MAX98310EWL

19-5912; Rev 0; 6/11 EVALUATION KIT AVAILABLE MAX98309/MAX98310 Mono 1.4W Class AB Audio Amplifiers General Description The MAX98309/MAX98310 mono 1.4W class AB audio amplifiers offer low quiescent current while maintaining excellent SNR and low 0.008% THD+N. These ICs feature excellent 90dB PSRR and state of the art click-andpop suppression. The ICs are offered with an internally fixed 0dB, 3dB, 6dB, and 9dB gain (MAX98310) or an externally set gain (MAX98309) through external resistors. The MAX98309 feature a 10ms or 100ms pin-selectable turn-on time, while the MAX98310 has a preset 5ms turnon time. The MAX98309/MAX98310 are available in a (1.0mm x 1.0mm) 9-bump, 0.3mm pitch WLP, and are specified over the extended -40NC to +85NC temperature range. Benefits and Features S EnhancesSystemPerformance  DifferentialInputImprovesNoiseImmunity  Industry-LeadingClick-and-PopSuppression  High90dBPSRR(fIN=217Hz) S SmallerSolutionSize  1mmx1mmWLPFootprint S ExtendsBatteryLife  LowQuiescentCurrent S DeliversRobustSystemDesign  ThermalOverloadProtection  Short-CircuitProtection S 1.2mASupplyCurrent(VDD=3.7V) S 750mWinto8I(VDD=3.7V) S 2.5Vto5.5VSupplyOperation S Pin-Selectable,Internally-FixedGain(MAX98310) S 1.8VLogic-CompatibleSHDNInput Ordering Information appears at end of data sheet. For related parts and recommended products to use with this part, refer to www.maxim-ic.com/MAX98309.related. Applications Cell Phones/Smartphones Digital Cameras GPS Portable Media Players e-Readers Tablets Simplified Block Diagram RF 2.5V TO 5.5V 0.1µF 2.5V TO 5.5V 1µF 0.1µF 1µF BIAS BIAS VDD GAIN BIAS BIAS CIN RIN INBIAS IN+ SHDN GND VDD TON RF VDD INRIN MAX98310 MAX98309 OUT+ CIN OUT+ BIAS OUTGND RF CIN RIN OUT- CIN IN+ RIN RF SHDN GND  ���������������������������������������������������������������� Maxim Integrated Products  1 � Forpricing,delivery,andorderinginformation,pleasecontactMaximDirectat1-888-629-4642, orvisitMaxim’swebsiteatwww.maxim-ic.com. MAX98309/MAX98310 Mono 1.4W Class AB Audio Amplifiers ABSOLUTEMAXIMUMRATINGS VDD to GND............................................................... -0.3V to 6V SHDN to GND ........................................................... -0.3V to 6V All Other Pins to GND ...............................-0.3V to (VDD + 0.3V) Continuous Current VDD, GND, OUT_....................................................... Q750mA IN_, SHDN, BIAS, GAIN, TON......................................... Q20mA OUT_ Short Circuit to GND or VDD Duration ............ Continuous OUT+ to OUT- Short Circuit Duration ....................... Continuous Continuous Power Dissipation (TA = +70NC) WLP (derate 11.9mW/NC above +70NC)...................... 848mW 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. PACKAGETHERMALCHARACTERISTICS (Note1) WLP Junction-to-Ambient Thermal Resistance (BJA)......... 94°C/W Junction-to-Case Thermal Resistance (BJC) ............... 41°C/W Note1: 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. ELECTRICALCHARACTERISTICS (VDD = 3.7V, VGND = 0V, SHDN = VDD, GAIN = VDD (0dB), CBIAS = 0.1µF, CIN = 0.47µF, no load: RIN = RF = 10kI (MAX98309), TA = TMIN to TMAX. Typical values are at TA = +25°C, unless otherwise noted.) (Note 2) PARAMETER Supply Voltage Range Undervoltage Lockout Quiescent Supply Current Shutdown Supply Current SYMBOL VDD UVLO IVDD IVDD_SD tON VDD falling SHDN = VDD VDD = 3.7V VDD = 5V CONDITIONS Guaranteed by PSRR test MIN 2.5 1.8 1.2 1.9 2 10 100 5.7 -0.25 2.75 5.75 8.75 0.80 x VDD 0.05 x VDD 0.16 x VDD 0.35 x VDD 0.24 x VDD 0.69 x VDD 0 3 6 9 11.5 +0.25 3.25 6.25 9.25 dB 1.8 3 22.8 ms TYP MAX 5.5 2.3 UNITS V V mA FA Turn-On Time VSHDN = 0V, TA = +25NC MAX98309 shutdown to TON = GND full operation TON = VDD MAX98310 shutdown to full operation GAIN = VDD GAIN = GND Gain AV MAX98310 GAIN = unconnected GAIN = BIAS GAIN = VDD GAIN = GND Gain Selection Threshold MAX98310 GAIN = unconnected GAIN = BIAS V  ���������������������������������������������������������������� Maxim Integrated Products  2 � MAX98309/MAX98310 Mono 1.4W Class AB Audio Amplifiers ELECTRICALCHARACTERISTICS(continued) (VDD = 3.7V, VGND = 0V, SHDN = VDD, GAIN = VDD (0dB), CBIAS = 0.1µF, CIN = 0.47µF, no load: RIN = RF = 10kI (MAX98309), TA = TMIN to TMAX. Typical values are at TA = +25°C, unless otherwise noted.) (Note 2) PARAMETER SYMBOL CONDITIONS MAX98309, SHDN = VDD Differential Input Resistance RINDIFF GAIN = 0dB MAX98310 GAIN = 3dB GAIN = 6dB Input Bias Current Shutdown Input Bias Current Output Offset Voltage IINBIAS IINBIAS_ SHDN MIN TYP 1000 38.2 31.7 25.5 MAX UNITS kI MAX98309/MAX98310, SHDN = VDD SHDN = GND, IN_ = VDD or IN_ = GND TA = +25NC (Note 3) RL = 8I, 32 samples per second, A-weighted, TA = +25NC (Notes 3, 4) Into shutdown Out of shutdown 0.475 x VDD 0.5 Guaranteed over input commonmode voltage range fIN = 1kHz, RL = 8I + 33FH DC 2.5V to 5.5V 73 fIN = 217Hz fIN = 1kHz fIN = 10kHz RL = 8I + 68FH RL = 4I + 33FH RL = 8I + 68FH RL = 4I + 33FH RL = 8I + 68FH RL = 4I + 33FH, thermally limited RL = 8I + 68FH RL = 4I + 33FH, thermally limited -5 Q0.2 -66 Q1 +5 Q1 FA FA mV VOS Click-and-Pop Level KCP dBV -66 0.5 x VDD 0.525 x VDD VDD 0.6 Common-Mode Bias Voltage Input Common-Mode Voltage Range VBIAS VCM Voltage at BIAS V Inferred from CMRR test V -50 -76 dB -62 93 90 90 72 0.750 1.2 0.9 1.5 1.4 2.1 1.7 2.7 W dB Common-Mode Rejection Ratio CMRR MAX98310/MAX98310 Power-Supply Rejection Ratio PSRR VRIPPLE = 200mVP-P (Note 3) VDD = 3.7V, 1% THD+N VDD = 3.7V, 10% THD+N Output Power POUT VDD = 5V, 1% THD+N (Note 5) VDD = 5V, 10% THD+N (Note 5)  ���������������������������������������������������������������� Maxim Integrated Products  3 � MAX98309/MAX98310 Mono 1.4W Class AB Audio Amplifiers ELECTRICALCHARACTERISTICS(continued) (VDD = 3.7V, VGND = 0V, SHDN = VDD, GAIN = VDD (0dB), CBIAS = 0.1µF, CIN = 0.47µF, no load: RIN = RF = 10kI (MAX98309), TA = TMIN to TMAX. Typical values are at TA = +25°C, unless otherwise noted.) (Note 2) PARAMETER SYMBOL CONDITIONS fIN = 1kHz, BW = 22Hz to 22kHz fIN = 6kHz, BW = 22Hz to 22kHz Signal-to-Noise Ratio Output Noise Voltage Overcurrent Protection Threshold Thermal-Protection Threshold Thermal-Protection Hysteresis Maximum Capacitive Load Drive CL Bridge-tied load capacitance SNR VN RL = 8I + 68FH, POUT = 375mW RL = 4I + 33FH, POUT = 750mW RL = 8I + 68FH, POUT = 375mW 0.06 MIN TYP 0.008 0.02 0.01 110 9 2 +160 15 500 dB FV A NC NC pF % MAX UNITS Total Harmonic Distortion Plus Noise THD+N A-weighted, VDD = 5V, POUT = 1.4W, RL = 8I + 33FH A-weighted (Note 3) LOGICINPUT(SHDN,TON)(MAX98309) Input Logic-High VIH 1.8V logic compliant Input Logic-Low Input Leakage Current High Input Leakage Current Low Note2: Note3: Note4: Note5: VIL IIH IIL 1.8V logic compliant TA = +25NC TA = +25NC 1.4 0.4 1 1 V V FA FA All specifications are 100% tested at TA = +25°C; temperature limits are guaranteed by design. Inputs AC-coupled to GND. Mode transitions controlled by SHDN. Thermally limited by package.  ���������������������������������������������������������������� Maxim Integrated Products  4 � MAX98309/MAX98310 Mono 1.4W Class AB Audio Amplifiers Typical Operating Characteristics (VDD = 3.7V, VGND = 0V, SHDN = VDD, GAIN = GND (RF = RIN = 10kI), CBIAS = 0.1µF, CIN = 1µF, no load, unless otherwise noted.) TOTAL HARMONIC DISTORTION PLUS NOISE vs. FREQUENCY MAX98309 toc01 TOTAL HARMONIC DISTORTION PLUS NOISE vs. FREQUENCY MAX98309 toc02 TOTAL HARMONIC DISTORTION PLUS NOISE vs. FREQUENCY VDD = 3.7V RL = 4I MAX98309 toc03 10 VDD = 4.2V RL = 4I 1 THD+N (%) POUT = 300mW 0.1 100 10 THD+N (%) 1 POUT = 1.2W 0.1 0.01 0.001 POUT = 200mW VDD = 5V RL = 8I 100 10 THD+N (%) 1 0.1 0.01 POUT = 50mW 0.001 POUT = 800mW 0.01 POUT = 50mW 0.001 10 100 1k FREQUENCY (kHz) 10k 100k 10 100 1k FREQUENCY (Hz) 10k 100k 10 100 1k FREQUENCY (Hz) 10k 100k TOTAL HARMONIC DISTORTION PLUS NOISE vs. FREQUENCY MAX98309 toc04 TOTAL HARMONIC DISTORTION PLUS NOISE vs. OUTPUT POWER MAX98309 toc05 TOTAL HARMONIC DISTORTION PLUS NOISE vs. OUTPUT POWER VDD = 5V RL = 8I MAX98309 toc06 100 10 THD+N (%) 100 10 THD+N (%) 1 0.1 0.01 fIN = 1kHz 0.001 fIN = 300Hz VDD = 4.2V RL = 4I 100 10 THD+N (%) 1 0.1 0.01 0.001 fIN = 1kHz 0 250 500 750 fIN = 300Hz fIN = 6kHz VDD = 3.7V RL = 8I 1 0.1 0.01 fIN = 6kHz POUT = 50mW POUT = 500mW 0.001 10 100 1k FREQUENCY (Hz) 10k 100k 0 500 1000 1500 2000 1000 1250 1500 1750 OUTPUT POWER (mW) OUTPUT POWER (mW) TOTAL HARMONIC DISTORTION PLUS NOISE vs. OUTPUT POWER MAX98309 toc07 TOTAL HARMONIC DISTORTION PLUS NOISE vs. OUTPUT POWER VDD = 3.7V RL = 8I MAX98309 toc08 100 10 THD+N (%) 1 0.1 0.01 0.001 0 fIN = 1kHz 400 800 1200 fIN = 300Hz VDD = 3.7V RL = 4I 100 10 THD+N (%) 1 0.1 0.01 fIN = 1kHz 0.001 fIN = 6kHz fIN = 300Hz fIN = 6kHz 1600 0 200 400 600 800 1000 OUTPUT POWER (mW) OUTPUT POWER (mW) ����������������������������������������������������������������� Maxim Integrated Products  5 MAX98309/MAX98310 Mono 1.4W Class AB Audio Amplifiers Typical Operating Characteristics (continued) (VDD = 3.7V, VGND = 0V, SHDN = VDD, GAIN = GND (RF = RIN = 10kI), CBIAS = 0.1µF, CIN = 1µF, no load, unless otherwise noted.) OFFSET VOLTAGE vs. COMMON-MODE VOLTAGE MAX98309 toc09 OFFSET VOLTAGE vs. COMMON-MODE VOLTAGE 3 2 VOS (mV) 1 0 -1 -2 -3 -4 VDD = 3.7V RL = 8I MAX98309 toc10 5 4 3 2 VOS (mV) 1 0 -1 -2 -3 -4 -5 0 1 2 3 4 VDD = 5V RL = 8I 4 5 0 0.5 COMMON-MODE VOLTAGE (V) 1.0 1.5 2.0 2.5 3.0 COMMON-MODE VOLTAGE (V) 3.5 OUTPUT POWER vs. SUPPLY VOLTAGE MAX98309 toc11 OUTPUT POWER vs. SUPPLY VOLTAGE 3000 OUTPUT POWER (mW) 2500 2000 1500 1000 500 0 THD+N = 1% THD+N = 10% THERMALLY LIMITED fIN = 1kHz RL = 4I MAX98309 toc12 2500 2000 OUTPUT POWER (mW) fIN = 1kHz RL = 8I THD+N = 10% 3500 1500 1000 500 0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 SUPPLY VOLATGE (V) THD+N = 10% 2.5 3.0 3.5 4.0 4.5 5.0 5.5 SUPPLY VOLATGE (V) OUTPUT POWER vs. LOAD MAX98309 toc13 OUTPUT POWER vs. LOAD 1.6 1.4 OUTPUT POWER (mW) 1.2 1.0 0.8 0.6 0.4 0.2 0 THD+N = 1% THD+N = 10% VDD = 3.7V fIN = 1kHz ZLOAD = LOAD + 68µH MAX98309 toc14 3.0 2.5 OUTPUT POWER (W) 2.0 1.5 1.0 0.5 0 1 10 VDD = 5V fIN = 1kHz ZLOAD = LOAD + 68µH THERMALLY LIMITED THD+N = 10% THD+N = 1% 1.8 100 1k 1 10 100 1k LOAD RESISTANCE (I) LOAD RESISTANCE (I) ����������������������������������������������������������������� Maxim Integrated Products  6 MAX98309/MAX98310 Mono 1.4W Class AB Audio Amplifiers Typical Operating Characteristics (continued) (VDD = 3.7V, VGND = 0V, SHDN = VDD, GAIN = GND (RF = RIN = 10kI), CBIAS = 0.1µF, CIN = 1µF, no load, unless otherwise noted.) POWER DISSIPATION vs. OUTPUT POWER MAX98309 toc15 POWER DISSIPATION vs. OUTPUT POWER MAX98309 toc16 GAIN vs. FREQUENCY (MAX98310) 12 11 10 9 8 7 6 5 4 3 2 1 0 -1 -2 -3 -4 -5 AV = 9dB AV = 6dB AV = 3dB AV = 0dB MAX98309 toc17 1400 1200 POWER DISSIPATION (mW) 1000 800 600 400 200 0 0 500 RL = 4I POWER DISSIPATION (mW) VDD = 5V fIN = 1kHz POUT = POUTL + POUTR 800 700 600 500 400 300 200 100 0 RL = 8I VDD = 3.7V fIN = 1kHz POUT = POUTL + POUTR 900 1200 RL = 4I GAIN (dB) RL = 8I 1000 1500 2000 0 300 600 1500 10 100 1k 10k 100k 1000k OUTPUT POWER (mW) OUTPUT POWER (mW) FREQUENCY (Hz) PSRR vs. FREQUENCY (MAX98309) 0 -10 -20 -30 -40 -50 -60 -70 -80 -90 -100 -110 -120 -130 -140 10 MAX98309 toc18 PSRR vs. FREQUENCY (MAX98310) RL = 8I VRIPPLE = 200mV MAX98309 toc19 RL = 8I VRIPPLE = 200mV 0 -10 -20 -30 PSRR (dB) -40 -50 -60 -70 -80 -90 -100 -110 -120 PSRR (dB) VDD = 5V VDD = 3.7V VDD = 3.7V VDD = 5V 10 100 1k FREQUENCY (Hz) 10k 100k 100 1k FREQUENCY (Hz) 10k 100k CMRR vs. FREQUENCY (MAX98309) MAX98309 toc20 CMRR vs. FREQUENCY (MAX98310) -10 -20 -30 CMRR (dB) -40 -50 -60 -70 -80 -90 -100 VDD = 5V VDD = 3.7V RL = 8I THD + N = 1% MAX98309 toc21 0 -10 -20 -30 CMRR (dB) -40 -50 -60 -70 -80 -90 -100 10 RL = 8I THD + N = 1% 0 VDD = 3.7V VDD = 5V 100 1k FREQUENCY (Hz) 10k 100k 10 100 1k FREQUENCY (Hz) 10k 100k ����������������������������������������������������������������� Maxim Integrated Products  7 MAX98309/MAX98310 Mono 1.4W Class AB Audio Amplifiers Typical Operating Characteristics (continued) (VDD = 3.7V, VGND = 0V, SHDN = VDD, GAIN = GND (RF = RIN = 10kI), CBIAS = 0.1µF, CIN = 1µF, no load, unless otherwise noted.) TURN-ON TIME (MAX98309) 10ms MAX98309 toc22 TURN-ON TIME (MAX98309) 100ms MAX98309 toc23 TURN-ON TIME MAX98310 MAX98309 toc24 2ms/div 20ms/div 1ms/div SUPPLY CURRENT vs. SUPPLY VOLTAGE MAX98309 toc25 SUPPLY CURRENT vs. TEMPERATURE VDD = 5V 2.0 SUPPLY CURRENT (mA) 1.5 1.0 0.5 0 MAX98309 toc26 3.0 2.5 SUPPLY CURRENT (mA) 2.0 1.5 1.0 0.5 0 2.5 3.0 3.5 4.0 4.5 5.0 2.5 VDD = 3.7V 5.5 -40 -15 10 35 60 85 SUPPLY VOLTAGE (V) TEMPERATURE (°C) SHUTDOWN CURRENT vs. SUPPLY VOLTAGE MAX98309 toc27 SHUTDOWN CURRENT vs. TEMPERATURE 9 SHUTDOWN CURRENT (µA) 8 7 6 5 4 3 2 1 0 VDD = 3.7V VDD = 5V MAX98309 toc28 9 8 SHUTDOWN CURRENT (µA) 7 6 5 4 3 2 1 0 2.5 3.0 3.5 4.0 4.5 5.0 10 5.5 -40 -15 10 35 60 85 SUPPLY VOLTAGE (V) TEMPERATURE (°C) ����������������������������������������������������������������� Maxim Integrated Products  8 MAX98309/MAX98310 Mono 1.4W Class AB Audio Amplifiers Pin Configurations TOP VIEW (BUMP SIDE DOWN) 1 MAX98309 2 SHDN 3 TOP VIEW (BUMP SIDE DOWN) 1 MAX98310 2 SHDN 3 IN- + A OUT+ INA + OUT+ B GND TON VDD B GND GAIN VDD C OUT- BIAS IN+ C OUT- BIAS IN+ WLP WLP Pin Descriptions PIN MAX98309 A1 A2 A3 B1 B2 — B3 C1 C2 C3 MAX98310 A1 A2 A3 B1 — B2 B3 C1 C2 C3 NAME OUT+ SHDN INGND TON GAIN VDD OUTBIAS IN+ Amplifier Positive Output Active-Low Shutdown Input. Connect to GND to place the IC into shutdown. Connect to VDD for normal operation. Inverting Audio Input Ground Turn-On Time Selection. Connect TON to GND for a 10ms turn-on time. Connect TON to VDD for a 100ms turn on time. Gain Select Input. See Table 1 for gain settings. Power Supply Input. Connect a 1FF capacitor from VDD to GND. Amplifier Negative Output Common-Mode DC Bias Bypass. Connect a 0.1FF (min) capacitor to GND. Noninverting Audio Input FUNCTION  ���������������������������������������������������������������� Maxim Integrated Products  9 � MAX98309/MAX98310 Mono 1.4W Class AB Audio Amplifiers Detailed Description The MAX98309/MAX98310 mono 1.4W Class AB audio amplifiers offer low quiescent current while maintaining excellent SNR and low 0.008% THD+N. Both ICs feature excellent 90dB PSRR and state-of-the-art click-and-pop suppression. The ICs are offered with an internally fixed 0dB, 3dB, 6dB, and 9dB gain (MAX98310) or an externally set gain (MAX98309) through external resistors. The MAX98309 features a 10ms or 100ms pin-selectable turn-on time, while the MAX98310 has a preset 5ms turnon time. The ICs operate from a single 2.5V to 5.5V power supply and feature an internally generated common-mode bias voltage of VDD/2 reference to ground. BIAS provides both click-and-pop suppression and sets the DC bias level for the audio outputs. Choose the value of the bypass capacitor as described in the BIAS Capacitor section. Do not connect external loads to BIAS as this can affect the overall performance. The MAX98309 external gain amplifier features a selectable turn-on time for optimized click-and-pop performance. Connect TON to GND for a 10ms turn-on time. Connect TON to VDD for a 100ms turn-on time. The MAX98310 has a preset 5ms turn-on time. The ICs feature a 1.8FA low-power shutdown mode that reduces quiescent current consumption. When the active-low shutdown mode is entered, the ICs’ internal bias circuitry is disabled, the amplifier outputs go high impedance, and BIAS is driven to GND. The ICs feature Maxim’s industry-leading click-andpop suppression circuitry. During startup, the amplifier common-mode bias voltage ramps to the DC bias point. When entering shutdown, the amplifier outputs are high impedance between both outputs. This scheme minimizes the energy present in the audio band. Applications Information The ICs are designed to drive a load differentially, a configuration referred to as bridge-tied load, or BTL. The BTL configuration (Figure 1) offers advantages over the single-ended configuration, where one side of the load is connected to ground. Driving the load differentially doubles the output voltage compared to a single-ended amplifier under similar conditions. Substituting 2 x VOUT(P-P) for VOUT(P-P) into the following equations yields four times the output power due to doubling of the output voltage: 22 VRMS 2 POUT = RL Because the differential outputs are biased at midsupply, there is no net DC voltage across the load. This eliminates the need for DC-blocking capacitors required for single-ended amplifiers. These capacitors can be large, expensive, consume board space, and degrade lowfrequency performance. Under normal operating conditions, the ICs dissipate a significant amount of power. The maximum power dissipation is given in the Absolute Maximum Ratings or can be calculated by the following equation: PD(MAX) = TJ(MAX) − TA θ JA VRMS = VOUT (P −P) BTL Amplifier Bias Turn-On Time Power Dissipation and Heatsinking Shutdown Mode Click-and-Pop Suppression where TJ(MAX) is +150NC, TA is the ambient temperature, and BJA is the reciprocal of the derating factor in C/W as specified in the Absolute Maximum Ratings. +1 VOUT(P-P) 2 x VOUT(P-P) -1 VOUT(P-P) Figure 1. BTL Configuration  ��������������������������������������������������������������� Maxim Integrated Products  10 � MAX98309/MAX98310 Mono 1.4W Class AB Audio Amplifiers The increase in power delivered by the BTL configuration directly results in an increase in internal power dissipation over the single-ended configuration. The maximum internal power dissipation for a given VDD and load is given by the following equation: π 2R L If the internal power dissipation for a given application exceeds the maximum allowed for a given package, reduce power dissipation by increasing the ground plane heatsinking capability and the size of the traces to the device. See the Layout and Grounding section. Other methods for reducing power dissipation are to reduce VDD, increase load impedance, decrease ambient temperature, reduce gain, or reduce input signal. Thermal-overload protection limits total power dissipation in the MAX98309/MAX98310. When the junction temperature exceeds +160NC, the thermal protection circuitry disables the amplifier. Operation returns to normal once the die cools by 15NC. PD(MAX) = 2VDD 2 The fully differential amplifier inputs can be biased at voltages other than midsupply. The common-mode feedback circuit adjusts for input bias, ensuring the outputs are still biased at midsupply. Input capacitors are not required as long as the input voltage is within the specified common-mode range listed in the Electrical Characteristics table. Input Filter If input capacitors are used, input capacitor CIN, in conjunction with the input resistor RIN, forms a highpass filter that removes the DC bias from an incoming signal. The AC-coupling capacitor allows the amplifier to bias the signal to an optimum DC level. Assuming zero-source impedance, the -3dB point of the highpass filter is given by: f−3dB = 1 2πRIN CIN Amplifier Gain Fixed Differential Gain (MAX98310) The MAX98310 features four internally fixed differential gain options selectable by GAIN (Table 1). This simplifies design, decreases required application footprint size, and eliminates external gain-setting resistors. External Differential Gain (MAX98309) The MAX98309 features an external gain option. Resistors RF and RIN. See the Simplified Block Diagram and set the gain of the amplifier as follows: AV = RF RIN Setting f-3dB too high affects the low-frequency response of the amplifier. Use capacitors with adequately low voltage coefficients, such as X7R ceramic capacitors with a high voltage rating. Capacitors with higher voltage coefficients result in increased distortion at low frequencies. BIAS is the output of the internally generated VDD/2 bias voltage. The BIAS bypass capacitor, CBIAS, improves PSRR and THD+N by reducing power supply and other noise sources at the common-mode bias node, and also generates the clickless/popless startup DC bias waveform for the speaker amplifiers. Bypass BIAS with a 0.1FF capacitor to GND. Larger values of CBIAS (up to 1FF) improve PSRR. Proper power-supply bypassing ensures low-noise, lowdistortion performance. Connect a 1FF ceramic capacitor from VDD to GND. Add additional bulk capacitance as required by the application. Locate the bypass capacitor as close as possible to the device. Good PCB layout is essential for optimizing performance. Use large traces for the power-supply inputs and amplifier outputs to minimize losses due to parasitic trace resistance and route heat away from the device. Good grounding improves audio performance, and prevents any digital switching noise from coupling into the audio signal. BIAS Capacitor Supply Bypassing where AV is the desired voltage gain. Hence, an RIN of 10kI and an RF of 20kI yields a gain of 2V/V or 6dB. RF can be either fixed or variable, allowing the use of a digitally controlled potentiometer to alter the gain under software control. Layout and Grounding Table1.FixedDifferentialGain GAINCONNECTION VDD GND Unconnected BIAS GAIN(dB) 0 3 6 9  ��������������������������������������������������������������� Maxim Integrated Products  11 � MAX98309/MAX98310 Mono 1.4W Class AB Audio Amplifiers Ordering Information PART MAX98309EWL+ MAX98310EWL+ TEMPRANGE -40NC to +85NC -40NC to +85NC GAIN External Fixed PIN-PACKAGE 9 WLP 9 WLP TOPMARK +AIY +AIZ +Denotes a lead(Pb)-free/RoHS-compliant package.  ��������������������������������������������������������������� Maxim Integrated Products  12 � MAX98309/MAX98310 Mono 1.4W Class AB Audio Amplifiers 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. PACKAGETYPE 9 WLP (0.3mm pitch) PACKAGECODE W91D1+1 OUTLINENO. 21-0486 LANDPATTERNNO. Refer to ApplicationNote1891 COMMON DIMENSIONS A 0.64 0.16 0.05 0.03 PIN 1 INDICATOR 1 A E MARKING A1 A3 A1 A2 A3 0.48 REF 0.025 BASIC 0.21 0.03 A2 A b D1 AAAA D 0.05 S S See Note 7 SIDE VIEW 0.60 BASIC 0.60 BASIC 0.30 0.00 0.00 BASIC BASIC BASIC E1 e SD SE TOP VIEW E PKG. CODE W91D1+1 E1 e SE SD MIN MAX MIN D MAX DEPOPULATED BUMPS 0.95 0.98 0.95 0.98 NONE B C B A 1 2 3 D1 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 PACKAGE OUTLINE 9 BUMPS, WLP PKG. 0.3mm PITCH DOCUMENT CONTROL NO. -DRAWING NOT TO SCALE- APPROVAL 21-0486 REV. B 1 1  ��������������������������������������������������������������� Maxim Integrated Products  13 � MAX98309/MAX98310 Mono 1.4W Class AB Audio Amplifiers Revision History REVISION NUMBER 0 REVISION DATE 6/11 Initial release DESCRIPTION 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 © 14 2011 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc.