40W 4 channel audio amplifier

The integrated audio TDA8571J, designed for automotive applications, allows for the expansion of car radio sound or the connection of a portable MP3 player. Internally, the chip contains eight operational amplifiers set in a bridge configuration, enabling each speaker terminal to be energized. It is important not to connect the negative terminal of the speaker's mass, as this may create a short circuit at the output. This circuit supports a total of four speakers with a 4-ohm impedance and operates at 40W with a 12V power supply, making it suitable for use in vehicles. The total harmonic distortion is relatively high, approximately 10% at full power; however, at half the power (20W), it drops to less than 2%. This system is not designed for high-performance audio applications in vehicles.

The TDA8571J audio amplifier circuit is specifically tailored for automotive environments, providing a robust solution for enhancing audio output from factory-installed car radios or integrating with external audio sources such as MP3 players. The architecture of the TDA8571J features a bridge amplifier configuration, which effectively doubles the output voltage across the speakers, thereby maximizing sound output while maintaining a compact design.

The circuit is designed to drive four speakers, each with a nominal impedance of 4 ohms, which is a common configuration in automotive audio systems. The amplifier delivers a maximum output power of 40W at a supply voltage of 12V, making it capable of producing adequate sound levels for typical vehicle acoustics.

When implementing this circuit, attention must be paid to the connection of the speaker terminals. The negative terminal should not be connected to the ground or mass of the vehicle, as this could lead to a short circuit and potential damage to the amplifier.

The performance characteristics of the TDA8571J reveal that while the total harmonic distortion (THD) is around 10% at maximum output, it significantly improves to below 2% when operating at a reduced output of 20W. This indicates that the amplifier, while not intended for high-fidelity audio reproduction, can still provide a satisfactory listening experience for everyday automotive use.

Overall, the TDA8571J provides a cost-effective solution for enhancing audio in vehicles, accommodating a variety of audio sources while ensuring reliability and ease of integration.With the integrated audio TDA8571J designed for automotive applications, this circuit can expand the sound of the car radio or connect a portable MP3 playerin it. Internally, thechiphas eightoperationalamplifierseton the bridge, allowingeachspeaker terminalbeing energized.

Dontconnect thenegative terminal ofthe mass ofthe speaker, becausetheywillproducea short circ uiton theoutput. This circuitprovidesa total of fourspeakers4 ohmsand40Wat12vpowered. It is thereforeidealfor usein the car. Totalharmonic distortionis rather high, about 10%at full power. Butwithhalf the powerrequirements(20W)is lessthan 2%. Anyway itis not intendedtohave ahigh performancesystemin the car. With theintegratedaudioTDA8571Jdesignedforautomotive applications, this 40w amplifier circuit can expandthe soundof the car radioorconnecta. 🔗 External reference