LM4991 Datasheet | National Semiconductor

LM4991 3W Audio Power Amplifier with Shutdown Mode May 2003 LM4991 3W Audio Power Amplifier with Shutdown Mode General Description The LM4991 is a mono bridged audio power amplifier capable of delivering 3W of continuous average power into a 3Ω load with less than 10% THD when powered by a 5V power supply (Note 1). To conserve power in portable applications, the LM4991’s micropower shutdown mode (ISD = 0.1µA, typ) is activated when VDD is applied to the SHUTDOWN pin. Boomer audio power amplifiers are designed specifically to provide high power, high fidelity audio output. They require few external ponents and operate on low supply voltages from 2.2V to 5.5V. Since the LM4991 does not require output coupling capacitors, bootstrap capacitors, or snubber networks, it is ideally suited for low-power portable systems that require minimum volume and weight. Additional LM4991 Features include thermal shutdown protection, unity-gain stability, and external gain set. Note 1: An LM4991LD that has been properly mounted to a circuit board will deliver 3W into 3Ω (at 10% THD). The other package options for the LM4991 will deliver 1.5W into 8Ω (at 10% THD). See the Application Information sections for further information concerning the LM4991LD and LM4991M. Key Specifications n Improved PSRR at 217k Hz and 1k Hz 64d B (typ) n PO at VDD = 5.0V, 10% THD, 1k Hz n LM4991LD (only), 3Ω, 4Ω 3W (typ), 2.5W (typ) n All packages, 8Ω load 1.5W (typ) n Shutdown current 0.1µA (typ) Features Available in space-saving LLP and MA packages Ultra low current shutdown mode Can drive capacitive loads up to 500p F Improved pop & click circuitry reduces noises during turn-on and turn-off transitions n 2.2 - 5.5V operation n No output coupling capacitors, snubber networks, bootstrap capacitors or gain-setting resistors required n Unity-gain stable n n n n Applications n n n n Wireless and cellular handsets PDA’s Portable puters Desktop puters Connection Diagrams Small Outline Package LLP...