LM4840 Datasheet | National Semiconductor

Description The LM4840 is a monolithic integrated circuit that provides digital volume control and stereo bridged audio power amplifiers capable of producing 2W into 4Ω (Note 1) with less than 1.0% THD or 2.2W into 3Ω (Note 2) with less than 1.0% THD. Boomer ® audio integrated circuits were designed specifically to provide high quality audio while requiring a minimum amount of external ponents. The LM4840 incorporates a digital volume control, stereo bridged audio power amplifiers, an input mux, and a last volume level memory function to save the volume setting during shutdown. These features make it optimally suited for multimedia monitors, portable radios, desktop, and portable puter applications. The LM4840 features an externally controlled, low-power consumption shutdown mode, and both a power amplifier and headphone mute for maximum system flexibility and performance. Note 1: When properly mounted to the circuit board, the LM4840LQ and LM4840MH will deliver 2W into 4Ω. The LM4840MT will deliver 1.1W into 8Ω. See the Application Information section LM4840LQ and for LM4840MH usage information. Note 2: An LM4840LQ and LM4840MH that have been properly mounted to the circuit board and forced-air cooled will deliver 2.2W into 3Ω. Key Specifications n PO at 1% THD+N n into 3Ω (LM4840LQ, LM4840MH) 2.2W (typ) n into 4Ω (LM4840LQ, LM4840MH) 2.0W (typ) n into 8Ω (LM4840) 1.1W (typ) n Single-ended mode - THD+N at 85m W into 32Ω 1.0% (typ) n Shutdown current 0.2µA (typ) Features n n n n n n n n n PC98 and PC99 pliant Digital Volume Control Interface System Beep Detect Stereo switchable bridged/single-ended power amplifiers “Click and pop” suppression circuitry Thermal shutdown protection circuitry Input Mux Capless headphone drivers Last volume memory from shutdown Applications n Portable and Desktop puters n Multimedia Monitors n Portable Radios, PDAs, and Portable TVs Connection Diagram LLP Package DS200104-35 Top View Order Number LM4840LQ See NS Package Number...