Stereo Audio w/Class G Headphone Amp & Class D Speaker Amp w/Speaker Protection

41 Pages·2017·8.13 MB·English

LM49251
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LM49251 Stereo Audio Subsystem with Class G
Headphone Amplifier and Class D Speaker Amplifier with Speaker Protection
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FEATURES DESCRIPTION
1
• ClassGGroundReferencedHeadphone The LM49251 is a fully integrated audio subsystem
2 designed for portable handheld applications such as
Outputs
cellular phones. Part of TI’s PowerWise family of
• E2SClassDAmplifier
products, the LM49251 utilizes a high efficiency class
• NoClipFunction G headphone amplifier topology as well as a high
• PowerLimiter SpeakerProtection efficiencyclassDloudspeaker.
• I2CVolumeand ModeControl TheheadphoneamplifiersfeatureTI’sclassGground
referenced architecture that creates a ground-
• AdvancedClick-and-PopSuppression
referenced output with dynamic supply rails for
• Micro-PowerShutdown
optimum efficiency. The stereo class D speaker
amplifier provides both a no-clip feature and speaker
APPLICATIONS
protection. The Enhanced Emission Suppression
(E2S) outputs feature a patented, ultra low EMI PWM
• FeaturePhones
architecturethat significantlyreducesRFemissions.
• SmartPhones
The LM49251 features separate volume controls for
KEY SPECIFICATIONS the mono and stereo inputs. Mode selection,
shutdown control, and volume are controlled through
• ClassGHeadphoneAmplifier,HPVDD=1.8V, anI2Ccompatibleinterface.
R =32Ω
L
Click and pop suppression eliminates audible
– IDDQ :1.15mA(Typ)
HP transients on power-up/down and during shutdown.
– Output Power,THD+N ≤ 1%:20mW(Typ) The LM49251 is available in an ultra-small 30-bump
• Stereo ClassDSpeakerAmplifier R =8Ω DSBGApackage(2.55mmx3.02mm)
L
– OutputPower,THD+N≤1%,LSV =5.0V:
DD
1.37W(Typ)
– Output Power,THD+N ≤ 1%,LSV =3.6V:
DD
680mW(Typ)
– Efficiency:90%(Typ)
1
Pleasebeawarethatanimportantnoticeconcerningavailability,standardwarranty,anduseincriticalapplicationsof
TexasInstrumentssemiconductorproductsanddisclaimerstheretoappearsattheendofthisdatasheet.
Alltrademarksarethepropertyoftheirrespectiveowners.
2
PRODUCTIONDATAinformationiscurrentasofpublicationdate. Copyright©2011–2013,TexasInstrumentsIncorporated
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarilyincludetestingofallparameters.
LM49251
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Simplified Block Diagram
D
Mono Input and
Volume Control STEREO
ALC
MIXER D
AND
OUTPUT
Stereo Input
and Volume MODE
Control SELECT
Charge
Pump
+
Class G
2
IC
INTERFACE
Figure1. LM49251SimplifiedBlockDiagram
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Typical Application
VDD
4.7 µF 4.7 µF 4.7 µF
VDD VDD VDD
B1 A4 F4
0.22 µF
INM+ A3
F5 LSOUTL+
VOLUME CLASS D
INM- B3 -86 dB to +12 dB +12 dB, E5 LSOUTL-
ALC +18 dB
0.22 µF POWER
LIMITER
AND
NO
CLIP
A5 LSOUTR+
CLASS D
+12 dB, B5 LSOUTR-
LIN1 D3 MIXER +18 dB
AND
0.22 µF OUTPUT
MODE E4 SET
SELECT
RIN1 C3
100 nF
INL1/INL2
0.22 µF VOLUME
MUX -80 dB to
LIN2 C4 INR1/INR2 +18 dB
-18 dB E1 HPL
to 0 dB
0.22 µF
RIN2 B4
0.22 µF -18 dB D1
to 0 dB HPR
BYPASS D4
BIAS E3
HP GND Sense
2.2 µF
F2 HPVDD
2 C1 CPVDD
ICVDD A1 LEVELA NDDETECT 2.2 µF
SDA B2 I2C INTERFACE CLASS G CHARGE 2.2 µF
CONTROL
SCL C2 PUMP
A2 C5 D5 F3 D2 E2 F1
GND GND GND CPVSS C1- C1+ CPGND
2.2 µF
2.2 µF
Figure2. TypicalAudioAmplifierApplicationCircuit
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Connection Diagram
TopView
Figure3. DSBGAPackage
SeePackageNumber YZR0030
Table1.BumpDescription
Bump Name Description
A1 I2CV I2CPowerSupply
DD
A2 GND Ground
A3 INM+ MonoChannelNon-InvertingInput
A4 V LoudspeakerPowerSupply
DD
A5 LSOUTR+ RightLoudspeakerNon-InvertingOutput
B1 V LoudspeakerPowerSupply
DD
B2 SDA I2CSerialDataInput
B3 INM- MonoChannelInvertingInput
B4 RIN2 RightChannelInput2
B5 LSOUTR- RightLoudspeakerInvertingOutput
C1 CPV ChargePumpSupply(internallygenerated)
DD
C2 SCL I2CSerialClockInput
C3 RIN1 RightChannelInput1
C4 LIN2 LeftChannelInput2
C5 GND Ground
D1 HPR RightChannelHeadphoneOutput
D2 C1- ChargePumpFlyingCapacitorNegativeTerminal
D3 LIN1 LeftChannelInput1
D4 BYPASS Mid-RailBiasBypassNode
D5 GND Ground
E1 HPL LeftChannelHeadphoneOutput
E2 C1+ ChargePumpFlyingCapacitorPositiveTerminal
E3 HPSENSEGND HeadphoneGroundSense
E4 SET ALCTimingSet
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Table1.BumpDescription(continued)
Bump Name Description
E5 LSOUTL- LeftLoudspeakerInvertingOutput
F1 CPGND ChargePumpGround
F2 HPV HeadphonePowerSupply
DD
F3 CPV ChargePumpOutput
SS
F4 V LoudspeakerPowerSupply
DD
F5 LSOUTL+ LeftLoudspeakerNon-InvertingOutput
Thesedeviceshavelimitedbuilt-inESDprotection.Theleadsshouldbeshortedtogetherorthedeviceplacedinconductivefoam
duringstorageorhandlingtopreventelectrostaticdamagetotheMOSgates.
Absolute Maximum Ratings(1)(2)(3)
V ,I2CV 6V
SupplyVoltage(1) DD DD
HPV 3V
DD
StorageTemperature −65°Cto+150°C
InputVoltage −0.3VtoV +0.3V
DD
PowerDissipation(4) InternallyLimited
ESDHBM(5) 2000V
ESDMM(6) 150V
ESDCDM(7) 750V
JunctionTemperature 150°C
ThermalResistance θ (TLA30B1A) 90°C/W
JA
SolderingInformation:SeeAN-1112(LiteratureNumberSNVA009)
(1) AbsoluteMaximumRatingsindicatelimitsbeyondwhichdamagetothedevicemayoccur,includinginoperabilityanddegradationof
devicereliabilityand/orperformance.Functionaloperationofthedeviceand/ornon-degradationattheAbsoluteMaximumRatingsor
otherconditionsbeyondthoseindicatedintheRecommendedOperatingConditionsisnotimplied.TheRecommendedOperating
Conditionsindicateconditionsatwhichthedeviceisfunctionalandthedeviceshouldnotbeoperatedbeyondsuchconditions.All
voltagesaremeasuredwithrespecttothegroundpin,unlessotherwisespecified
(2) TheElectricalCharacteristicstableslistspecifiedspecificationsunderthelistedRecommendedOperatingConditionsexceptas
otherwisemodifiedorspecifiedbytheElectricalCharacteristicsConditionsand/orNotes.Typicalspecificationsareestimationsonlyand
arenotensured.
(3) IfMilitary/Aerospacespecifieddevicesarerequired,pleasecontacttheTexasInstrumentsSalesOffice/Distributorsforavailabilityand
specifications.
(4) ThemaximumpowerdissipationmustbederatedatelevatedtemperaturesandisdictatedbyT ,θ ,andtheambienttemperature,
JMAX JA
T .ThemaximumallowablepowerdissipationisP =(T -T )/θ orthenumbergiveninAbsoluteMaximumRatings,
A DMAX JMAX A JA
whicheverislower.
(5) Humanbodymodel,applicablestd.JESD22-A114C.
(6) Machinemodel,applicablestd.JESD22-A115-A.
(7) Chargedevicemodel,applicablestd.JESD22–C101D.
Operating Ratings
TemperatureRange(T ≤T ≤T ) −40°C≤T ≤+85°C
MIN A MAX A
V 2.7V≤V ≤5.5V
DD DD
SupplyVoltage HPV 1.6V≤HPV ≤2.0V
DD DD
I2C 1.7V≤I2CV ≤5.5V
DD DD
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Electrical Characteristics(1)(2)(3)
ThefollowingspecificationsapplyforA =0dB,R =15μH+8Ω+15μH(Loudspeaker),R =32Ω(Headphone),C =100nF,f
V L L SET
=1kHz,ALCoff,unlessotherwisespecified.LimitsapplyforT =25°C.
A
LM49251 Units
Parameter TestConditions
Typ(4) Limit(5) (Limits)
V =0,NoLoad
IN
LSMode(stereoinput),mode2 5.6 6.25 mA(max)
LSMode(monoinput),mode3 5.3 6.0 mA(max)
QuiescentPowerSupplyCurrent HPMode(stereoinput),mode6 2.1 2.4 mA(max)
I
DD (LSVDD+VDD) HPMode(monoinput),mode4 1.8 2.0 mA(max)
LS+HPMode(stereoinput),mode8 6.1 6.8 mA(max)
LS+HPMode(monoinput),mode5 5.8 6.5 mA(max)
LSMode(stereoinput,ALCon),mode2 5.9
QuiescentPowerSupplyCurrent
V =0,NoLoad,Mode6 1.15 1.45 mA(max)
(HPV ) IN
DD
P =0.5mW,GAMP_SD=0,
IDD OUT 4.3 4.6 mA(max)
(HP) OperatingPowerSupplyCurrent RL=32Ω,Mode6
(HPVDD) POUT=1mW,GAMP_SD=0, 5.8 6.15 mA(max)
R =32Ω,Mode6
L
I ShutdownCurrent 0.02 1 μA(max)
SD
V =0
IN
Mode3,monoinput,A =6dB 12 mV(max)
V
V OutputOffsetVoltage Mode4,monoinput 1.1 mV(max)
OS
Mode2,stereoinput,A =6dB 12 mV(max)
V
Mode6,stereoinput 1.1 mV(max)
HPmode,C =2.2μF
BYPASS
T WakeUpTime Normalturnontime 31 ms
WU
Fastturnontime 16 ms
MinimumGainSetting(monoinput), dB(max)
–86
Mode3 dB(min)
MaximumGainSetting(monoinput), 13 dB(max)
12
Mode3 11.5 dB(min)
A VolumeControl
VOL
MinimumGainSetting(stereoinput), dB(max)
–80
Mode6 dB(min)
MaximumGainSetting(stereoinput), 19 dB(max)
18
Mode6 17.5 dB(min)
VolumeControlStepError ±0.2 dB
(1) AbsoluteMaximumRatingsindicatelimitsbeyondwhichdamagetothedevicemayoccur,includinginoperabilityanddegradationof
devicereliabilityand/orperformance.Functionaloperationofthedeviceand/ornon-degradationattheAbsoluteMaximumRatingsor
otherconditionsbeyondthoseindicatedintheRecommendedOperatingConditionsisnotimplied.TheRecommendedOperating
Conditionsindicateconditionsatwhichthedeviceisfunctionalandthedeviceshouldnotbeoperatedbeyondsuchconditions.All
voltagesaremeasuredwithrespecttothegroundpin,unlessotherwisespecified
(2) TheElectricalCharacteristicstableslistspecifiedspecificationsunderthelistedRecommendedOperatingConditionsexceptas
otherwisemodifiedorspecifiedbytheElectricalCharacteristicsConditionsand/orNotes.Typicalspecificationsareestimationsonlyand
arenotensured.
(3) LoudspeakerR isaresistiveloadinserieswithtwoinductorstosimulateanactualspeakerload.ForR =8Ω,theloadis15μH+8Ω
L L
+15μH.ForR =4Ω,theloadis15μH+4Ω+15μH.
L
(4) TypicalvaluesrepresentmostlikelyparametricnormsatT =+25ºC,andattheRecommendedOperationConditionsatthetimeof
A
productcharacterizationandarenotensured.
(5) Datasheetmin/maxspecificationlimitsareensuredbytestorstatisticalanalysis.
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Electrical Characteristics(1)(2)(3) (continued)
ThefollowingspecificationsapplyforA =0dB,R =15μH+8Ω+15μH(Loudspeaker),R =32Ω(Headphone),C =100nF,f
V L L SET
=1kHz,ALCoff,unlessotherwisespecified.LimitsapplyforT =25°C.
A
LM49251 Units
Parameter TestConditions
Typ(4) Limit(5) (Limits)
LSMode
11.5 dB(min)
Gain0 12
12.5 dB(max)
17.5 dB(min)
Gain1 18
19 dB(max)
HPMode
–0.5 dB(min)
Gain0 0
0.5 dB(max)
AV Gain Gain1 –1.7 dB
Gain2 –3 dB
Gain3 –6 dB
Gain4 –9 dB
Gain5 –12 dB
Gain6 –15 dB
–18.5 dB(min)
Gain7 –18
–17.5 dB(max)
LSOutput –93 dB
A MuteAttenuation
V(MUTE) HPOutput –98 dB
MONO,R ,L inputs
IN IN
9.5 kΩmin)
MaximumGainSetting 13
R InputResistance 15.5 kΩ(max)
IN
97 kΩ(min)
MinimumGainSetting 110
122 kΩ(max)
Mode3,A =18dB,R =8Ω
V L
LSV =3.3V 570 mW
DD
LSV =3.6V 680 600 mW(min)
DD
LSV =4.2V 955 mW
DD
P OutputPower
O
LSV =5.0V 1370 mW
DD
Mode6
R =16Ω 20 mW
L
R =32Ω 20 16 mW(min)
L
f=1kHz,Mode3
0.02 %
MonoInput,P =250mW
O
THD+N TotalHarmonicDistortion+Noise
f=1kHz,Mode6
0.02 %
StereoInput,P =12mW
O
f=217Hz,V =200mV ,InputsACGND,C =2.2μF
RIPPLE P-P B
Mode3,monoinput,A =6dB 77 dB
V
Mode2,stereoinput,A =6dB 65 dB
V
PSRR PowerSupplyRejectionRatio Mode4,rippleonV ,monoinput 93 dB
DD
Mode4,rippleonHPV ,monoinput 83 dB
DD
Mode6,rippleonV ,stereoinput 80 dB
DD
Mode6,rippleonHPV ,stereoinput 80 dB
DD
V =1V ,f =217Hz,monoinput
RIPPLE P-P RIPPLE
CMRR CommonModeRejectionRatio Mode3 52 dB
Mode4 63 dB
η Efficiency LSMode,P =680mW 90 %
O
X Crosstalk P =12mW,f=1kHz,Mode6 84 dB
TALK O
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Electrical Characteristics(1)(2)(3) (continued)
ThefollowingspecificationsapplyforA =0dB,R =15μH+8Ω+15μH(Loudspeaker),R =32Ω(Headphone),C =100nF,f
V L L SET
=1kHz,ALCoff,unlessotherwisespecified.LimitsapplyforT =25°C.
A
LM49251 Units
Parameter TestConditions
Typ(4) Limit(5) (Limits)
A-weighted,InputsACGND
Mode3,monoinput 44 μV
∈ OutputNoise Mode2,stereoinput 45 μV
OS
Mode4,monoinput 8 μV
Mode6,stereoinput 10.2 μV
Mode3,P =680mW 94 dB
SNR Signal-To-Noise-Ratio O
Mode6,P =20mW 98 dB
O
t AttackTime Step1,Mode1 0.75 ms
A
t ReleaseTime Step1,Mode1 1 s
R
Mode3,THD+N≤1%(6)
VoltageLevel
Step1001 3.9 V
P-P
VLIMIT OutputVoltageLimit Step2010 4.7 VP-P
Step3011 5.4 V
P-P
Step4100 6.2 V
P-P
Step5101 7.0 V
P-P
Step6110 7.8 V
P-P
(6) TheLM49251ALClimitstheoutputpowertowhicheverislower,thesupplyvoltageoroutputpowerlimit.
I2C Interface Characteristics V = 5V, 2.2V ≤ I2CV ≤ 5.5V(1)(2)
DD DD
ThefollowingspecificationsapplyforA =0dB,R =8Ω,f=1kHz,unlessotherwisespecified.LimitsapplyforT =25°C.
V L A
LM49251 Units
Parameter TestConditions
Typ(3) Limit(4) (Limits)
t SCLPeriod 2.5 μs(min)
1
t SDASet-upTime 100 ns(min)
2
t SDAStableTime 0 ns(min)
3
t StartConditionTime 100 ns(min)
4
t StopConditionTime 100 ns(min)
5
t SDAHoldtime 100 ns(min)
6
V InputHighVoltage 0.7*I2CV V(min)
IH DD
V InputLowVoltage 0.3*I2CV V(max)
IL DD
(1) AbsoluteMaximumRatingsindicatelimitsbeyondwhichdamagetothedevicemayoccur,includinginoperabilityanddegradationof
devicereliabilityand/orperformance.Functionaloperationofthedeviceand/ornon-degradationattheAbsoluteMaximumRatingsor
otherconditionsbeyondthoseindicatedintheRecommendedOperatingConditionsisnotimplied.TheRecommendedOperating
Conditionsindicateconditionsatwhichthedeviceisfunctionalandthedeviceshouldnotbeoperatedbeyondsuchconditions.All
voltagesaremeasuredwithrespecttothegroundpin,unlessotherwisespecified
(2) TheElectricalCharacteristicstableslistspecifiedspecificationsunderthelistedRecommendedOperatingConditionsexceptas
otherwisemodifiedorspecifiedbytheElectricalCharacteristicsConditionsand/orNotes.Typicalspecificationsareestimationsonlyand
arenotensured.
(3) TypicalvaluesrepresentmostlikelyparametricnormsatT =+25ºC,andattheRecommendedOperationConditionsatthetimeof
A
productcharacterizationandarenotensured.
(4) Datasheetmin/maxspecificationlimitsareensuredbytestorstatisticalanalysis.
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I2C Interface Characteristics V = 5V, 1.8V ≤ I2CV ≤ 2.2V(1)(2)
DD DD
ThefollowingspecificationsapplyforA =0dB,R =8Ω,f=1kHz,unlessotherwisespecified.LimitsapplyforT =25°C.
V L A
LM49251 Units
Parameter TestConditions
Typ(3) Limit(4) (Limits)
t SCLPeriod 2.5 μs(min)
1
t SDASet-upTime 250 ns(min)
2
t SDAStableTime 0 ns(min)
3
t StartConditionTime 250 ns(min)
4
t StopConditionTime 250 ns(min)
5
t SDAHoldTime 250 ns(min)
6
V DigitalInputHighVoltage 0.7*I2CV V(min)
IH DD
V DigitalInputLowVoltage 0.3*I2CV V(max)
IL DD
(1) AbsoluteMaximumRatingsindicatelimitsbeyondwhichdamagetothedevicemayoccur,includinginoperabilityanddegradationof
devicereliabilityand/orperformance.Functionaloperationofthedeviceand/ornon-degradationattheAbsoluteMaximumRatingsor
otherconditionsbeyondthoseindicatedintheRecommendedOperatingConditionsisnotimplied.TheRecommendedOperating
Conditionsindicateconditionsatwhichthedeviceisfunctionalandthedeviceshouldnotbeoperatedbeyondsuchconditions.All
voltagesaremeasuredwithrespecttothegroundpin,unlessotherwisespecified
(2) TheElectricalCharacteristicstableslistspecifiedspecificationsunderthelistedRecommendedOperatingConditionsexceptas
otherwisemodifiedorspecifiedbytheElectricalCharacteristicsConditionsand/orNotes.Typicalspecificationsareestimationsonlyand
arenotensured.
(3) TypicalvaluesrepresentmostlikelyparametricnormsatT =+25ºC,andattheRecommendedOperationConditionsatthetimeof
A
productcharacterizationandarenotensured.
(4) Datasheetmin/maxspecificationlimitsareensuredbytestorstatisticalanalysis.
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Typical Performance Characteristics
THD+NvsFrequency THD+NvsFrequency
V =3.6V,R =15μH+8Ω+15μH V =3.6V,R =15μH+8Ω+15μH
DD L DD L
P =450mW,Mode2 P =450mW,Mode3
OUT OUT
10 10
5 5
2 2
1 1
0.5 0.5
)% )%
( N+ 00..12 ( N+ 00..12
D D
H 0.05 H 0.05
T T
0.02 0.02
0.01 0.01
0.005 0.005
0.002 0.002
0.001 0.001
20 50 100200 500 1k 2k 5k 10k20k 20 50 100200 500 1k 2k 5k 10k20k
FREQUENCY (Hz) FREQUENCY (Hz)
Figure4. Figure5.
THD+NvsFrequency THD+NvsFrequency
V =3.6V,R =15μH+4Ω+15μH V =3.6V,R =15μH+4Ω+15μH
DD L DD L
P =650mW,Mode2 P =650mW,Mode3
OUT OUT
10 10
5 5
2 2
1 1
0.5 0.5
)% )%
( N+ 00..12 ( N+ 00..12
D D
H 0.05 H 0.05
T T
0.02 0.02
0.01 0.01
0.005 0.005
0.002 0.002
0.001 0.001
20 50 100200 500 1k 2k 5k 10k20k 20 50 100200 500 1k 2k 5k 10k20k
FREQUENCY (Hz) FREQUENCY (Hz)
Figure6. Figure7.
THD+NvsFrequency THD+NvsFrequency
V =5V,R =15μH+4Ω+15μH V =5V,R =15μH+4Ω+15μH
DD L DD L
P =1.2W,Mode2 P =1.2W,Mode3
OUT OUT
10 10
5 5
2
1 2
0.5 1
0.2 0.5
)% 0.1 )%
( N+D 00..0052 ( N+D 00..12
H 0.01 H 0.05
T T
0.005
0.02
0.002 0.01
0.001
0.005
0.0005
0.0002 0.002
0.0001 0.001
20 50 100200 500 1k 2k 5k 10k20k 20 50 100200 500 1k 2k 5k 10k20k
FREQUENCY (Hz) FREQUENCY (Hz)
Figure8. Figure9.
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