μF
1μF
CPVDD
1μF
6 (C2)
3 (D2)
INA2
INA1
INPUT B: 0dB
OR 6dB
MAXIM 3D
SOUND
24 (E5)
22 (D5)
1μF
1μF
INB2
INB1
CLASS D
AMPLIFIER
INPUT C: 0dB
OR 6dB
14 (B4)
19 (C5)
1μF
1μF
INC2
INC1
INPUT
MIXER
OUTPUT
MIXER
RIGHT
VOLUME
LEFT
VOLUME
MONO
VOLUME
11 (B3)
32 (E2)
SDA
SCL
SHDN
I2C CONTROL
3dB
3dB
3dB
DirectDrive
12dB
CLASS D
AMPLIFIER
12dB
OUTR-
OUTRx
HPR
OUTR+
CL_H
22nF
OUTL-
OUTL+
HPL
31 (F2)
20 (C6)
18 (B6)
28 (F4)
2 (E1)
5 (C1)
16 (A6)
3D CIRCUIT
8 (B2)
CL_L
2.2nF
7 (B1)
CR_H
22nF
26 (F5)
CR_L
2.2nF
23 (E6)25 (F6)
GND
4 (D1)29 (F3)
PGNDPGND
1μF
15 (A5)17 (B5)
CPVSSVSS
1μF
21 (D6)
VDD
VDD
1μF0.1μF
1 (F1)
PVDD
VDD
MAX9775/MAX9776
2 x 1.5W, Stereo Class D Audio Subsystem
with DirectDrive Headphone Amplifier
Typical Application Circuits (continued)MAX9776
CHARGE
PUMP
VDD
1μF
1μF
13 (A4)
12 (A3)
10 (A2)
9 (A1)
C1N
VBIAS
CPGND
INPUT A: 0dB,
6dB, OR 20dB
C1P
30 (E3)
27 (E4)
1μF
1μF
CPVDD
1μF
6 (C2)
3 (D2)
INA2
INA1
INPUT B: 0dB
OR 6dB
24 (E5)
22 (D5)
1μF
1μF
INB2
INB1
CLASS D
AMPLIFIERINPUT C: 0dB
OR 6dB
14 (B4)
19 (C5)
1μF
1μF
INC2
INC1
INPUT
MIXER
OUTPUT
MIXER
RIGHT
VOLUME
LEFT
VOLUME
MONO
VOLUME
11 (B3)
32 (E2)
SDA
SCL
SHDN2C CONTROL
3dB
3dB
3dB
DirectDrive
12dB
OUTRx
HPR
OUT-
OUT+
HPL
20 (C6)
18 (B6)
2 (E1)
5 (C1)
16 (A6)
25 (F6)
GND
4 (D1)29 (F3)
PGNDPGND
1μF
15 (A5)17 (B5)
CPVSSVSS
1μF
21 (D6)
VDD
VDD
1μF0.1μF
1 (F1)
PVDD
VDD
10kΩ
MAX9775/MAX9776
2 x 1.5W, Stereo Class D Audio Subsystem
with DirectDrive Headphone AmplifierOUT+
OUT-
VIN-
VIN+
VOUT+ - VOUT-
tON(MIN)
tSW
Detailed DescriptionThe MAX9775/MAX9776 ultra-low-EMI, filterless, Class D
audio power amplifiers feature several improvements to
switch-mode amplifier technology. The MAX9775/
MAX9776 feature active emissions limiting circuitry to
reduce EMI. Zero dead-time technology maintains state-
of-the-art efficiency and THD+N performance by allowing
the output FETs to switch simultaneously without cross-
conduction. A unique filterless modulation scheme and
spread-spectrum modulation create compact, flexible,
low-noise, efficient audio power amplifiers while
occupying minimal board space. The differential input
architecture reduces common-mode noise pickup with or
without the use of input-coupling capacitors. The
MAX9775/MAX9776 can also be configured as single-
ended input amplifiers without performance degradation.
The MAX9775/MAX9776 feature three fully differential
input pairs (INA_, INB_, INC_) that can be configured
as stereo single-ended or mono differential inputs. I2C
provides control for input configuration, volume level,
and mixer configuration. The MAX9775’s 3D enhance-
ment feature widens the stereo sound field to improve
stereo imaging when stereo speakers are placed in
close proximity.
DirectDrive allows the headphone and mono receiver
amplifiers to output ground-referenced signals from a
single supply, eliminating the need for large DC-block-
ing capacitors. Comprehensive click-and-pop suppres-
sion minimizes audible transients during the turn-on
and turn-off of amplifiers.
Class D Speaker AmplifierComparators monitor the audio inputs and compare the
complementary input voltages to a sawtooth waveform.
The comparators trip when the input magnitude of the
sawtooth exceeds their corresponding input voltage. The
active emissions limiting circuitry slightly reduces the
turn-on rate of the output H-bridge by slew-rate limiting
the comparator output pulse. Both comparators reset at
a fixed time after the rising edge of the second compara-
tor trip point, generating a minimum-width pulse
(tON(MIN),100ns typ) at the output of the second com-
parator (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 speak-
er (VOUT+- VOUT-) to change. The minimum-width pulse
helps the devices to achieve high levels of linearity.
