LM4898MMX/NOPB

Audio Amplifiers Overview

The LM4898MMX/NOPB is a fully differential audio power amplifier designed for mobile phones and portable communication devices. It delivers 1W continuous average power to an 8Ω BTL load from a 5VDC supply with less than 1% THD+N. Operating on a single supply voltage ranging from 2.4V to 5.5V, it eliminates the need for output coupling capacitors, snubber networks, or bootstrap capacitors. The device features ultra-low current shutdown mode (0.1µA typ) with high or low selectivity, improved pop and click circuitry, and thermal shutdown protection.

Audio Amplifiers Feature Summary

• Fully differential amplification architecture providing bridged-tied-load (BTL) output drive without external coupling capacitors
• Ultra-low current shutdown mode with selectable logic level activation via dedicated Shutdown Mode pin
• Advanced pop and click circuitry virtually eliminates audible noises during turn-on and turn-off transitions
• Internal thermal shutdown protection mechanism safeguards against excessive junction temperatures

Audio Amplifiers Applications

• Mobile phones
• PDAs
• Portable electronic devices

Audio Amplifiers Procurement Notes

Verify the specific package suffix matches the required footprint; MMX denotes VSSOP-10. Confirm NOPB indicates lead-free/RoHS compliance. Check datasheet revision SNAS216E for updated electrical limits. Ensure PCB layout adheres to exposed-DAP thermal requirements if using WSON variants, though MMX uses VSSOP. Validate input resistor matching for optimal CMRR performance.

Audio Amplifiers Selection Notes

Select this component for applications requiring high output power in minimal space without external inductors or large capacitors. Suitable for battery-operated systems due to low quiescent current and efficient shutdown modes. Requires matched feedback and input resistors to maintain common-mode rejection and prevent DC load currents. Ideal for single-supply operation where bridge-tied-load topology maximizes voltage swing.

Audio Amplifiers Part Context

Part of Texas Instruments' Boomer audio power amplifier family, specifically engineered for low-voltage, high-efficiency audio applications. The LM4898 series includes variants like LM4898LD and LM4898ITL, differing primarily in packaging and thermal characteristics. Designed to replace older Class-AB amplifiers that required complex external biasing and filtering networks.

Audio Amplifiers Replacement Considerations

LM4898MMX

Audio Amplifiers FAQ

How is the shutdown function configured?

Shutdown can be enabled by driving the Shutdown Select pin high or low, depending on the state of the Shutdown Mode pin. Tying the Shutdown Mode pin to VDD or GND sets the device as 'shutdown-high' or 'shutdown-low' respectively.

Does the LM4898 require output coupling capacitors?

No, the fully differential BTL configuration eliminates the need for output coupling capacitors, snubber networks, or bootstrap capacitors, making it suitable for low-voltage mobile applications.