LM4915 Datasheet, PDF (1/18 Pages) National Semiconductor (TI) – Pseudo-Differential Mono Headphone Amplifier with Fixed 6dB Gain

LM4915
www.ti.com
SNAS176A – MAY 2003 – REVISED MAY 2013
LM4915
Pseudo-Differential Mono Headphone Amplifier
with Fixed 6dB Gain
Check for Samples: LM4915
FEATURES
1
•2 Pseudo-Differential Amplification
• Internal Gain-Setting Resistors
• Available in Space-Saving WQFN Package
• Ultra Low Current Shutdown Mode
• Can Drive Capacitive Loads up to 500pF
• Improved Pop & Click Circuitry Virtually
Eliminates Noises During Turn-On and Turn-
Off Transitions
• 2.2 - 5.5V Operation
• No Output Coupling Capacitors, Snubber
Networks, Bootstrap Capacitors or Gain-
Setting Resistors Required
• Ultra Low Noise
KEY SPECIFICATIONS
• Improved PSRR at 217Hz and 1kHz: 75dB (Typ)
• Power Output at 5.0V & 1% THD into 32Ω:
280mW (Typ)
• Power Output at 3.0V & 1% THD into 32Ω:
90mW (Typ)
• Output Noise, A-weighted: 20μV (Typ)
APPLICATIONS
• Mobile Phones
• PDAs
• Portable Electronics Devices
DESCRIPTION
The LM4915 is a pseudo-differential audio power
amplifier primarily designed for demanding
applications in mobile phones and other portable
audio device applications with mono headphones. It
is capable of delivering 90 miliwatts of continuous
average power to a 32Ω BTL load with less than 1%
distortion (THD+N) from a 3V_DC power supply.
Boomer audio power amplifiers were designed
specifically to provide high quality output power with a
minimal amount of external components. The
LM4915 does not require output coupling capacitors
or bootstrap capacitors, and therefore is ideally suited
for mobile phone and other low voltage applications
where minimal power consumption is a primary
requirement.
The LM4915 features a low-power consumption
shutdown mode. To facilitate this, Shutdown may be
enabled by driving the shutdown pin low. Additionally,
the LM4915 features an internal thermal shutdown
protection mechanism.
The LM4915 contains advanced pop & click circuitry
which virtually eliminates noises which would
otherwise occur during turn-on and turn-off
transitions.
The LM4915 has an internally fixed gain of 6dB.
1
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2
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
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