LA4708N-E

Audio Amplifiers Overview

The LA4708N is a monolithic linear integrated circuit designed for car stereo applications, functioning as a 2-channel BTL audio power amplifier. It utilizes an NF capacitor-less circuit to enhance low-frequency response and reduce crosstalk. The device supports a total output of 30W + 30W at VCC = 13.2V with THD at 30% into 4Ω loads, or 30W per channel at 10% THD into 2Ω loads. Key electrical characteristics include a quiescent current of 150mA typical, voltage gain of 40dB, and ripple rejection ratio of 50dB. Operating conditions range from 9V to 16V supply voltage.

Audio Amplifiers Feature Summary

• NF capacitor-less architecture improves low-region frequency characteristics and reduces crosstalk for clearer sound quality.
• Integrated standby switch circuit allows microprocessor control for power management.
• Comprehensive on-chip protection systems include output-to-ground short, output-to-VCC short, load short, overvoltage, and thermal shutdown circuits.
• Pop noise prevention mechanism with adjustable on-time via external capacitor.

Audio Amplifiers Applications

• Car stereo audio amplification
• Automotive head unit power stages
• BTL two-channel audio systems

Audio Amplifiers Procurement Notes

Verify the manufacturer origin, as the datasheet references SANYO Semiconductor Co., Ltd. while the ordering number ENA1783 may indicate subsequent corporate restructuring or acquisition. Confirm package type SIP18H matches design requirements. Ensure application notes regarding heat sink area and allowable power dissipation are reviewed before finalizing board layout to prevent thermal shutdown during operation.

Audio Amplifiers Selection Notes

Select this component for automotive audio designs requiring high power output in a compact form factor. Consider the 2Ω load support if space constraints limit speaker impedance. Evaluate thermal management needs carefully, as the maximum allowable power dissipation is 37.5W. The standby pin functionality requires specific resistor calculations if voltages exceed standard levels to ensure proper current limiting and reliable switching behavior.

Audio Amplifiers Part Context

The LA4708N belongs to the family of monolithic linear ICs developed specifically for car stereos. It represents a solution for achieving excellent sound quality through improved circuit and pattern layout. The device integrates power amplification with necessary protection features, simplifying the design process for automotive audio engineers by reducing the need for external protective components.

Audio Amplifiers Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation. Designers should consult the manufacturer for updated product lines or equivalent offerings if discontinuation occurs.

Audio Amplifiers FAQ

How is the amplifier on-time controlled?

The on-time is set by an external capacitor connected to Pin 6. The duration is proportional to the capacitance value; for example, a 33μF capacitor results in approximately 0.8 seconds of on-time.

What is the function of Pin 5?

Pin 5 is the standby switch input. Applying approximately 2.5V or more to this pin through an external resistor turns the amplifier on.

How can pop noise be further reduced?

An electrolytic capacitor between 0.47μF and 2.2μF can be connected between Pin 8 (bias pin) and Pre-GND to further reduce pop noise during power-on/off transitions.