LM4891M/NOPB

Audio Amplifiers Overview

The LM4891M/NOPB is a Boomer audio power amplifier designed for mobile phones and portable communication devices. It delivers 1 watt of continuous average power to an 8-ohm bridge-tied load (BTL) with less than 1% distortion from a 5V DC supply. The device operates within a voltage range of 2.2V to 5.5V and features ultra-low current shutdown mode, improved pop and click circuitry, thermal shutdown protection, and unity-gain stability.

Audio Amplifiers Feature Summary

• Ultra-low current shutdown mode minimizes power consumption when disabled
• Advanced pop and click circuitry eliminates noises during turn-on and turn-off transitions
• Bridge-tied output configuration drives capacitive loads without external coupling capacitors
• Internal thermal shutdown mechanism protects the device under fault conditions

Audio Amplifiers Applications

• Mobile phones
• PDAs
• Portable electronic devices

Audio Amplifiers Procurement Notes

Verify component authenticity through authorized Texas Instruments distributors or certified partners. Confirm the part number matches the specific package variant required for your design. Review the official datasheet for absolute maximum ratings and operating conditions to ensure compatibility with your system's electrical environment before finalizing procurement.

Audio Amplifiers Selection Notes

Select this amplifier for low-voltage applications requiring high efficiency and minimal external components. Ensure the PCB layout accommodates the chosen package style for optimal thermal performance. Verify that the input signal levels match the unity-gain stable configuration requirements to achieve desired output power without excessive distortion.

Audio Amplifiers Part Context

The LM4891 belongs to Texas Instruments' Boomer audio power amplifier series, engineered specifically for portable electronics. This series emphasizes high-quality output power with minimal external component counts. The LM4891 utilizes a dual operational amplifier architecture configured for bridged operation, distinguishing it from single-ended amplifiers by eliminating the need for output coupling capacitors.

Audio Amplifiers Replacement Considerations

The LM4891 is marked as obsolete in official documentation. Engineers should consult the manufacturer for recommended replacement parts or alternative solutions suitable for new designs.