LM4840MH/NOPB

Audio Amplifiers Overview

The LM4840MH/NOPB is a stereo audio power amplifier manufactured by Texas Instruments, formerly National Semiconductor. It integrates digital volume control and an input multiplexer within a single package. The device delivers 2W of continuous output power into a 4Ω load with less than 1% total harmonic distortion plus noise at a 5V supply voltage. It operates from a single power supply ranging from 2.7V to 5.5V. The component utilizes a microSmallOutline package (MSOP) with ten exposed pads for thermal dissipation.

Audio Amplifiers Feature Summary

• Integrates digital volume control allowing adjustment via serial interface
• Includes an input multiplexer for selecting between multiple audio sources
• Capless output design eliminates the need for large coupling capacitors
• Supports transient-free shutdown mode to minimize pop-and-click noises

Audio Amplifiers Applications

• Portable media players requiring integrated volume management
• Mobile phones and smartphones with limited board space
• Personal digital assistants (PDAs)
• MP3 players and portable audio devices

Audio Amplifiers Procurement Notes

Verify the manufacturer marking on the component body to distinguish between original National Semiconductor production and post-acquisition Texas Instruments manufacturing. Confirm the presence of the NOPB suffix indicates lead-free and RoHS compliance. Ensure the MSOP-10 package variant matches the specific thermal pad requirements of the target PCB layout.

Audio Amplifiers Selection Notes

Select this component when a design requires both amplification and digital volume control in a compact form factor. It is suitable for applications where saving board area by removing external volume potentiometers is critical. Consider the input mux feature if the system needs to switch between different audio inputs without additional switching components.

Audio Amplifiers Part Context

This part belongs to the LM484x series of stereo audio amplifiers from National Semiconductor. The series is characterized by high efficiency and low distortion capabilities designed for battery-powered consumer electronics. The LM4840 specifically adds digital control features compared to basic analog-only variants in the same family.

Audio Amplifiers FAQ

What is the maximum supply voltage for the LM4840MH/NOPB?

The device supports a single supply voltage range from 2.7V to 5.5V.

Does the LM4840 require output coupling capacitors?

No, it features a capless output design that drives loads directly without external coupling capacitors.