|
Integrated circuit design , Sigma-Delta modulator is widely used in the field of high-precision analog to digital conversion . Since this circuit structure and work characteristics, the present special difficulties simulation , circuit simulation techniques generally difficult to meet the requirements of high accuracy and high efficiency . In order to obtain the modulator performance parameters, such as SNR , simulation of thousands or even more need to traverse the sampling period of the complex structure of the modulator , it takes several hours or even days . Simulation is the primary means of integrated circuit design , these difficulties to the design of high-performance Sigma-Delta converter is a big problem . This article is a Sigma-Delta modulator efficient simulation technology. First, a brief introduction Sigma-Delta converter structure and working principle , an overview of the most commonly used Sigma-Delta modulator simulation technology . Common Sigma-Delta modulator of the simulation is divided into three levels: a high level of behavioral simulation , simulation of the equivalent circuit of the intermediate level and the bottom level of the transistor -level simulation , the paper describes the simulation of the basic principles of the levels , according to the characteristics of the respective a comparative analysis . Equivalent circuit level simulation in accuracy, speed to get a better balance between , the paper 's main job is in the equivalent circuit -level simulation, presents a sample data considering nonlinear effects simulation algorithm , linear sampling based on data analysis algorithms , considering the waveform iterative non-linear element , making the accuracy of the simulation results with the significant improvement achieved with a smaller computational cost , the purpose to obtain a higher accuracy . Details of the algorithm, including the description of the circuit , iterative process , and using numerical Laplace inverse transform method for solving linear circuits . With the above method, the type of circuit simulation. Including continuous Sigma-Delta Debugger , switched capacitor integrator and switched-capacitor Sigma-Delta modulator. The experimental numerical and graphical results while , and common SPICE simulation tools were compared , these examples demonstrate the effectiveness of the method .
|