LM4938 Datasheet | National Semiconductor

Description The LM4938 is a monolithic integrated circuit that provides DC 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 LM4938 incorporates a DC volume control, stereo bridged audio power amplifiers and a selectable gain or bass boost, making it optimally suited for multimedia monitors, portable radios, desktop, and portable puter applications. The LM4938 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, LM4938MH will deliver 2W into 4Ω. See Application Information section Exposed-DAP package PCB Mounting Considerations for more information. Note 2: An LM4938MH that has 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 n into 4Ω n into 8Ω n Single-ended mode - THD+N at 92m W into 32Ω n Shutdown current 2.2W (typ) 2.0W (typ) 1.3W (typ) 1.0%(typ) 0.5µA (typ) Features n Improved click and pop circuitry virtually eliminates noise during turn on/off transitions n DC Volume Control Interface n System Beep Detect n Stereo switchable bridged/single-ended power amplifiers n Selectable internal/external gain and bass boost n Thermal shutdown protection circuitry n Unity gain stable Applications n n n n Flat Panel Displays Portable and Desktop puters Multimedia Monitors Portable Radios, PDAs, and Portable TVs Block Diagram FIGURE 1. LM4938 Block Diagram Boomer ® is a registered trademark of National Semiconductor Corporation. © 2005 National Semiconductor Corporation DS200956 .national. Connection Diagram TSSOP...