LM4954 Datasheet, PDF (1/16 Pages) National Semiconductor (TI) – HIgh Voltage 3 Watt Audio Power Amplifier

June 2005
LM4954
High Voltage 3 Watt Audio Power Amplifier
General Description
The LM4954 is an audio power amplifier primarily designed
for demanding applications in mobile phones and other por-
table communication device applications. It is capable of
delivering 2.4 Watts of continuous average power to an 8Ω
BTL load with less than 1% THD+N from a 7V_DC power
supply.
Boomer audio power amplifiers are designed specifically to
provide high quality output power with a minimal number of
external components. The LM4954 does not require output
coupling capacitors or bootstrap capacitors, and therefore is
ideally suited for lower-power portable applications where
minimal space and power consumption are primary require-
ments.
The LM4954 features a low-power consumption global shut-
down mode which is achieved by driving the shutdown pin
with logic low. Additionally, the LM4954 features an internal
thermal shutdown protection mechanism.
The LM4954 contains advanced pop & click circuitry which
eliminates noises that would otherwise occur during turn-on
and turn-off transitions.
The LM4954 is unity-gain stable and can be configured by
external gain-setting resistors.
Key Specifications
j Wide Power Supply
Voltage Range
2.7 ≤ V_DD ≤ 9V
j Output Power: V_DD = 7V, 1% THD+N
2.4W (typ)
j Quiescent power supply current
3mA (typ)
j PSRR: V_DD = 5V and 3V at 217Hz
j Shutdown power supply current
80dB (typ)
0.01µA (typ)
Features
n No output coupling capacitors, snubber networks or
bootstrap capacitors required
n Unity gain stable
n Externally configurable gain
n Ultra low current active low shutdown mode
n BTL output can drive capacitive loads up to 100pF
n “Click and pop” suppression circuitry
n 2.7V - 9.0V operation
n Available in space-saving microSMD package
Applications
n Mobile Phones
n PDAs
Typical Application
20129111
FIGURE 1. Typical Audio Amplifier Application Circuit
Boomer^® is a registered trademark of National Semiconductor Corporation.
© 2005 National Semiconductor Corporation DS201291
www.national.com