LM4702BTA/NOPB

Audio Amplifiers Overview

The LM4702BTA/NOPB is a stereo high-fidelity audio power amplifier driver from Texas Instruments, designed for demanding consumer and professional applications. It operates with supply voltages ranging from ±20V to ±100V. The device features thermal shutdown circuitry that activates at 150°C and a mute function to force outputs to a quiescent state. Key electrical specifications include a typical Power Supply Rejection Ratio (PSRR) of 110dB, an equivalent noise of 3μV, and a Total Harmonic Distortion plus Noise (THD+N) of 0.0003% at A and B grades.

Audio Amplifiers Feature Summary

• Supports very high voltage operation up to ±100V
• Includes integrated thermal shutdown protection
• Features external mute functionality
• Offers scalable output power via supply voltage adjustment

Audio Amplifiers Applications

• AV Receivers
• Audiophile Power Amplifiers
• Professional Audio Systems
• High Voltage Industrial Applications

Audio Amplifiers Procurement Notes

Verify the specific package type and grade requirements against the datasheet before procurement. Confirm that the selected heat sink meets thermal resistance calculations to prevent activation of the internal thermal shutdown circuitry during normal operation. Ensure input bias resistors and coupling capacitors are selected to maintain stability and desired low-frequency response characteristics.

Audio Amplifiers Selection Notes

Select the LM4702BTA/NOPB for designs requiring high voltage headroom and low distortion. Consider the total supply voltage when calculating maximum power dissipation, as quiescent current remains relatively constant. Ensure proper PCB layout to minimize crosstalk and use emitter degeneration resistors or Vbe multipliers if utilizing bipolar output stages to prevent thermal runaway.

Audio Amplifiers Part Context

The LM4702 belongs to the Overture Audio Power Amplifier Series by Texas Instruments. This series includes multiple grades such as the LM4702C for general applications and the LM4702A for premium performance. The LM4702B provides higher voltage ratings and tighter specifications compared to lower grades, making it suitable for high-performance audio systems.

Audio Amplifiers Replacement Considerations

LM4702C/NOPB

Audio Amplifiers FAQ

How is the mute function controlled on the LM4702?

The mute function is controlled by the current flowing into the mute pin. Currents below 1mA mute the input drive signal, while currents between 1mA and 2mA place the part in 'play' mode.

What happens when the die temperature exceeds 150°C?

When the die temperature exceeds 150°C, the LM4702 activates its thermal shutdown circuitry. It resumes operation when the temperature drops to approximately 145°C.