PWM Class D amplifier circuit for automobiles

The figure below shows a high-efficiency PWM amplifier for automobiles, which can output 10W of power for a 4Ω load. IC2, N1~N6, T1, T3, R6, C5 and other components form a self-excited carrier frequency oscillator. N7~N12 are inverters connected after N1-N6, so that the output stage can use a bridge switch amplification to output greater power. IC1 is a preamplifier, which is also controlled by feedback from R6 and R7 to further reduce distortion. The output power of the amplifier is 10W, the total harmonic distortion is 0.3%, the input signal amplitude is 800mV, and the current consumption is 1.5A.