max9738 Maxim Integrated Products, Inc., max9738 Datasheet
max9738
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max9738 Summary of contents
Page 1
... Maxim’s proprietary output stage provides efficiency levels greater than Class AB devices without the EMI penalties commonly associat- ed with Class D amplifiers. The MAX9738 is ideally suited to deliver the high output voltage swing required to drive ceramic/piezoelectric speakers. The device utilizes fully differential inputs and outputs, comprehensive click-and-pop suppression, shutdown control, and soft-start circuitry ...
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Class G Amplifier with P-P Inverting Boost Converter ABSOLUTE MAXIMUM RATINGS (Voltages with respect to GND ............................................................... -0.3V to +6V DD BAT ......................................................... -0.1V to +0.1V DD BAT V ...................................................Capacitor Connection Only, SS ...
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ELECTRICAL CHARACTERISTICS (continued) = SHDN = 3.6V, GND = 0V BAT C1 = 10μ 10μ 0.1μ 0.1μF, T PARAMETER SYMBOL SPEAKER AMPLIFIER Output Offset Voltage V Input DC Bias ...
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Class G Amplifier with P-P Inverting Boost Converter ELECTRICAL CHARACTERISTICS (continued) = SHDN = 3.6V, GND = 0V BAT C1 = 10μ 10μ 0.1μ 0.1μF, T PARAMETER SYMBOL ...
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SHDN =+3.6V, GND = 0V BAT C2 = 10μ 0.1μ 0.1μ +25°C, Typical Application Circuit .) A TOTAL HARMONIC DISTORTION PLUS NOISE vs. FREQUENCY 2.7V ...
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... SHUTDOWN WAVEFORM 10ms/div EFFICIENCY vs. V LOAD CURRENT 3. LOAD ON V INPUT AC-GROUNDED 10 NO LOAD ON AMPLIFIER 100 150 200 250 300 V LOAD CURRENT (mA 1kHz MAX9738 toc15 SHDN 5V/div OUT+ - OUT- 500mV/div ONLY SS 350 400 ...
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... BOOST CONVERTER-INDUCTOR CURRENT SCOPE PHOTO (3.6V) MAX9738 toc20 f = 10kHz IN LX 10V/div I INDUCTOR 1A/div I LOAD 500mV/div OUT+ - OUT- 10V/div 4μs/div BOOST CONVERTER-INDUCTOR CURRENT SCOPE PHOTO (4.2V) MAX9738 toc22 f = 10kHz IN LX 10V/div I INDUCTOR 1A/div I LOAD 500mV/div OUT+ - OUT- 10V/div 4μs/div FREQUENCY RESPONSE ...
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... The Class G output stage and the inverting boost con- verter allow the MAX9738 to deliver a 16V swing four times greater than a Class AB amplifier. Class G Operation The MAX9738 Class G amplifier is a linear amplifier that operates within a low (V to GND) and high ( supply range ...
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... P N1 Figure 1. Class G Supply Transition Inverting Boost Converter The MAX9738 features an integrated inverting boost converter with an on-chip n-channel MOSFET to pro- vide an inverted supply rail that can supply up to 400mA over the +2.7V to +5.5V positive supply range. The boost converter generates the negative supply rail ...
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... Above 5kHz the typical speaker impedance can be less than 20Ω. The MAX9738 is ideal for driving a capacitive ceramic speaker. The high boost converter current limit allows for a flat frequency response out to 20kHz while main- taining high output voltage swings ...
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... MOSFET driver supply. IN The MAX9738 operates with a standard 2.2μH inductor for the entire range of supply voltages and load cur- rents. The inductor must have a saturation (incremen- tal) current (I current. Choose an inductor that has a higher I ing than the given FET Current Limit (Transient) specifi- cation in the Electrical Characteristics table ...
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... C L SPEAKER Increasing the value of R decreases the amount of L high-frequency audio content sent to the speaker, but improves the MAX9738’s power dissipation. Lowering 12 ______________________________________________________________________________________ Characteristics Figure 4. Ceramic Speaker and Capacitor Impedance the value of R more power dissipation promise between power dissipation and frequency response when coupled with a typical ceramic speaker ...
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... Typical Application Circuit/Functional Diagram BAT BAT VREF ISET BOOST REGULATOR CONTROL SHDN SHUTDOWN LOGIC FB+ IN+ CLASS G OUTPUT STAGE IN- FB- MAX9738 GND C2 10μ BAT SS BST C3 0.1μ 2.2μ 20Ω OUT SPEAKER 1.6μF ...
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... Class G Amplifier with P-P Inverting Boost Converter Pin Configuration TOP VIEW (BUMP SIDE DOWN) MAX9738 SHDN BAT BAT BST OUT- GND DD 20-BUMP WLP Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied ...