Audio Digital Amplifier A Bit Excitation Signal Dsp Implementation

With rapid development of electronic technology and digital signal processing technology, audio power amplifier has come into a new era. Digital power amplifier has replaced the stage of the analog power amplifier, and technologies about it have been developing continuously. Compared with analog power amplifier, digital amplifier has many advantages, such as Hi-Fi, high efficiency, good match between amplifier and loudhailer, easy update, convenient debugging and so on. And it can process not only digital audio signal but also analog signal. Accordingly, it faces a vast market.In this thesis, how to design the 1-bit amplifier is introduced, and the main task is to achieve the pumping signal using DSP. This amplifier is mainly applied in these places, just as multimedia classroom, meeting-place and so on, where voice signal is amplified mainly and Hi-Fi is not needed mainly. It is a low-cost scheme. In the design, new research and technology are learned about, two modulation ways, PWM and Sigma-Delta, which can be used to develop digital amplifiers are compared, and theories about 1-bit technology are studied. Then, according to the simulation by MATLAB, factors which influence system function and parameters which control the work of parts are discussed. In the implementation, main task is to produce the pumping signal. And the way to switch level and design analog low-pass filter are put forward in the design, too.Plan using DSP is adopted in the design of the system. DSP chips produced by TI are suitable for the 1-bit system design. They can achieve two important parts of the system, interpolator and modulator, and finish the input and output of signals. In the developing, the software structure is finished by CCS, which can help us observe how DSP works. Based on the analysis of the first-order modulator and the structure of the second-order modulator, second-order modulator is achieved in MATLAB and DSP, which improves the ability of the noise-shaping.This thesis discusses relevant theories, provides algorithm simulation and how to realize the system, then sums up the points that are worthy of noticing and proposes some suggestions for the later part of the project.