Research And Design Of The CMOS High Precision Amplifier And Filter Circuit

The increasing requirement to hardware, especially, to semiconductor integrated circuit chip is due to the appearance of various new electronic products with higher and higher performance. Operational amplifier which is a full and basic part of most analog system and mixer-signal processing system, is critical in the design good performance operational amplifier will enhance the properties of the system. Now, many researches focus on the high speed signal processing and low power dissipation, which are appropriate domains we can make breakout. Basing on the common operational amplifier circuit design method, we design a wide band, high precision and low offset operational amplifier and filter circuit, successfully.The main work has been finished in paper is below:1. According to the most recent research of relative field, the specifications of the CMOS operational amplifier are discussed. These specification include open loop gain,output swing, slew rate,noise, which are the criterions of the amplifier. Then, the architecture and function of amplifiers are analyzed, mainly basic differential pair, folded-cascade and telescopic operational amplifier. Thus is the start point of our design work.2. Taking into consideration of the technological requirements of high precision low offset amplifier, a two-stage high precision OPAMP with the bias circuit is designed. Especially, the folded cascade input stage, Class-AB output stage, bias circuit, frequency compensation and noise characteristic are analyzed in details. In addition, to get a true high precision circuit source, the special Band-gap source circuit is made, so the high precision of whole operational amplifier circuit is guaranteed.3. With the software from the Cadence Corporation and the Spectre model, we run the simulation and get the result of the high precision operational amplifier which shows that the open loop dc gain is 84dB, the -3dB bandwidth is 12kHz and slew...