max9744 Maxim Integrated Products, Inc., max9744 Datasheet

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... The MAX9744 features a 64-step dual-mode (analog or digital), programmable volume control and mute func- tion. The MAX9744 operates from a 4.5V to 14V single supply and can deliver up to 20W per channel into a 4Ω speaker with a 14V supply. The MAX9744 offers two modulation schemes: a fixed- ...

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Stereo Class D Speaker Amplifier with Volume Control ABSOLUTE MAXIMUM RATINGS PVDD to PGND ....................................................................+16V V to GND ...........................................................................+4V DD FB_, SYNCOUT, SYNC, SDA/VOL, ADDR1, ADDR2 to GND........................................-0. BOOT_ to V ..........................................................-0.3V to +6V DD BOOT_ to ...

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Stereo Class D Speaker Amplifier ELECTRICAL CHARACTERISTICS (continued) (PVDD = 12V 3.3V, GND = PGND = 0V OUT_+ and OUT_ ∞, unless otherwise stated spectrum mode, filterless modulation mode, see the ...

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Stereo Class D Speaker Amplifier with Volume Control ELECTRICAL CHARACTERISTICS (continued) (PVDD = 12V 3.3V, GND = PGND = 0V OUT_+ and OUT_ ∞, unless otherwise stated spectrum mode, filterless modulation ...

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... Note 1: All devices are 100% production tested at +25°C. All temperature limits are guaranteed by design. Note 2: See the Gain-Setting Resistors section. Note 3: Measured on the MAX9744 Evaluation Kit. Note 4: Testing performed with an 8Ω resistive load connected across BTL output. Mode transitions are controlled by SHDN or MUTE pin, respectively ...

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Stereo Class D Speaker Amplifier with Volume Control (V = 12V 3.3V PVDD DD GND PGND OUT_+ and OUT_- with an inductor in series, 8Ω load 68µH, 4Ω load, L= 33µH. R ...

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Stereo Class D Speaker Amplifier (V = 12V 3.3V PVDD DD GND PGND OUT_+ and OUT_- with an inductor in series, 8Ω load 68µH, 4Ω load, L= 33µ 0.47µF, ...

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... THD+N = 10% 95 THD 1kHz 8Ω L FILTERLESS MODULATION SUPPLY VOLTAGE (V) OUTPUT POWER vs. SUPPLY VOLTAGE f = 1kHz 4Ω L PWM MODE THD+N = 10% THD SUPPLY VOLTAGE (V) = 2.2µF, MAX9744 toc19 5W = 1kHz IN = 8Ω ...

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Stereo Class D Speaker Amplifier (V = 12V 3.3V PVDD DD GND PGND OUT_+ and OUT_- with an inductor in series, 8Ω load 68µH, 4Ω load, L= 33µ 0.47µF, ...

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... FREQUENCY (MHz) 10 ______________________________________________________________________________________ Typical Operating Characteristics (continued 0V; max volume setting; all speaker load resistors connected between MUTE = +25°C, unless otherwise noted.) A OUTPUT WAVEFORM (PWM) MAX9744 toc34 2V/div 2V/div 1μs/div WIDEBAND OUTPUT SPECTRUM (FIXED-FREQUENCY MODULATION MODE) 20 RBW = 1kHz INPUT AC GROUNDED 0 ...

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... LEFT TO RIGHT -60 -70 -80 -90 -100 -60 -50 -40 -30 -20 - AMPLITUDE (dBV) 2.5 3.0 3 3.8 4.0 = ∞, unless otherwise stated BIAS TURN-ON/OFF RESPONSE MAX9744 toc43 20 100ms/div SUPPLY CURRENT (PVDD) vs. SUPPLY VOLTAGE PWM MODE FILTERLESS MODULATION SUPPLY VOLTAGE (V) SHUTDOWN CURRENT vs ...

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Stereo Class D Speaker Amplifier with Volume Control PIN NAME Left-Channel Positive Speaker Output Boost Flying-Capacitor Connection. Connect a 0.1µF 1 BOOTL+ ceramic capacitor between BOOTL+ and OUTL OUTL+ Left-Channel Speaker Output, Positive Phase 4, 5, 29, ...

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... EP heat conduction path from the die to the PCB. Connect the exposed thermal pad to PGND. Detailed Description The MAX9744 20W filterless, stereo Class D audio power amplifier offers Class AB performance with Class D efficiency with a minimal board space solution. The MAX9744 features a spread-spectrum modulation scheme offering significant improvements to switch- mode amplifier technology ...

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... LC filter required by traditional Class D amplifiers, reducing component count and con- serving board space and system cost. Although the MAX9744 meets FCC and other EMI limits with a low- cost ferrite bead filter, many applications still may want to use a full LC-filtered output. If using a full LC filter, audio performance is best with the MAX9744 configured for classic PWM output ...

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... When the device is muted, the outputs do not stop switching; only the volume level is muted to the speaker. Mute only affects the output stage and does not shut down the device. To mute the MAX9744, drive MUTE to logic-high. MUTE should be held high during system power-up and power-down to ensure that pops caused by circuits before the MAX9744 are eliminated ...

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... Each word transmitted over the bus is 8 bits long C mode, vol- and is always followed by an acknowledge clock pulse. The MAX9744 SDA line operates as both an input and an open-drain output. A pullup resistor, greater than 500Ω, is required on the SDA bus. The MAX9744 SCL line operates as an input only. A pullup resistor, greater than 500Ω ...

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... STOP condition occurs in the same high pulse as a START condition. The slave address of the MAX9744 is 8 bits and con- sists of 3 fields: the first field is 5 bits wide and is fixed (10010), the second bit field which is set through ADDR1 and ADDR2 (externally connected as logic-high or logic-low), and the third field is a R/W flag bit ...

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... Table 3), one byte of data to the command register, and a STOP condition. Figure 6 illustrates the proper format for one frame. A write to the MAX9744 consists of a 6-step sequence as seen below: 1) The master sends a START condition. 2) The master sends the 7 bits slave ID plus a write bit (low) ...

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Stereo Class D Speaker Amplifier Table 7. Speaker Volume Levels ...

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Stereo Class D Speaker Amplifier with Volume Control Table 7. Speaker Volume Levels (continued ...

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... MAX9744 Figure 8. Output Filter for PWM Mode ______________________________________________________________________________________ with Volume Control Some applications use the MAX9744 with a full induc- tor/capacitor-based (LC) output filter. This is common for longer speaker lead lengths and to gain increased margin to EMC limits. Select the PWM output mode and use fixed-frequency modulation mode for best audio performance ...

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... IN F The input amplifier can be configured into a variety of circuits. The FB terminal is an actual operational ampli- fier output, allowing the MAX9744 to be configured as a summing amplifier, a filter equalizer, for example. An input capacitor ( conjunction with the input IN impedance of the MAX9744 form a highpass filter that removes the DC bias from an incoming signal ...

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... High output trace resistance decreases the power delivered to the load. Large output, supply, and GND traces allow more heat to move from the MAX9744 to the air, decreasing the thermal impedance of the circuit. The MAX9744 thin QFN package features an exposed thermal pad on its underside. This pad lowers the pack- age’ ...

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... SYNC (SHOWN MODE 29.5dB 17Hz, SPREAD-SPECTRUM MODE, MUTE OFF, SLAVE ADDRESS = 1001011_) V -3dB 24 ______________________________________________________________________________________ Functional Diagrams/Typical Application Circuits MODE 10, 21, 28 MAX9744 FBL 17 INL 16 BIAS VOLUME CONTROL INR 19 FBR 18 MUTE SHUTDOWN 8 CONTROL ANALOG CONTROL 25 OSCILLATOR N.C. ...

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... Maxim reserves the right to change the circuitry and specifications without notice at any time. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 25 © 2007 Maxim Integrated Products with Volume Control ANALOG MODE 10, 21, 28 MAX9744 FBL 17 INL 16 BIAS VOLUME CONTROL INR 19 FBR 18 MUTE ...