LM4923 Datasheet, PDF (1/23 Pages) National Semiconductor (TI) – 1.1 Watt Fully Differential Audio Power Amplifier With Shutdown Select

LM4923, LM4923LQBD
www.ti.com
SNAS211E – JULY 2004 – REVISED MAY 2013
LM4923
1.1 Watt Fully Differential Audio Power Amplifier
With Shutdown Select
Check for Samples: LM4923, LM4923LQBD
FEATURES
1
•2 Fully Differential Amplification
• Available in Space-saving WQFN Package
• Ultra Low Current Shutdown Mode
• Can Drive Capacitive Loads up to 100pF
• Improved Pop & Click Circuitry Eliminates
Noises During Turn-on and Turn-off
Transitions
• 2.4 - 5.5V Operation
• No Output Coupling Capacitors, Snubber
Networks or Bootstrap Capacitors Required
APPLICATIONS
• Mobile Phones
• PDAs
• Portable Electronic Devices
KEY SPECIFICATIONS
• Improved PSRR at 217Hz 85dB(typ)
• Power Output at 5.0V @ 1% THD+N 1.1W(typ)
• Power Output at 3.3V @ 1% THD+N
400mW(typ)
• Shutdown Current 0.1μA(typ)
DESCRIPTION
The LM4923 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 1.1 watt of continuous average power to an
8Ω BTL load with less than 1% distortion (THD+N)
from a 5V_DC power supply.
Boomer audio power amplifiers were designed
specifically to provide high quality output power with a
minimal amount of external components. The
LM4923 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 LM4923 features a low-power consumption
shutdown mode. To facilitate this, Shutdown may be
enabled by logic low. Additionally, the LM4923
features an internal thermal shutdown protection
mechanism.
The LM4923 contains advanced pop & click circuitry
which eliminates noises which would otherwise occur
during turn-on and turn-off transitions.
Connection Diagrams
V_O-
8
IN-
1
GND
7
6
BYP
IN+ 2
3
5 SD
4
IN-
IN+
V_DD
V_O+
V_O-
GND
BYP
SD
V_DD
V_O+
Figure 1. NGP Package, Top View
See Package Number NGP0008A
Figure 2. 8 Pin VSSOP Package, Top View
See Package Number DGK0008A
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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