LM4898LD/NOPB

Audio Amplifiers Overview

The LM4898LD/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, or 1.4W minimum to a 4Ω load at 5V. Operating on a single supply of 2.4V to 5.5V, it eliminates the need for output coupling capacitors, snubbers, or bootstrap networks. The device features ultra-low current shutdown mode (0.1µA typical) 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
• Integrated thermal shutdown protection mechanism prevents damage during excessive heat conditions

Audio Amplifiers Applications

• Mobile phones
• PDAs
• Portable electronic devices

Audio Amplifiers Procurement Notes

Verify the specific suffix LD indicates the WSON package variant when sourcing replacements. Confirm that the NOPB designation ensures compliance with RoHS standards and absence of lead. Cross-reference the manufacturer's latest datasheet revision to ensure all electrical characteristics match the intended design requirements before finalizing procurement.

Audio Amplifiers Selection Notes

Select this component for applications requiring high output power in minimal space without external filtering components. Ensure the PCB layout accommodates the exposed die attach paddle for optimal thermal dissipation, especially when driving low impedance loads like 4Ω. Verify that the system supply voltage remains within the 2.4V to 5.5V operating range to maintain specified performance levels.

Audio Amplifiers Part Context

This part belongs to the LM4898 family of Class-AB audio amplifiers manufactured by Texas Instruments. The LM4898 series was engineered specifically for low-voltage, battery-powered portable electronics where minimizing external component count and maximizing output power are critical design constraints.

Audio Amplifiers Replacement Considerations

LM4898MM/NOPB

Audio Amplifiers FAQ

How does the shutdown functionality operate?

The LM4898 includes a shutdown mode activated by driving the Shutdown Select pin to the same logic state as the Shutdown Mode pin. The Shutdown Mode pin can be tied permanently to VDD or GND to configure the device for either shutdown-high or shutdown-low operation.

What are the thermal mounting requirements for the WSON package?

The exposed-DAP must be soldered to a copper pad connected to a large continuous copper plane acting as a heat sink. For 5V operation with a 4Ω load, a minimum heatsink area of 2.5 square inches on the same layer is recommended to prevent thermal shutdown.