Research On High Speed And Broadband Video Operational Amplifier With Sampling And Holding

In recent years,with the rapid development of electronic systems,we have made a tremendous progress in the field of analog integrated circuits.The market share is also gradually increasing.The gap between us and other companies,such as ADI,TI,is becoming smaller.That is why the United States imposed sanctions on ZTE in 2018.With the outbreak of this incident,we realize that in these high-tech core device fields,which represent the strength of science and technology,so far,The United States still occupies a dominant position and holds the lifeblood of the entire semiconductor development.In order to better develop independent core chips and no longer be controlled by other American companies,we should put efforts to promote the process of full localization,autonomous and controllable from circuit design to chip production.In order to solve the above problems,this paper takes DC restoration in the subdivision field of video system application as the main research object.On the basis of analyzing the technical principles of high-speed broadband video operational amplifier and sample-and-hold amplifier,a circuit scheme based on domestic independent process design is proposed,which is finally verified by simulation.In order to achieve high-speed and broadband performance,the main operational amplifier designed in this paper will use current-feedback structure.The current-feedback operational amplifier is compared with the voltage-feedback operational amplifier,and the advantages of using current-feedback operational amplifier are proposed.Then we will analyze and design the sample-and-hold amplifier,and propose the typical structure of the sample-and-hold circuit.Finally,by designing appropriate bias and start-up circuits,we connect it with the main operational amplifier and the sample-and-hold amplifier,then use a sampling capacitance in the periphery,we build a complete DC restoration system and analyze its working principle.We will use EDA(Electronic Design Automation)tools to simulate the single circuit and the total circuit,then compare the results with our design expectations.In addition,in order to achieve the goal of localization from designing to taping out,we plan to design and simulate based on an autonomous and controllable process routine in China.The process is a standard high-speed complementary bipolar process,which provides a complete set of devices and simulation models with high frequency,and can meet our design targets.Using the standard device library provided by the process,we design the layout of the circuit,follow the process design rules,and in order to reduce the parasitic effect of the circuit,we fully consider the symmetry and reliability design in the layout of the device,and finally design the layout of the circuit.The circuit is powered by ±5V dual power supply.It can achieve 300 MHz 3dB bandwidth and 1500V/?s slew rate.It is mainly used in common video signal processing systems such as SVGA and NTSC.