Prof. D. Zhou UT Dallas. Analog Circuits Design Automation 1

Transcription

1 Prof. D. Zhou UT Dallas Analog Circuits Design Automation 1

2 General description Design automation of analog circuits has been an active research area in the past few decades. Conventional analog circuit design relies heavily on designer s experience and usually takes a long design period. As VLSI technology moves into nanometer scale and system performance requirement challenges every design aspects, it is necessary to automate design process with the consideration of process/operation variations. Analog Circuits Design Automation 2

3 General description Design automation of analog circuits has been an active research area in the past few decades. Conventional analog circuit design relies heavily on designer s experience and usually takes a long design period. As VLSI technology moves into nanometer scale and system performance requirement challenges every design aspects, it is necessary to automate design process with the consideration of process/operation variations. Analog Circuits Design Automation 3

4 Using the existing network and computing power, automated design will make such traditional laborintensive process into a machine-intensive one. Analog Circuits Design Automation 4

5 This class presents the recent advance in analog circuit design automation and includes following specific topics Modeling of analog circuit; Process variation and its impact on analog circuit; Efficient algorithms for the evaluation of analog circuit performance bounds; Circuits and systems performance optimization; Yield optimization with respect to process variation. Analog Circuits Design Automation 5

6 The class also includes a practical design project using state-of-the-art VLSI process to design a highperformance operational amplifier. Analog Circuits Design Automation 6

7 Introduction Importance of analog IC design 20% analog may demand 80% of total design time Analog Circuits Design Automation 7

8 Design flow Specification Performance requirement Manufacture technology Operation condition Choose circuit topology From the existing ones Most real design cases Only a few options Develop new one Performance/yield optimization Circuit and system operation conditions Determine circuit parameters Analog Circuits Design Automation 8

9 Simulation Spice Verilog-AMS Behavior model level Layout By layout engineers Based on experience Verification Simulation Need to include layout parasitic, such as capacitance, resistance and inductance introduced by the payout components Consider process variations Include noise and etc. Analog Circuits Design Automation 9

10 An OpAmp example Z.Yan, P.Mak, M.Law, R.P.Martins, "A mm^2 144µW Three-Stage Amplifier Capable of Driving 1-to-15 nf Capacitive Load With> 0.95-MHz GBW,"IEEE Journal of Solid-State Circuits, vol.48, no.2, pp.527,540, Feb Analog Circuits Design Automation 10

11 Performance Concerned: minimize current consumption Parameter Space: device dimensions Constraints: design specifications Analog Circuits Design Automation 11

12 In this example Topology has been fixed Need to choose manufacture process Need to determine circuit/system operation condition Need to optimize the performance Current consumption Satisfy the given conditions Analog Circuits Design Automation 12

13 Homework Read the reference Z.Yan, P.Mak, M.Law, R.P.Martins, "A mm^2 144µW Three-Stage Amplifier Capable of Driving 1-to-15 nf Capacitive Load With> 0.95-MHz GBW,"IEEE Journal of Solid-State Circuits, vol.48, no.2, pp.527,540, Feb Run SPICE simulation of the example At this point, do not worry about the performance and just get the SPICE simulation running Try to obtain the specified criterial Pay attention to how to determine the initial conditions which can make the simulation running. Due: Jan. 29, 2015 Analog Circuits Design Automation 13

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