LM4925SD/NOPB

Audio Amplifiers Overview

The LM4925SD/NOPB is a stereo audio power amplifier from the Boomer AudioPowerAmplifierSeries2Cell, SingleEndedOutput family. It operates on a single supply voltage ranging from 1.5V to 3.6V. In single-ended headphone mode, it delivers 40mW per channel into a 16Ω load at 1% THD+N with a 3.0V supply. In bridged-tied load (BTL) mono speaker mode, it provides 410mW into an 8Ω load under identical conditions. The device features micro-power shutdown current of 0.1µA and includes click-and-pop suppression circuitry.

Audio Amplifiers Feature Summary

• Supports both single-ended stereo headphone operation and bridged-tied load mono speaker configurations via external pin control.
• Integrates click-and-pop suppression circuitry to minimize output transients during device turn-on and turn-off events.
• Includes active-low micro-power shutdown and mute modes for extended battery life in portable applications.

Audio Amplifiers Applications

• Portable two-cell audio products
• Portable two-cell electronic devices

Audio Amplifiers Procurement Notes

Verify the package type matches the specific suffix requirements for your PCB layout, as the LM4925 is available in VSSOP and SON packages. Confirm that the operating supply voltage range aligns with your system's battery configuration between 1.5V and 3.6V. Ensure thermal management considerations are addressed if operating near maximum power dissipation limits in BTL mode.

Audio Amplifiers Selection Notes

Select this component when designing low-voltage portable audio systems requiring minimal external components. Choose the single-ended mode for stereo headphone applications driving 16Ω loads. Opt for the bridged-tied load configuration when higher power output is needed for mono speakers with 8Ω impedance. Consider the micro-power shutdown feature for battery-operated devices requiring long standby times.

Audio Amplifiers Part Context

The LM4925 belongs to Texas Instruments' Boomer series, designed specifically for high-quality output power in surface-mount packages while minimizing PCB area. It integrates two operational amplifiers within a single package, allowing for flexible stereo or mono bridged configurations without requiring complex external biasing networks.

Audio Amplifiers Replacement Considerations

LM4924MM/NOPB: Offers similar stereo headphone functionality but lacks the BTL speaker capability and has lower output power specifications.

Audio Amplifiers FAQ

How is the operating mode selected between single-ended and BTL?

The SE/BTL pin determines the mode. Applying a logic high (VDD) configures the device for BTL mode, while applying a logic low (GND) sets it to single-ended mode.

What is the purpose of the bypass capacitor connected to the BYP pin?

The bypass capacitor stabilizes the internal bias generator. A value between 0.1μF and 4.7μF is recommended to ensure proper power supply rejection and stability.