The Design Of A Audioout System Based On Sigma-Delta Modulation

In this paper, we’ve designed a audioout system based on sigma-delta modulation. Putting forward the design process from digital to analog and gave the simulation result of the final circuit. All the design is based on aΣ-Δ(sigma-delta) modulation.The digital part which includes digital low pass filter design andΣ-Δmodulation is decribed in this paper. The analog part mainly include a low pass filter and an output power amplifier with there reference circuits and bias circuits and the realization of layout.This paper emphasis the design of analog circuits, advanced a realization of the analog filter through shift registers, resistor net and output power amplifier which is using the shift registers to complete the unit clock delay function, the resistor net to realize the coefficients of the filter and the power amplifier to play the role of adder. Firstly gave the theoretic structure. Secondly, gave the real circuits and simulation in spice model to validate the design and then draw the layout to complete the front design for the tape-out.The tape-out result prove the all design and result of the simulation, giving the guarantee of the industrial production.