National Semiconductor | High-performance Analog

 

 LM4845   
Output Capacitor-less Audio Subsystem with Programmable National 3D 		Click link to Download

Features
  • I2C/SPI Control Interface
  • I2C/SPI programmable National 3D Audio
  • I2C/SPI controlled 32 step digital volume control (-54dB to +18dB)
  • Three independent volume channels (Left, Right, Mono)
  • Eight distinct output modes
  • microSMD surface mount packaging
  • "Click and Pop" suppression circuitry
  • Thermal shutdown protection
  • Low shutdown current (0.1uA, typ)

    • Description

    The LM4845 is an audio power amplifier capable of delivering 500mW of continuous average power into a mono 8 bridged-tied load (BTL) with 1% THD+N, 25mW per channel of continuous average power into stereo 32 single-ended (SE) loads with 1% THD+N, or an output capacitor-less (OCL) configuration with identical specification as the SE configuration, from a 3.3V power supply.

    The LM4845 features a 32-step digital volume control and eight distinct output modes. The digital volume control, 3D enhancement, and output modes (mono/SE/OCL) are programmed through a two-wire I2C or a three-wire SPI compatible interface that allows flexibility in routing and mixing audio channels. The LM4845 has three input channels: one pair for a two-channel stereo signal and the third for a single-channel mono input.

    The LM4845 is designed for cellular phone, PDA, and other portable handheld applications. It delivers high quality output power from a surface-mount package and requires only seven external components in the OCL mode (two additional components in SE mode).

    Key Specification
    THD+N at 1kHz, 500mW into 8 BTL (3.3V)1.0% (typ)
    THD+N at 1kHz, 30mW into 32 SE (3.3V)1.0% (typ)
    Single Supply Operation (VDD)2.7 to 5.5V
    I2C/SPI Single Supply Operation2.2 to 5.5V


    Applications

  • Moblie Phones
  • PDAs




    • Typical Application
    click for larger image


    		Connection Diagram
    click for larger image



    Typical Performance
    click for larger image


     

    ParametersValues
    Power @ 5V 8Ohms, 1% THD 1.15 Watt
    Speaker THD+N 0.5 %
    HP THD+N 0.5 %
    Speaker PSRR 88 dB
    HP PSRR 88 dB
    Speaker SNR Undefined dB
    Audio Mux Yes
    Audio Mode Control I2C, SPI
    Supply Range +2.7 - +5.5 V
    Temperature Min -40 deg C
    Temperature Max 85 deg C
    Mono Analog Inputs 1
    Stereo Analog Inputs 1
    Additional Audio Features National 3D
    Loudspeaker Type Class AB
    Loudspeaker Outputs 1
    Headphone Type Virtual Ground
    AEC Q-100 Automotive Grade Undefined

    Datasheets
    TitleSizeDateOther
    Language
    LM4845 Output Capacitor-less Audio Subsystem with Programmable National 3D1394
    Kbytes    		7-Jul-06   


    Application Notes
    TitleSizeDateOther
    Language
    AN-1496: Application Note 1496 Noise, TDMA Noise, and Suppression Techniques85
    Kbytes    		28-Apr-08 中文

    Part Number(s)
    (NSID)    		Top ViewAvailabilityCurrent Reported StockBudgetary PricingPack
    Size
    LM4845ITL/NOPB


    RoHS Status

    MICRO SMD    		Full production
    Lead Time: 6 weeks

    Samples
    DistributorRegionQty
    DIGI-KEYWorldwide0
    		$2.50 each at 1K+ pcsreel
    of
    250

    All information pertaining to the RoHS Compliance Standard can be found at http://www.national.com/en/packaging/leadfree.html.

    Moisture Sensitivity Level Data for LM4845.

    A RoHS compliance or an IPC 1752 report can be acquired at http://www.national.com/en/packaging/greennopb.html.

    National's certificate of product compliance for LM4845 is located at RoHS Status.

    Part Number(s)
    (NSID)    		Weight
    (milligrams)    		TypePinsMSL RatingPeak ReflowRoHS
    Status    		CAD SymbolsModelsPackage
    Marking
    Format
    LM4845ITL/NOPB

    		7.79
    		MICRO SMD251260DetailDownloadN/A
    		XYTT
    I GE5

    All information pertaining to the RoHS Compliance Standard can be found at http://www.national.com/en/packaging/leadfree.html.

    Moisture Sensitivity Level Data for LM4845.

    A RoHS compliance or an IPC 1752 report can be acquired at http://www.national.com/en/packaging/greennopb.html.

    National's certificate of product compliance for LM4845 is located at RoHS Status.

    CAD Symbols and Models
    Download LM4845 CAD Symbols
    		 Models
    N/A


    Reliability Metrics
    Part Number Process EFR Reject EFR Sample Size PPM LTA Rejects LTA Device Hours FITS MTTF (Hours)
    LM4845ITLCS065247473430552700011568301341

    Note: The Early Failure Rates (EFR) were calculated as point estimate PPM based on rejects and sample size for EFR. The Long Term Failure Rates were calculated at 60% confidence using the Arrhenius equation at 0.7eV activation energy and derating the assumed stress temperature of 150°C to an application temperature of 55°C.

    For more information on Reliability Metrics, please click here.


    All information pertaining to the RoHS Compliance Standard can be found at http://www.national.com/en/packaging/leadfree.html.

    Moisture Sensitivity Level Data for LM4845.

    A RoHS compliance or an IPC 1752 report can be acquired at http://www.national.com/en/packaging/greennopb.html.

    National's certificate of product compliance for LM4845 is located at RoHS Status.

    [Information as of 9-Feb-2012]
    Copyright © 2011 National Semiconductor Corporation