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Numéro de sérieMAX9705
CategorieMultimedia => Audio => Amplifiers => Power Amplifiers
Description2.3W, Ultra-Low-EMI, Filterless, Class D Audio Amplifier
The MAX9705 3rd-generation, ultra-low EMI, mono, Class D audio power amplifier provides Class AB performance with Class D efficiency. The MAX9705 delivers 2.3W into a 4? load and offers efficiencies above 85%. Active emissions limiting (AEL) circuitry greatly reduces EMI by actively controlling the output FET gate transitions under all possible transient output-voltage conditions. AEL prevents high-frequency emissions resulting from conventional Class D free-wheeling behavior in the presence of an inductive load. Zero dead time (ZDT) technology maintains state-of-the-art efficiency and THD+N performance by allowing the output FETs to switch simultaneously without cross-conduction. A patented spread-spectrum modulation scheme eliminates the need for output filtering found in traditional Class D devices. These design concepts reduce an application\'s component count and extend battery life
SociétéMaxim Integrated Products
DatasheetTélécharger MAX9705 datasheet
 
 
  • Description courte

  • o Filterless Amplifier Passes FCC-Radiated Emissions Standards with 24in of Cable o Unique Spread-Spectrum Mode and Active Emissions Limiting (AEL) Achieves Better than 20dB Margin Under FCC Limits o Zero Dead Time (ZDT) H-Bridge Maintains Stateof-the-Art Efficiency and THD+N o Simple Master-Slave Setup for Stereo Operation to 90% Efficiency o 2.3W into 4 (1% THD+N) o Low 0.02% THD+N (POUT = 1W, VDD 5.0V) o High PSRR 217Hz) o Integrated Click-and-Pop Suppression o Low Quiescent Current (5.4mA) o Low-Power Shutdown Mode (0.3µA) o Short-Circuit and Thermal-Overload Protection o Available in Thermally Efficient, Space-Saving Packages 10-Pin TDFN 0.8mm) 12-Bump UCSP 0.6mm) o Pin-for-Pin Compatible with the MAX9700 and MAX9712

    The MAX9705 3rd-generation, ultra-low EMI, mono, Class D audio power amplifier provides Class AB performance with Class D efficiency. The MAX9705 delivers 2.3W into a 4 load and offers efficiencies above 85%. Active emissions limiting (AEL) circuitry greatly reduces EMI by actively controlling the output FET gate transitions under all possible transient output-voltage conditions. AEL prevents high-frequency emissions resulting from conventional Class D free-wheeling behavior in the presence of an inductive load. Zero dead time (ZDT) technology maintains state-of-the-art efficiency and THD+N performance by allowing the output FETs to switch simultaneously without cross-conduction. A patented spreadspectrum modulation scheme eliminates the need for output filtering found in traditional Class D devices. These design concepts reduce an application's component count and extend battery life. The MAX9705 offers two modulation schemes: a fixedfrequency (FFM) mode and a spread-spectrum (SSM) mode that further reduces EMI-radiated emissions due to the modulation frequency. The MAX9705 oscillator can be synchronized to an external clock through the SYNC input, allowing the switching frequency to be externally defined. The SYNC input also allows multiple to be cascaded and frequency locked, minimizing interference due to clock intermodulation. The device utilizes a fully differential architecture, a full-bridged output, and comprehensive click-and-pop suppression. The gain of the MAX9705 is set internally MAX9705D: 20dB), further reducing external component count. The MAX9705 is available in 10-pin TDFN x 0.8mm), and 12-bump UCSPTM x 0.6mm) packages. The MAX9705 is specified over the extended to +85°C temperature range.

    PART MAX9705AEBC+T MAX9705BETB+T TEMP RANGE to +85oC PINPACKAGE 10 TDFN 12 UCSP 10 TDFN TOP MARK ACY ACH ACX

    +85oC 12 UCSP ACG Ordering Information continued at end of data sheet.
    Applications
    Cellular Phones PDAs MP3 Players Portable Audio
    Selector Guide appears at end of data sheet. UCSP is a trademark of Maxim Integrated Products, Inc.

    For pricing, delivery, and ordering information, please contact Maxim Direct 1-888-629-4642, or visit Maxim's website at www.maxim-ic.com.

    VDD to GND..............................................................................6V PVDD to PGND.........................................................................6V GND to +0.3V PVDD to +0.3V All Other Pins GND.................................-0.3V to (VDD + 0.3V) Continuous Current Into/Out of PVDD/PGND/OUT_........±600mA Continuous Input Current (all other pins).........................±20mA Duration of OUT_ Short Circuit to GND or PVDD........Continuous Duration of Short Circuit Between OUT+ and OUT-.....Continuous Continuous Power Dissipation (TA +70°C) 10-Pin TDFN (derate 24.4mW/°C above +70°C).....1951.2mW 12-Bump UCSP (derate 6.1mW/°C above +70°C)........484mW Junction Temperature......................................................+150°C Operating Temperature to +85°C Storage Temperature to +150°C Lead Temperature (soldering, 10s).................................+300°C Bump Temperature (soldering) Reflow..........................................................................+235°C

    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.

    (VDD = PVDD = V SHDN = 3.3V, VGND = VPGND = 0V, SYNC = GND (FFM), , RL connected between OUT+ and OUT-, TA = TMIN to TMAX, unless otherwise noted. Typical values are = +25°C.) (Notes 1, 2)

    PARAMETER GENERAL Supply Voltage Range Quiescent Current Shutdown Current Turn-On Time Input Resistance VDD IDD ISHDN tON RIN VBIAS = +25°C Either input MAX9705C MAX9705D Inferred from PSRR test k V SYMBOL CONDITIONS MIN TYP MAX UNITS

    MAX9705A Voltage Gain MAX9705C MAX9705D Output Offset Voltage Common-Mode Rejection Ratio Power-Supply Rejection Ratio (Note 3) VOS CMRR PSRR = +25°C fIN = 1kHz, input referred VDD +25°C 200mVP-P ripple fRIPPLE = 217Hz fRIPPLE = 8 Output Power POUT THD+N = 1%, fIN 4 MAX9705_ETB+T and MAX9705_EUB+ only = 8, POUT = 4, POUT = 375mW Into shutdown Out of shutdown

    (VDD = PVDD = V SHDN = 3.3V, VGND = VPGND = 0V, SYNC = GND (FFM), , RL connected between OUT+ and OUT-, TA = TMIN to TMAX, unless otherwise noted. Typical values are = +25°C.) (Notes 1, 2)

    PARAMETER Rise/Fall Time SYMBOL tRISE, tFALL to 22kHz A-weighted SYNC = GND Oscillator Frequency fOSC SYNC = unconnected SYNC = VDD (SSM mode) SYNC Frequency Lock Range Efficiency DIGITAL INPUTS (SHDN, SYNC) Input Thresholds SHDN Input Leakage Current SYNC Input Current (Note 5) VIH VIL V µA POUT = 800mW, fIN 1kHz, RL FFM SSM FFM SSM 980 1250 CONDITIONS MIN TYP kHz dB MAX UNITS ns

    (VDD = PVDD = V SHDN = 5V, VGND = VPGND = 0V, SYNC = GND (FFM), , RL connected between OUT+ and OUT-, TA = TMIN to TMAX, unless otherwise noted. Typical values are = +25°C.) (Notes 1, 2)

    PARAMETER Quiescent Current Shutdown Current Power-Supply Rejection Ratio SYMBOL IDD ISHDN PSRR 200mVP-P ripple = 16 Output Power POUT THD+N 4 MAX9705_ETB+T and MAX9705_EUB+ only = 8, POUT = 4, POUT = 1.75W FFM SSM FFM SSM CONDITIONS MIN TYP mW dB MAX UNITS µA dB

    Note 1: All devices are 100% production tested at +25°C. All temperature limits are guaranteed by design. Note 2: Testing performed with a resistive load in series with an inductor to simulate an actual speaker load. For = 33µH. For = 68µH. For = 136µH. Note 3: Inputs AC-coupled to GND. Note 4: Testing performed with 8 resistive load in series with 68µH inductive load connected across BTL output. Mode transitions are controlled by SHDN pin. KCP level is calculated 20 x log[(peak voltage under normal operation at rated power level)/(peak voltage during mode transition, no input signal)]. Units are expressed in dB. Note 5: SYNC has a 1M resistor to VREF 1.25V. 3