LM49251_15 Datasheet, PDF (1/41 Pages) Texas Instruments – Stereo Audio Subsystem with Class G Headphone Amplifier and Class D Speaker Amplifier with Speaker Protection

LM49251
www.ti.com
SNAS498A – FEBRUARY 2011 – REVISED APRIL 2013
LM49251
Stereo Audio Subsystem with Class G
Headphone Amplifier and Class D Speaker Amplifier with Speaker Protection
Check for Samples: LM49251
FEATURES
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•2 Class G Ground Referenced Headphone
Outputs
• E²S Class D Amplifier
• No Clip Function
• Power Limiter Speaker Protection
• I²C Volume and Mode Control
• Advanced Click-and-Pop Suppression
• Micro-Power Shutdown
APPLICATIONS
• Feature Phones
• Smart Phones
KEY SPECIFICATIONS
• Class G Headphone Amplifier, HPV_DD = 1.8V,
R_L = 32Ω
– IDDQ_HP: 1.15 mA (Typ)
– Output Power, THD+N ≤ 1%: 20 mW (Typ)
• Stereo Class D Speaker Amplifier R_L = 8Ω
– Output Power, THD+N ≤ 1%, LSV_DD = 5.0V:
1.37 W (Typ)
– Output Power, THD+N ≤ 1%, LSV_DD = 3.6V:
680 mW (Typ)
– Efficiency: 90% (Typ)
DESCRIPTION
The LM49251 is a fully integrated audio subsystem
designed for portable handheld applications such as
cellular phones. Part of TI’s PowerWise family of
products, the LM49251 utilizes a high efficiency class
G headphone amplifier topology as well as a high
efficiency class D loudspeaker.
The headphone amplifiers feature TI’s class G ground
referenced architecture that creates a ground-
referenced output with dynamic supply rails for
optimum efficiency. The stereo class D speaker
amplifier provides both a no-clip feature and speaker
protection. The Enhanced Emission Suppression
(E²S) outputs feature a patented, ultra low EMI PWM
architecture that significantly reduces RF emissions.
The LM49251 features separate volume controls for
the mono and stereo inputs. Mode selection,
shutdown control, and volume are controlled through
an I²C compatible interface.
Click and pop suppression eliminates audible
transients on power-up/down and during shutdown.
The LM49251 is available in an ultra-small 30-bump
DSBGA package (2.55mmx3.02mm)
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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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