An enhanced class-d amplifier architecture
This dissertation presents several enhancements to the standard digital-input Class-D amplifier structure. Improvements are made both in the conversion process where the standard CD audio Pulse Code Modulation (PCM) signal is encoded in a Pulse Width Modulation (PWM) scheme as well as in the power amplification stage where the PWM signal is amplified to allow for proper load driving power. Theory is developed as a means of demonstrating the power of the enhancements, SIMULINK and MATLAB simulations are then used to verify the introduced theory. The structure is then taken through the schematic design and integrated circuit layout using the CADENCE design environment and fabricated through the MOSIS design foundry. The fabricated device is tested using a custom made test PCB to allow for maximum testing flexibility with minimum required external equipment. The results of the testing are analyzed and ideas for future enhancements to the overall topology are given.