LM48821 Datasheet, PDF (1/24 Pages) National Semiconductor (TI) – Direct Coupled, Ultra Low Noise, 52mW Differential Input Stereo Headphone Amplifier with I2C Volume Control

LM48821, LM48821TLEVAL
www.ti.com
SNAS354A – JUNE 2007 – REVISED MAY 2013
LM48821
Direct Coupled, Ultra Low Noise, 52mW
Differential Input Stereo Headphone Amplifier with I2C Volume Control
Check for Samples: LM48821, LM48821TLEVAL
FEATURES
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•2 Ground Referenced Outputs
• Differential Inputs
• I²C Volume and Mode Controls
• Available in Space-Saving DSBGA Package
• Ultra Low Current Shutdown Mode
• Advanced Output Transient Suppression
Circuitry Eliminates Noises During Turn-On
and Turn-Off Transitions
• 2.0V to 4.0V Operation (PV_DD and SV_DD)
• 1.8 to 4.0V Operation (I²CV_DD)
• No Output Coupling Capacitors, Snubber
Networks, Bootstrap Capacitors, or Gain-
Setting Resistors Required
APPLICATIONS
• Notebook PCs
• Desktop PCs
• Mobile Phones
• PDAs
• Portable Electronic Devices
• MP3 Players
KEY SPECIFICATIONS
• Improved PSRR at 217Hz: 82dB (typ)
• Stereo Output Power at VDD = 3V, RL = 16Ω,
THD+N = 1%: 52mW (typ)
• Mono Output Power at VDD = 3V, RL = 16Ω,
THD+N = 1%: 93mW (typ)
• Shutdown current: 0.1μA (typ)
DESCRIPTION
With its directly-coupled output technology, the
LM48821 is a variable gain audio power amplifier
capable of delivering 52mW_RMS per channel into a
16Ω single-ended load with less than 1% THD+N
from a 3V power supply. The I²C volume control has
a range of –76dB to 18dB.
The LM48821's Tru-GND technology utilizes
advanced charge pump technology to generate the
LM48821’s negative supply voltage. This eliminates
the need for output-coupling capacitors typically used
with single-ended loads.
Boomer audio power amplifiers were designed
specifically to provide high quality output power with a
minimal amount of external components. The
LM48821 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 LM48821 incorporates selectable low-power
consumption shutdown and channel select modes.
The LM48821 contains advanced output transient
suppression circuitry that eliminates noises which
would otherwise occur during turn-on and turn-off
transitions.
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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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