The Design And Study Of Active Filter Based On The Amplifier Operator In The Circuit

Since entering 21st century, microelectronic technique and computer technology have gotten development at high speed.Meanwhile,with the progress of very large scale integration technology and urgent demand of the integrated trend of electronic system,the analog integrated circuit design method receives the extensive attention day by day.At present,The low voltage and low power CMOS analog integrated circuit and the current mode circuit with a great deal of merits are concerned very much by theory researchers and project engineers for VLSI technology.The paper studies the theoretics and application of Opertational Transconductance Amplifier (OTA) and filter circuits,narrates the present state of the research of analogy integrated circuit at home and abroad.The model of MOS transistor and several kinds of basic integrated circuit uinit module formed by MOS transistor are then introduced.The simulation circuits of active network elements and analog signal operation based on OTA are induced systematically.On the basis of summing up some methods to design second-order filters,a kind of fully differential continuous times CMOS OTA-C biquad filter is proposed.At last the design method of continous time high frequency analog integrated OTA-C filter is introduced in detail,several circuit instances are proposed and simulated with the Pspice programs,and the simulated results are satisfying.At the same time ,a novel digital-to-analog converter(DAC) of OTA topologies is presents.