LM49250 - Enhanced Emissions Suppression Stereo Class D Audio Sub-System with Ground Referenced Headphone Amplifier from the PowerWise® Family
Datasheet Packaging Samples & Pricing Knowledge Base

Features
Output Short Circuit Protection
Thermal Overload Protection
Stereo filterless Class D operation
Spread spectrum modulation
Ground referenced Headphone Drivers
I 2C Control Interface
32-step input volume control
Output volume control
Minimum external components
Click and Pop suppression
Micro-power shutdown
Available in space-saving 36–bump µSMD package
Single supply operation
RF suppression

Key Specification


Power Output at VDD = 5V  
 Speaker:   RL = 4Ω, THD+N 1%   RL = 4Ω, THD+N 10%   RL = 8Ω, THD+N 1% 1.97W/Ch 2.4W/Ch 1.2W/Ch
 Headphone:   RL = 16Ω, THD+N 1%   RL = 32Ω, THD+N 1% 41mW/Ch 45mW/Ch
 Earpiece:   RL = 16Ω, THD+N 1%   RL = 32Ω, THD+N 1% 170mW 90mW
Shutdown Current 0.1μA
Efficiency at 5V, 1W into 8Ω 87%
Efficiency at 3.6V, 500mW into 8Ω 85%

General Description


The LM49250 is a fully integrated audio subsystem designed for stereo cell phone applications. More...


Applications


Mobile phones
Portable Navigation Devices
Portable Media Players
  Typical Application
click for larger image


ParametersValues
Power@ 4Ohms, 10% THD 1.210 Watt
Power@ 4Ohms, 1% THD 0.985 Watt
Power@ 8Ohms, 10% THD 0.775 Watt
Power@ 8Ohms, 1% THD 0.625 Watt
THD 0.02 %
PSRR 95 dB
SNR Undefined dB
Channels 3 Channels
THD Conditions LS mode 2, RL=8ohms, Pout=300mW
PSRR Conditions HP mode 2, f=217Hz, Vripple=200mVpp
SNR Conditions Undefined
User Supply 3.6 Volt
Audio Mux Yes
Capless Headphone Yes
ClassD Driver Yes
Interface I2C
Stereo Inputs 2
National 3D Yes
Digital Volume Control Max 21 dB
Digital Volume Control Min -64 dB
Output Modes 100
Supply Range +2.7 - +5.5 V
Mono Inputs Differential
Temperature Min -40 deg C
Temperature Max 85 deg C
Loudspeaker Type Class D
Headphone Type True Ground
Loudspeaker Outputs 3
PowerWise Yes


Typical Performance


click for larger image


  Connection Diagram
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Datasheet
RoHS Compliance Information Size in KbytesDate Click link below to Download
LM49250  Enhanced Emissions Suppression Stereo Class D Audio Sub-System with Ground Referenced Headphone Amplifier and Mono Earpiece 1350
Kbytes
15-Dec-08 Download

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Package Availability, Models, Samples & Pricing
Part NumberPackageFactory Lead TimeModelsSamples &
Electronic
Orders
Budgetary PricingStd
Pack
Size
Package
Marking
Format
TypePinsSpec.MSL
Rating
Peak
Reflow
RoHS
Report
CAD
Symbols
WeeksQtyQty$US each
LM49250RLMICRO SMDXT36NOPB1260RoHS N/A Full productionN/A
Samples
Buy Now
1K+$2.40reel
of
250
XYTT
I GJ1
6 weeksN/A
LM49250RLXMICRO SMDXT36NOPB1260RoHS N/A Full productionN/A
 
Buy Now
1K+$2.40reel
of
1000
XYTT
I GJ1
6 weeksN/A

General Description


The LM49250 is a fully integrated audio subsystem designed for stereo cell phone applications. The LM49250 combines a 2.4W/Ch stereo class D speaker amplifiers with a 45mW/Ch stereo ground referenced headphone amplifier, a class AB earpiece amplifier, National 3D enhancement, volume control, and an input mixer into a single device. The filterless class D amplifiers deliver 1.2W/Ch into an 8Ω load with <1% THD+N from a 5V supply.

The LM49250 features a new circuit technology that utilizes a charge pump to generate a negative supply voltage. This allows the headphone outputs to be biased about ground, thereby eliminating the output-coupling capacitors.

For improved noise immunity, the LM49250 features fully differential left, right and mono inputs. The three inputs can be mixed/multiplexed to any output combination of the loudspeaker, headphone or earpiece amplifiers. The left and right differential inputs can be used as separate single-ended inputs, mixing multiple stereo audio sources. The mixer, volume control, and device mode select are controlled through an I 2C compatible interface.

Output short circuit and thermal overload protection prevent the device from being damaged during fault conditions. Superior click and pop suppression eliminates audible transients on power-up/down and during shutdown.

[Information as of 7-Nov-2009]