Micro-circuit Design Used In The System Of Neural Signal Recording And Stimulating

In recent years,neural signal recording is one of pop problems in the territory of life sciences research. Neural microelectrode is a sensor system which can communicate with the nerve system of organism. Going with swift development of integrate circuit and micro elecro-mechanical system (MEMS), neural microelectrode has developed to the level of multidimensional active microelectrode array which integrates a number of signal process circuit. Correspond to it, design of the needed recording circuit also faces to austere challenge. Power waste,size,noise and integration degree are the chiefly problems that need to be taken into account.The micro-circuit of this study is mostly composed of preamplifier and address encoder, which belongs to digital-analog mix integrated circuit. It achieves by CMOS technics which has advantage of high integration degree and low power waste. The objective of this study is to design and to improve on the micro-circuit which will be microassambled with passive electrodes to compose 3-dimension active neural microelectrode array, use it in clinic which makes it feasible to cure the diseases in matter of nerve center system.This paper simulates the former circuit by HSPICE and tests the CMOS chip, that based on the in-depth study on circuit structure and function principle of the former micro-circuit. Disadvantages consisted in the former circuit are founded by simulation and testing, improvement project is presented, improvement of circuit structure and ascertainment of design guideline are accomplished. Aiming at the requirements to preamplifier in voltage and power waste aspects and so forth, new transistor parameters are obtained through calculation, which theoretically satisfy the design guideline on the whole. Based on Charted 0.35um technology model and HSPICE simulator, particular improved circuit simulation is carried out. Optimizing design of improved circuit is completed based on simulation result. The simulation result indicate that the disadvantages consisted in the former circuit are settled by improved circuit, which achieve anticipative design guideline requirement. Finally, combining with especial requirement of circuit, on the condition of considering match,parasitic and reliability, the improved circuit layout design is finished and DRC,LVS verification are succeeded.