max9742 Maxim Integrated Products, Inc., max9742 Datasheet
max9742
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max9742 Summary of contents
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... Class D Amplifier with Differential Inputs General Description The MAX9742 stereo Class D audio power amplifier delivers 16W into 4Ω loads. The MAX9742 features high-power efficiency (92% with 8Ω loads), eliminating the need for a bulky heatsink and conserv- ing power. The MAX9742 operates from a 20V to 40V single supply or a ± ...
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Single-/Dual-Supply, Stereo 16W, Class D Amplifier with Differential Inputs ABSOLUTE MAXIMUM RATINGS NSENSE ..............................................-0.3V to +45V DD SS MID, LGND REGM, REGP, OUTR, DD OUTL to V .......................................................-0.3V to +45V SS MID, LGND, LV ...
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Class D Amplifier with Differential Inputs ELECTRICAL CHARACTERISTICS—Single-Supply, Single-Ended Output (continued 24V LGND = 0V SUB 10kΩ 0.47µ 1000µF, C SFT OUT R = 121kΩ ...
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Single-/Dual-Supply, Stereo 16W, Class D Amplifier with Differential Inputs ELECTRICAL CHARACTERISTICS—Dual Supplies (continued 15V -15V, V SHDN DD SS SUB 150pF 10pF 0.1µF, C FB_2 BOOT 68kΩ ∞, ...
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Class D Amplifier with Differential Inputs ELECTRICAL CHARACTERISTICS—Single-Supply, BTL Configuration (V = 24V LGND = 0V SUB 10kΩ 0.47µ 1000µF, C SFT OUT = 121kΩ 562kΩ, R ...
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Single-/Dual-Supply, Stereo 16W, Class D Amplifier with Differential Inputs (24V single-supply mode, ±15V dual-supply mode, both channels driven in phase, THD+N measurement bandwidth = 22Hz to 22kHz +25°C, unless otherwise noted. See Figure 1 for test circuits, see ...
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Class D Amplifier with Differential Inputs (24V single-supply mode, ±15V dual-supply mode, both channels driven in phase, THD+N measurement bandwidth = 22Hz to 22kHz +25°C, unless otherwise noted. See Figure 1 for test circuits, see Typical Application Circuits/Functional ...
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... SYSTEM POWER 20 1.0 DUAL SUPPLY DISSIPATION R = 8Ω 0 1kHz OUTPUT POWER PER CHANNEL (W) EFFICIENCY AND POWER DISSIPATION vs. OUTPUT POWER MAX9742 toc25 EFFICIENCY 60 6 SYSTEM POWER 50 5 DISSIPATION SINGLE SUPPLY 24V 4Ω ...
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... THD+N measurement bandwidth = 22Hz to 22kHz +25°C, unless otherwise noted. See Figure 1 for test circuits, see Typical Application Circuits/Functional Diagrams for A test circuit component values.) EFFICIENCY AND POWER DISSIPATION vs. OUTPUT POWER MAX9742 toc26 100 ...
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... FREQUENCY (Hz) POWER-SUPPLY REJECTION RATIO vs. FREQUENCY 0 BTL - 24V + 500mV DD P 8Ω L -20 -30 -40 -50 -60 -70 -80 -90 -100 10 100 1k 10k 100k FREQUENCY (Hz) EXITING SHUTDOWN (DUAL SUPPLY) MAX9742 toc43 DUAL SUPPLY R = 8Ω SHDN 2V/div V OUT_ 20V/div FILTERED V OUT_ 5V/div 20ms/div 20k ...
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... SINGLE SUPPLY R = 4Ω 1.25W L OUT_ 7.8dBµV/m 35 SPEAKER CABLE BELOW LIMIT LENTH = 1m 30 5.8dBµV/m 11.3dBµV/m BELOW LIMIT BELOW LIMIT 25 7dBµV/m 20 BELOW LIMIT 15 10 3.6dBµV/m BELOW LIMIT 5 30 100 1000 FREQUENCY (MHz) MAX9742 toc46 = 8Ω MAX9742 toc49 11 ...
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Single-/Dual-Supply, Stereo 16W, Class D Amplifier with Differential Inputs PIN NAME 1, 6, 18, N.C. No Connection. Not internally connected. 27, 28 OUTL Left Speaker Output 4 SUB Device Substrate. Connect SUB BOOTL Left-Channel ...
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... The connection of external feedback components allows custom gain settings Class D amplifiers are switch-mode devices capable of significantly higher power efficiencies in comparison to linear amplifiers. The output stage of the MAX9742 con sists of a half-bridge speaker driver (see Figure 2). The high efficiency of a Class D amplifier is attributed to the AUX-0025 AUDIO region of operation of the output stage transistors ...
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... When the input signal is at 0V, the duty cycle of the MAX9742 output is equal to 50%. To extract the amplified audio signal from this PWM waveform, the output of the MAX9742 is fed to an external LC lowpass filter (see the Single-Ended LC Output Filter Design (L and C ) section). The LC filter works as an averaging F circuit for the PWM output voltage waveform ...
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... NOTE: FOR CLARITY, SIGNAL PERIODS ARE NOT SHOWN TO ACTUAL SCALE. Figure 3a. MAX9742 Output with an Applied Input Signal V OUT_ AVERAGE VALUE OF V OUT_ NOTE: FOR CLARITY, SIGNAL PERIODS ARE NOT SHOWN TO ACTUAL SCALE. Figure 3b. MAX9742 Output with Resulting Output After Filtering ______________________________________________________________________________________ Single-/Dual-Supply, Stereo 16W ...
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... When the device is muted, the outputs stop switching, muting the speaker. The mute function only affects the output stage and does not shutdown the device. To mute the MAX9742, drive SFT to ground. Figure 4 shows how an external transistor (MOSFET or BJT) can be used to easily mute the MAX9742. ...
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... IN_+ and MID whose value is equal the Feedback Capacitor (CFB_) section). Each channel of the MAX9742 can be configured as a single-ended input amplifier by connecting IN_+ to MID (through an external resistor, R the input source (see Figure 5). In this configuration, Input Amplifier ...
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... Class D Amplifier with Differential Inputs Summing Configuration (Audio Mixer) Figure 6 shows the MAX9742 configured as a summing amplifier, which allows multiple audio sources to be lin- early mixed together. Using this configuration, the out- put of the MAX9742 is equal to the weighted sum of the input signals − ...
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... BTL, only use the BTL configuration with loads greater than or equal to 8Ω. The MAX9742 may be ther- mally limited when using the BTL configuration with high supply voltages due to the decreased load resis- tance seen by each half bridge ...
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... For example, selecting a 68kΩ resistor for switching frequency of 303kHz and an output short-circuit current limit of 4.5A. To prevent damage to the MAX9742 during output short-circuit conditions and to utilize its full output power capabilities, use resistor values greater than or equal to 58kΩ and less than or equal to 75kΩ for R ...
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... The load connected to the output of F the half-bridge (LC filter and speaker) should remain inductive at the switching frequency of the MAX9742 not, a significant amount of high-frequency energy is × ζ dissipated in the resistive load, therefore, increasing ...
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... To maximize the performance of the differential output filter and minimize EMI radiation, keep the ground con- nections of the C capacitors close together on the F PCB and place the filter near the MAX9742. The component ratings for C and L F requirements mentioned in the Single-Ended LC Output Filter Design (L and C ) section ...
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... BOOT audio frequency range. Select output-coupling capacitors with DC voltage rat- ings greater than V In single-supply operation with single-ended outputs, the leakage current of C the MAX9742. To minimize startup time delays due to pre use capacitors with leakage current ratings less OUT than 1µA for C section for more information on optimizing the startup time of the MAX9742 ...
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... MID2 1µF -20 -40 -60 -80 TO -100 MID C -120 MID2 10µF Figure 12. Comparison of MAX9742 AC PSRR with Single-Pole and Two-Pole MID Networks Soft-Start Capacitor (C Startup Time Considerations is approximately equal to OUT_ ) are first gradually OUT before continuing soft-start MID POWER-SUPPLY REJECTION RATIO vs. FREQUENCY 20 SINGLE SUPPLY ...
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... For single-supply operation with single-ended outputs, the leakage current of C can also affect the startup OUT time of the MAX9742. To minimize startup time delays due use capacitors with leakage current rat- OUT ings less than 1µA for C . ...
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Single-/Dual-Supply, Stereo 16W, Class D Amplifier with Differential Inputs C VDD OFF I AVG ON C VSS CASE 1: I FLOWING INTO HALF-BRIDGE CAUSING VOLTAGE ACROSS C AVG I = AVERAGE (CONTINUOUS) OUTPUT CURRENT DURING ONE SWITCHING CYCLE. AVG I ...
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... Using large bypass capacitors helps minimize supply voltage variations by providing sufficient supply decoupling at low output frequencies. To prevent the MAX9742 from entering supply overvolt- age protection mode at low output frequencies (as low as 20Hz), use supply bypass capacitors with values of at least 1000µF for dual-supply operation and 660µF for single-supply operation ...
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... Figure 16. Connection of Output Limiting Diodes R F1a 121kΩ F1b 10pF R IN1 + R = 688kΩ F1a F1b C IN2 FB_1 150pF MAX9742 IN1 IN_ IN2 IN_ FB_1 150pF 681kΩ TO MID Output Limiting Diodes (Optional) C FB_ TO IN_- ...
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... MID to the SGND plane with a decoupling network (see Figure 11). This provides a sufficient low- and high-fre- quency AC ground for the internal amplifiers. Connect the SGND and PGND planes together at a single point in the PCB near the MAX9742. Minimize the parasitic trace inductances and resistances associated with the V and V ...
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... Place the inductor of the external LC output filter in close proximi the IC. This not only helps minimize EMI radiation at the output traces, but also helps draw heat away from the MAX9742. 30 ______________________________________________________________________________________ Pin Configuration TOP VIEW N ...
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... RIGHT NEGATIVE AUDIO INPUT DUAL SUPPLY CONFIGURATION ______________________________________________________________________________________ Single-/Dual-Supply, Stereo 16W, Simplified Block Diagram (continued FBL 10V TO 20V FBL V DD INL- MAX9742 CLASS D INL+ MODULATOR AND HALF-BRIDGE MID CLASS D MODULATOR AND INR+ HALF-BRIDGE INR- CONTROL LOGIC/ POWER-UP SEQUENCING FBR ...
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Single-/Dual-Supply, Stereo 16W, Class D Amplifier with Differential Inputs 32 ______________________________________________________________________________________ Typical Application Circuits/Functional Diagrams ...
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Single-/Dual-Supply, Stereo 16W, Class D Amplifier with Differential Inputs Typical Application Circuits/Functional Diagrams (continued) ______________________________________________________________________________________ 33 ...
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Single-/Dual-Supply, Stereo 16W, Class D Amplifier with Differential Inputs Typical Application Circuits/Functional Diagrams (continued) 34 ______________________________________________________________________________________ ...
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Class D Amplifier with Differential Inputs (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information www.maxim-ic.com/packages.) ______________________________________________________________________________________ Single-/Dual-Supply, Stereo 16W, Package Information 35 ...
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... 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. 36 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2007 Maxim Integrated Products Package Information (continued registered trademark of Maxim Integrated Products, Inc. ...