1 Watt Audio Power Amplifier - National Semiconductor

The LM4903 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 1 watt of continuous average power to an 8 BTL load with less than 1% distortion (THD+N) from a 5VDC power supply. Boomer Audio Power Amplifiers were designed specifically to provide high quality output power with a minimal amount of external components. The LM4903 does not require output coupling capacitors or bootstrap capacitors, and therefore is ideally suited for mobile phone and other low voltage appli- cations where minimal power consumption is a primary re- quirement. The LM4903 features a low-power consumption shutdown mode, which is achieved by driving the shutdown pin with Logic low. Additionally, the LM4903 features an internal ther- mal shutdown protection mechanism. The LM4903 contains advanced pop & click circuitry which eliminates noise which would otherwise occur during turn-on and turn-off transitions. The LM4903 is unity-gain stable and CAN be configured by external gain-setting resistors. By National Semiconductor Corporation