Practical Circuit LM3875 - Dual Power

Description: The 875T and LM3876T are high-performance 40W power amplifier integrated circuits (ICs). They operate within a frequency range of 20Hz to 20kHz with a continuous average power output under an 8-ohm load and exhibit a distortion level of only 0.05%. These characteristics make them preferred choices for manufacturers designing high-fidelity audio equipment. While both circuits share similar performance parameters, they differ slightly in power supply voltage range, conversion rates, and quiescent supply current. The consistency in circuit performance and high reliability makes them suitable for mass production of electronic products. The electrical performance of the amplifier circuits is detailed in Table 2-14. Figure 2-57 illustrates two applications for the LM3875 circuit, showcasing the simplicity and flexibility of the external circuits. The LM3875T can operate with dual power supplies or a single power supply. The supply voltage range for the dual power supply is 10 to 40V, with a quiescent current of approximately 30mA. When powered at 35V with a load, the distortion is 0.2%, and the output power reaches 56W. Within the frequency range of 20Hz to 20kHz, the output power is 40W, and the total harmonic distortion plus noise is limited to 0.05%. Under standard operating conditions, the frequency response is from 5Hz to 100kHz (+0.25dB), and the signal-to-noise ratio (SNR) reaches 115dB (A-weighted), with a conversion rate of 11V/µs. The LM3876T has a supply voltage range of 7 to 47V, with a quiescent current of approximately 40µA (mute off). Its performance is similar to that of the LM3875T, but the LM3876T includes a mute control feature, which is absent in the LM3875T.

The 875T and LM3876T amplifier ICs are designed for high-fidelity audio applications, providing robust performance with minimal distortion. The LM3875T configuration allows for flexibility in power supply arrangements, making it adaptable for various audio design requirements. The dual power supply option enables designers to optimize performance for different load conditions, while the single supply configuration simplifies circuit design for compact applications.

In terms of specifications, the LM3875T's output power capabilities allow it to drive speakers effectively while maintaining high audio quality. The low distortion figures indicate that the amplifier can reproduce audio signals with fidelity, making it suitable for use in high-end audio systems. The frequency response range further ensures that the amplifier can handle a wide spectrum of audio frequencies, from deep bass to high treble, without significant loss of quality.

The LM3876T, with its mute control feature, offers additional versatility for applications where audio interruption is needed, such as in consumer electronics. The quiescent current specifications for both ICs indicate low power consumption in standby modes, enhancing their suitability for battery-operated devices.

Both ICs are characterized by high reliability and consistent performance, making them ideal for mass production in the consumer electronics market. Their design and manufacturing processes adhere to strict quality standards, ensuring that they meet the demands of modern audio equipment. Overall, the 875T and LM3876T represent a compelling choice for engineers seeking to design high-performance audio amplification solutions.875T and LM3876T same high performance 40W high power amplifier IC. It can 20Hz - 20kHz frequency range within continuous average power output load 8fl deleted, only 0,05% dist ortion. Therefore, it is the manufacturers design and manufacture of high-fidelity audio equipment preferred amplifier IC. In addition to the two circuits in the power supply voltage range, a slightly different conversion rates and quiescent supply current, the same as the other parameters.

Circuit performance consistency, and high reliability, especially not suitable for Taiwan to use for mass production of electronic products. Both electrical performance amplifier circuit as shown in Table 2-14. Figure 2-57 two applications for the LM3875 circuit. The figure shows the external circuit of the two circuit is relatively simple, but also very flexible oLM3875T can use dual power, also can use a single power supply.

LM3875T: supply voltage range, dual power supply is 10 ~ 40V; quiescent current of about 30mA; when the power supply when pressure is 35V, load goblets, distortion of 0.2%, the output power is 56W; in the frequency range 20hz ~ 20kHz, output power of 40W, the total harmonic distortion plus noise crossing the 0.05%; when the standard operation conditions, frequency response SHz ~ lOOkHz (+ 0,25dB), SNR up to 115dB (a-weighted), conversion rate 11V4150 LM3876T: supply voltage range, when the power supply is taken 7 ~ 47V; quiescent current of about 40n1A (mute off); the same as the rest of the performance and LM3875T, LM3876T only with mute control, LM3875T no mute function.