The Design And Implementation Of Train Digital Power Amplifier Based On DM368

With the rapid increase of information content in the multimedia age, the information content of train communication will also be increased, thereby by that means, the rail transit puts forward higher requirements about the performance of train passengers broadcasting system. In recent years, with the rapid development of communication technology, train radio technology has been a great development.In order to meet people’s needs for a large number of high-quality audio information transmission in the multimedia age, this thesis designs a digital audio power amplifier based on Ethernet. It can not only transmit and process a large number of audio information efficiently, but also can make passenger compartment inside and outside or passenger compartment within the left and right sides playing different content at the same time. In addition, this design has realized the radio volume automatic adjustment by using RS485interface for communication with environmental noise acquisition unit installed inside and outside of the passenger compartments, ensuring that passengers can still hear the content of the broadcast clearly in noisy environment.This thesis introduces the general development situation of train passengers broadcasting system and related technology and basic knowledge of the power amplifier firstly, and then according to the performace requirements of train passengers broadcasting system at the present stage, this thesis proposes a design scheme based on TI’s DaVinci Digital Media Processor TMS320DM368, audio codec TLV320AIC23BPW, digital audio power amplifier TPA3118D2DAPR, and RS485bus. Whereafter, this thesis introduces the design and implementation of the main function modules in detail, including data memory, program memory, audio codec circuit, Ethernet interface circuit, digital power amplifier circuit, serial interface circuit, power supply module, reset circuit, etc. Afterwards, this thesis introduces the design and implementation of PCB, including the selection of stack, layout, routing, and the preparing work before processing, etc. Next, the thesis introduces the test work of function and performance as well as the practical application, and analyses the corresponding test results. Finally, the conclusion is given, and the future development direction is prospected.