LM4820-6 Datasheet, PDF (1/18 Pages) National Semiconductor (TI) – Fixed Gain 1 Watt Audio Power Amplifier

April 2002
LM4820-6
Fixed Gain 1 Watt Audio Power Amplifier
General Description
The LM4820-6 is an audio power amplifier primarily de-
signed for demanding applications in mobile phones and
other portable communication device applications. It is ca-
pable of delivering 1 watt of continuous average power to an
8Ω BTL load with less than 1% distortion (THD+N) at 6dB of
BTL gain 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 LM4820-6 does not require input
and gain resistors, output coupling capacitors or bootstrap
capacitors, and therefore is ideally suited for mobile phone
and other low voltage applications where minimal parts
count and low power consumption is a primary requirement.
The LM4820-6 features a low-power consumption shutdown
mode, which is achieved by driving the shutdown pin with
logic low. Additionally, the LM4820-6 features an internal
thermal shutdown protection mechanism.
The LM4820-6 contains advanced pop & click circuitry which
eliminates noises which would otherwise occur during
turn-on and turn-off transitions.
Key Specifications
j Improved PSRR at 217Hz
j Power Output at 5.0V & 1% THD
j Power Output at 3.3V & 1% THD
j Shutdown Current
62dB
1.0W(typ.)
400mW(typ.)
0.1µA(typ.)
Features
n Fixed 6dB BTL voltage gain
n Available in space-saving packages micro SMD, MSOP
and SOIC
n Ultra low current shutdown mode
n Can drive capacitive loads up to 500 pF
n Improved pop & click circuitry eliminates noises during
turn-on and turn-off transitions
n 2.0 - 5.5V operation
n No output coupling capacitors, snubber networks or
bootstrap capacitors required
n External gain configuration still possible
Applications
n Mobile Phones
n PDAs
n Portable electronic devices
Typical Application
FIGURE 1. Typical Audio Amplifier Application Circuit
Boomer^® is a registered trademark of National Semiconductor Corporation.
© 2002 National Semiconductor Corporation DS200106
DS200106-1
www.national.com