LM4953 Datasheet, PDF (1/11 Pages) National Semiconductor (TI) – Ground-Referenced, Ultra Low Noise, Ceramic Speaker Driver

September 2005
LM4953
Ground-Referenced, Ultra Low Noise, Ceramic Speaker
Driver
General Description
The LM4953 is an audio power amplifier designed for driving
Ceramic Speaker in portable applications. When powered by
a 3.6V supply, it is capable of forcing 12.6Vpp across a 2µF
+ 30Ω bridge-tied-load (BTL) with less than 1% THD+N.
Boomer audio power amplifiers were designed specifically to
provide high quality output power with a minimal amount of
external components. The LM4953 does not require boot-
strap capacitors, or snubber circuits. Therefore it is ideally
suited for display applications requiring high power and mini-
mal size.
The LM4953 features a low-power consumption shutdown
mode. Additionally, the LM4953 features an internal thermal
shutdown protection mechanism.
The LM4953 contains advanced pop & click circuitry that
eliminates noises which would otherwise occur during
turn-on and turn-off transitions.
The LM4953 is unity-gain stable and can be configured by
external gain-setting resistors.
Key Specifications
j Quiescent Power Supply Current (V_dd = 3V) 7mA(typ)
j BTL Voltage Swing
(2µF+30Ω load, 1% THD+N,
V_dd = 3.6V)
12.6V_pp (typ)
j Shutdown Current
1µA (max)
Features
n Pop & click circuitry eliminates noise during turn-on and
turn-off transitions
n Low, 1µA (max) shutdown current
n Low, 7mA (typ) quiescent current
n 12.6Vpp mono BTL output, load = 2µF+ 30Ω
n Thermal shutdown
n Unity-gain stable
n External gain configuration capability
Applications
n Cellphone
n PDA
Typical Application
FIGURE 1. Typical Application Circuit
Boomer^® is a registered trademark of National Semiconductor Corporation.
© 2005 National Semiconductor Corporation DS201421
20142168
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