1FEATURES
2• Selectable Gain of 6dB (2V/V) or 12dB (4V/V)
• No Output or PSRR Bypass Capacitors
Required
• Improved “Click and Pop” Suppression
Circuitry
• Very Fast Turn on Time: 5ms (Typ)
• Minimum External Components
• 2.6 - 5.5V Operation
• BTL Output Can Drive Capacitive Loads
• Ultra Low Current Shutdown Mode (SD Low)

APPLICATIONS
• Portable Computers
• Desktop Computers
• Multimedia Monitors

KEY SPECIFICATIONS
• Improved PSRR at 217Hz for +3V: 71 dB
• Power Output at +5V, THD+N = 1%, 8Ω: 1.0 W
(Typ)
• Power Output at +3V, THD+N = 1%, 8Ω: 390
mW (Typ)
• Total Shutdown Power Supply Current: 0.1μA
(Typ)

DESCRIPTION
The LM4906 is an audio power amplifier primarily
designed for demanding applications in mobile
phones and other portable communication device
applications. It is capable of delivering 1W of
continuous average power to an 8Ω BTL load with
less than 1% distortion (THD+N) from a +5V power
supply.
The LM4906 is the first Texas Instruments Boomer
Power Amplifier that does not require an external
PSRR bypass capacitor. The LM4906 also has an
internal selectable gain of either 6dB or 12dB. In
addition, no output coupling capacitors or bootstrap
capacitors are required which makes the LM4906
ideally suited for cell phone and other low voltage
portable applications.
The LM4906 contains advanced pop and click circuitry that eliminates noise, which would otherwise
occur during turn-on and turn-off transitions.
Boomer audio power amplifiers were designed
specifically to provide high quality output power with a
minimal amount of external components. The
LM4906 features a low -power consumption
shutdown mode (the part is enabled by pulling the SD
pin high). Additionally, the LM4906 features an
internal thermal shutdown protection mechanism.