Digital Amplifier Module Integrated Switching Power Supply Design

Rapid development of Digital Audio Amplifier (DAA) in recent years mainly benefited from its inherent advantages compared that of Analog Audio Amplifier,such as cubage, weight, efficiency and robustness.Analog Audio Amplifier usually adopts traditional transformer power supply and AB Amplifier, so their low-efficiency, bulky and cumbersome lead great restrictions in many situations.This paper integrates Digital Audio Amplifier technology with switch-mode power supply technology, developed a high efficient and high power Digital Amplifier module. With its high power density, high performance, ease to secondary development, this module will be widely used in in many applications including Active speakers/Line arrays, Amplified mixers, low-cost professional amplifiers and multi-channel amplifiers, all of which never be achieved by Analog Amplifiers.This paper also briefly introduces the history, state-of-art, and future of Digital Audio Amplifier, and then describes the topological structure and principle of digital Amplifier as well as switch-mode power supply.This paper describes the whole design process of the module in details which include tradeoff-making on different schemes and key components, computation of parameters, structure design and thermal design. It also gives key performances of module as well as their measurement and result analysis based on the characteristics of digital amplifiers.This paper realizes a integrate module with a 2000 watt output, 1.3kg weight, 116 dB signal noise radio and 0.03% typical distortion. It also achieves an efficiency more than 80%.The module in this paper has reached the performances of high quality analog Amplifier. With only 1/3 cubage and weight of the same power Analog Audio Amplifier, it has a same level with the similar foreign products, thus it has prospective application in market.