Reusable Design Of Low Voltage CMOS Operational Amplifier

The design of System on a chip (SoC) is mostly based on the deep sub-micronatpresent. In view of shortening the cycle of IC design, especially the design of digitalcircuit system, IP design reuse technology is broadly attached importance to anddeveloped, but the research and application of analog IP design reuse technology getsbehind for digital IP. It is urgent to research and develop analog IP reuse technology.With the popularizationof portable electronics at the same time, low voltage design hasbecometheessentialrequirementofcircuitsystemforworking.The paper is based on the project, research of analog IP design reuse andverification technology, which comes from Institute of Electronic CAD of XidianUniversity.Taking operational amplifier(op amp), the most basic and important cellin the analog integrated circuit, for research object, the paper makes an intensivestudy of the reusabilityandlowvoltagedesign ofop ampinthe design of SoC.Firstly,thepaperpresentstheimportanceofIPreuse designandlimitationofanalogIPindetail;secondly, based on requirement for the reuse design of low voltage CMOS op amp, thepaper separately discusses and presents the low voltage op amp design of circuit andlayout.TheICdesignoflowvoltageopamp isbasedontheTSMC0.6umCMOSprocess,andthepre-simulationoflowvoltage reusableop amphasbeen completedbyusingtheEDA tools, such as Cadence and Hspice. The results of simulation indicate thatperformance index of this op amp is good, operatingsupply voltage range is5~2.5V.Inthe typical model, open loop gain is 102dB, gain bandwidth is 6.25MHz, phase marginis 88.77o, PSRR is 80dB, CMRR is 72dB, so the low voltage op amp can be applied inmost digital-analog mixed circuitsand SoC.This design has been applied in the projectXDM02, and also it has been taped out. The result indicates low voltage op amp is ingoodworkingorder.