Mixed-Signal Design of a Digital Input Power Amplifier for Automotive Audio Applications

With reference to digital input power amplifier for automotive audio applications, the paper presents an exhaustive exploration of the huge mixed-signal space to find optimal trade-offs among different cost-functions: distortion, efficiency, circuit complexity and sensitivity. Different architectural solutions are modelled and compared in a Simulink/Spice framework. All building blocks (i.e. oversampling filter, noise shaping, type of PWM modulation, type of feedback, power stage, LC filter) are optimized considering the whole system performance. A novel mixed-signal scheme is finally derived and prototyped