A Class D audio amplifier is essentially a PWM amplifier. The input audio signal is used as the modulation reference for a PWM carrier. The resulting PWM signal Op amp OA2 is used in the triangle generator as an integrator, with its output fed back to the window comparator to create an oscillator. class d amplifier pwm generator Direct Digital Pulse Width Modulation for Class D Amplifiers Design a pulse generator based on a hybrid of a counter and a tapped delayline with the aim to reach certain requirements and to minimize power consumption and chip area.
The Class D amplifier is therefore nothing more than a combination of a pulse width modulator (PWM) and a digital power stage and subsequent lowpass filter. Fig. 1 shows the elements of such an amplifier with analog input in halfbridge topology. class d amplifier pwm generator
The most common modulation technique is pulsewidth modulation (PWM). Conceptually, PWM compares the input audio signal to a triangular or ramping waveform that runs at a fixed carrier frequency. This creates a stream of pulses at the carrier frequency. PWM and ClassD Amplifiers with ADSPBF535 Blackfin PWM (pulsewidth modulation) forms the basis for a very efficient form of power amplification. The circuit in figure 1 is a socalled class D power amplifier since the actual power amplification is provided to the PWM signal, and since it is of constant amplitude. This concept is extremely useful in many applications such as ClassD audio amplifiers, switching power supplies, optical transmission, and conveying analog information through 4 Analog Pulse Width Modulation SLAU508June 2013Revised June 2013 amplifier and the triangle wave generator portions of the circuit. Examining at the triangle class d amplifier pwm generator This application note describes Class D Amplifiers (called DAMP hereafter) guideline to enable customers to control DAMP correctly in their application. PWM Generator generates a PWM signal with 1 bit width based on DeltaSigma Modulator output and its period is 124 Fs. AN1071 2 www. irf. com What is a Class D Audio Amplifier Theory of Operation A Class D audio amplifier is basically a switching amplifier or PWM amplifier. Micropower LowVoltage Digital Class D Amplifier for Hearing Aid Applications by PWM Pulse Generator class D amplifier , IEEE Transactions on Circuits and Systems II: Analog and Digital Signal Processing (Regular Paper),