LM2876 40W audio power amplifier circuit design
this 40W audio power amplifier circuit is designed using the LM2876 audio power amplifier ic capable of delivering 40W of continuous average power to an 8Ω load with 0.1% THD+N from 20Hz–20kHz.
The LM2876 40W audio power amplifier circuit operates over a wide input voltage range , from 20 up to 70 volts , but typically a dual 30 volt power supply ( or a single 60 volt in this case ) will be work fine .
The LM2876 maintains an excellent signal-to-noise ratio of greater than 95dB (min) with a typical low noise floor of 2.0μV.
The muting function of the LM2876 allows the user to mute the music going into the amplifier by drawing less than 0.5 mA out of pin 8 of the device.
The LM2876 contains overvoltage protection circuitry that limits the output current to approximately 4Apeak while also providing voltage clamping, though not through internal clamping diodes.
The LM2876 has a sophisticated thermal protection scheme to prevent long-term thermal stress to the device. When the temperature on the die reaches 165°C, the LM2876 shuts down. It starts operating again when the die temperature drops to about 155°C