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LM4941 -
1.25 Watt Fully Differential Audio Power Amplifier With RF Suppression and Shutdown from the PowerWise® Family
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Features
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Improved RF suppression, by up to 20dB over previous designs in selected applications
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Fully differential amplification
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Available in space-saving micro SMD package
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Ultra low current shutdown mode
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Can drive capacitive loads up to 100pF
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Improved pop & click circuitry eliminates noises during turn-on and turn-off transitions
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2.4 - 5.5V operation
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No output coupling capacitors, snubber networks or bootstrap capacitors required
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Key Specification
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Improved PSRR at 217Hz
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95dB (typ)
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Power Output, VDD = 5.0V,
RL = 8Ω, 1% THD+N
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1.25W (typ)
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Power Output, VDD = 3.0V,
RL = 8Ω, 1% THD+N
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430mW (typ)
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Shutdown Current
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0.1µA (typ)
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General Description
The LM4941 is a fully differential audio power amplifier primarily designed for demanding applications in mobile phones and
other portable communication device applications. More...
Applications
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Mobile phones
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PDAs
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Portable electronic devices
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Typical Application
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Parametric Table
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Parametric Table
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Typical Performance
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Additional Resources
Application Notes (see below)
Connection Diagram
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Datasheet
Package Availability, Models, Samples & Pricing
General Description
The LM4941 is a fully differential audio power amplifier primarily designed for demanding applications in mobile phones and
other portable communication device applications. It is capable of delivering 1.25 watts of continuous average power to a
8Ω load with less than 1% distortion (THD+N) from a 5VDC power supply. The LM4941 does not require output coupling capacitors or bootstrap capacitors, and therefore is ideally suited
for mobile phone and other small form factor applications where minimal PCB space is a primary requirement.
The LM4941 also features proprietary internal circuitry that suppresses the coupling of RF signals into the chip. This is
important because certain types of RF signals (such as GSM) can couple into audio amplifiers in such a way that part of the
signal is heard through the speaker. The RF suppression circuitry in the LM4941 makes it well-suited for portable applications
in which strong RF signals generated by an antenna from or a cellular phone or other portable electronic device may couple
audibly into the amplifier.
Other features include a low-power consumption shutdown mode, internal thermal shutdown protection, and advanced pop & click
circuitry.
Reliability Metrics
| Part Number |
Process |
EFR Reject |
EFR Sample Size |
PPM |
LTA Rejects |
LTA Device Hours |
FITS |
MTTF (Hours) |
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LM4941TM | CMOS7 | 0 | 16561 | 0 | 0 | 954000 | 4 | 270700104
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LM4941TMX | CMOS7 | 0 | 16561 | 0 | 0 | 954000 | 4 | 270700104
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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.
More Application Notes
| Title | Size in Kbytes |
Date |
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| AN-1567: Application Note 1567 LM4949 Demonstration Board |
3533 Kbytes |
18-Jul-07 |
Download |
AN-1567 (Chinese): Application Note 1567 LM4949 Demonstration Board
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1008 Kbytes |
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| AN-1496: Application Note 1496 Noise, TDMA Noise, and Suppression Techniques |
85 Kbytes |
28-Apr-08 |
Download |
AN-1496 (Chinese): Application Note 1496 Noise, TDMA Noise, and Suppression Techniques
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407 Kbytes |
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[Information as of 5-Jul-2009]
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RoHS Compliance Information
