Cadence Schematic Tutorial - University Of Florida
Cadence Schematic Tutorial EEE5320/EEE4306 Fall 2015 University of Florida ECE 1
Remote access You may access the Linux server directly from the NEB Computer Lab using your GatorLink username and password. If you would like to access the Linux servers from your own computer or off-campus, you may refer to the ‘Accessing Linux Servers Remotely’ tutorial in order to set up a remote connection 2
Run Cadence and create a new library On the linux terminal, type the italicized commands below - source /apps/settings : source cadence settings - icfb & : Run cadence Click File New Library on the Library Manager menu to make a new library Click Attach to existing tech library on the new pop-up window, choose TSMC 0.24u CMOS025/DEEP (5M, HV FET) and click OK. 3
Create a new schematic Click your library on the library manager. Click File New Cell View on the library manager. On the new pop-up window, choose Composer-Schematic for a new schematic (or Virtuoso for a new layout). You will see a blank schematic window. 4
Run ADE and choose a simulator On the schematic menu, click Tools Analog Environment. In the Analog Design Environment (ADE) window, click Setup Simulator/Directory/Host. Choose spectre as your simulator. 5
Add tsmc 0.25um model file You can download the tsmc 0.25um model file from www.mosis.org or googling. On ADE, click Setup Model Libraries. On the new window, click Browse, and choose the model file you downloaded. Then click Add in the bottom left of the Model Library Setup window Now you are ready to use the tsmc 0.25um process. 6
Draw a circuit Click instance on the left side of the schematic window to add resistors, caps or TRs. On the component browser, the two commonly used libraries are NCSU Analog Parts and analogLib. You can find NMOS in NCSU Analog Parts N Transistors and PMOS in P Transistors. Choose nmos4 and pmos4. You can find voltage and current sources, resistors, caps and so on in analogLib. You have to make sure that the names of the pmos and nmos should be matched to the names of the model file you have. - tsmc25dP and tsmc25dN in this instruction. 7
Draw a circuit (continued) You can find the voltage sources in analogLib Sources Independent. Use vdc for V0 and vpulse for V1 in the figure below When placing each instance you can set the parameters in the Add Instance window. Otherwise you can add the part to the schematic, select the component, and click Property in the toolbar on the left side of the Schematic Editor Enter the parameters for V1 (vpulse) as shown in the figure on the left Set the remaining parameters for V0, P0, and N0 as shown in the figure on the right 8
Run transient simulations In the ADE window click Analyses Choose tran or click Choose Analysis on the right side. Enter a Stop Time and check Enabled. Click OK. Click Simulation Netlist and Run or click Netlist and Run on the right side of the ADE window. You MUST SAVE your schematic every time you run a simulation, otherwise the last saved schematic will be simulated. 9
Plot transient outputs On ADE, choose Session Options Waveform Tool Wavescan or AWD depending on your preference. You will see different plot settings. After running a tran simulation, click Results Direct Plot Transient Signal, and then choose the voltage node on the schematic that you want to plot. Press ESC on your keyboard to plot. To plot the transient current you should first save the current by clicking, on ADE, Options To Be Saved Select On Schematic, and then choose the current you want to save (To choose a current, select the node at which you want to measure the current). Then, run a tran simulation, and plot the current. You can also use the calculator. You can do almost every function using the calculator. For example if you want average current of the inverter, run the calculator by Tools Calculator on ADE. Click it on the calculator for transient current, on your schematic click the current flowing through Vdd. On your calculator, click Special Functions average, click plot or check Evaluate Buffer on the calculator to plot or calculate, respectively. 10
Run DC simulation Apply a proper DC voltage input that every transistor is working on its saturation region. In the ADE, select Analyses Choose dc. Check Save DC Operating Point, Enabled, and then OK. Uncheck Enabled under tran. Run a simulation (Simulation Netlist and Run). In order to see the node voltage or DC operating point, in ADE choose Results Annotate DC Node Voltages or DC Operating Points, respectively. – To return to the original schematic annotation, in ADE choose Results Annotate Design Defaults In order to see the detailed operating point of a transistor, in ADE choose Results Print DC Operating Points, and select the specific transistor 11
Run AC simulation Apply a proper DC voltage input to the inverter. Add an AC voltage of 1 V on the voltage source. Click Analyses Choose ac, put a specific frequency range, check Enabled, and run. To plot the gain of the inverter, click on ADE Results Direct Plot Main Form. On the new window, choose ac and dB20, choose the output node on the schematic to plot the AC response. 12
Make a symbol Define inputs (vdd, vin, and gnd) and outputs (vout) using pins. – – Remove/Delete the voltage sources (V0 and V1) and gnd terminal Select Pin on the left side of the Schematic Editor – Enter the Pin Name and Direction then place the pin in the schematic window – To place multiple pins with the same direction: Enter each pin name separated by a space Set Placement to Multiple Then place the pins on the schematic in the order they appear under Pin Names 13
Make a symbol (continued) On the schematic, click Design Create Cellview From Cellview. Click OK on the new window, then you will have a symbol with a rectangular block. Modify the block depending on your preference. Make sure the pin names of the schematic and the symbol are matched. On the symbol window, click Edit Origin, and then click the input pin for origin. To use the symbol you made, click instance on a schematic window, choose the library in which the inverter is located, and choose the symbol you just made. Then put it on the schematic. 14
Save and load ADE setting To save the ADE settings, click on ADE Session Save State. On the new window check Cellview, check settings that you want to save on What to save. Click OK. To use the setting that you saved, click on ADE Session Load State. On the new window check Cellview and click OK. Make sure your simulator is spectre before loading the state (Refer to Slide 5). 15
Useful hotkeys On the schematic i : instance w : wire l : wire name label p : add pin q : Property c : copy m : Move r : rotate s : stretch f : fit to screen shift z : zoom out ctrl z: zoom in f8: check and save L : Add note x : go into the inside of a symbol for read only. shift x : go into the inside of a symbol for edit. b : Return to upper level of symbols. Ctrl r : redraw/refresh schematic view On the plots a : marker A b : marker B d : delta markers 16
Useful default instances location NMOS PMOS Resistor, Capacitor, and Inductance Vdd, gnd Volt and current sources VCCS, VCVS, CCCS and CCVS NCSU Analog Parts N Transistors nmos4 NCSU Analog Parts P Transistors pmos4 analogLib Passives analogLib Globals analogLib Sources Independent analogLib Sources Dependent 17
Make sure the pin names of the schematic and the symbol are matched. On the symbol window, click Edit Origin, and then click the input pin for origin. To use the symbol you made, click instance on a schematic window, choose the library in which the inverter is located, and choose the symbol you just made. Then put it on the schematic. 14
Cadence Design Systems provides tools for different design styles. In this tutorial you will learn to use three Cadence products: Composer Symbol, Composer Schematic and the Virtuoso Layout Editor. This tutorial will help you to get started with Cadence and successfully
UW ASIC DESIGN TEAM: Cadence Tutorial Description: Part I: Layout & DRC of a CMOS inverter. Part II: Extraction & LVS of a CMOS inverter. Part III: Post-Layout Simulation. The Cadence IC design flow is depicted below. In the first Cadence tutorial we covered the “Schematic Captu
2. Cadence has many keyboard shortcuts. When the tutorial writes a letter of a command in parentheses it means that letter is the short cut. Capitalization is significant. For example i is the shortcut for (i)nstantiate. Getting Help within Cadence Here are two ways to get help within the Cadence environment. 1. Click on Help within a Cadence .
CADENCE SETUP This short tutorial shows how to configure Cadence to use the NCSU Cadence Design Kit (CDK) with access to the ON Semiconductor C5 0.5-µm and the TSMC 0.35-µm CMOS processes libraries. In LINUX Right button of mouse - Open Terminal Make cadence directory ece.gatech.edu mkdir ca
EMIL Tutorial Series Tutorial #1 Basic Analog Simulation in Cadence In this tutorial we step through how to start Cadence (or at least a very basic version of it), how to define a library linked to an appropriate technology file, how to build a schematic and then how to simulate it with Spectre. 1 Sta
The next section describes the basics of the schematic capture tool in Virtuoso used to prepare a circuit for simulation. Part 3: Schematic Capture To practice schematic capture, we will create the circuit shown in the Pre-lab section. You should already have the schematic editor window open editing the schematic view of the cell lab1.
So, you have a running cadence at the moment. Remember that, the previous steps are for initializing the cadence for the first time, and they should be done once only. Now close cadence by File Exit. 1.2.2. Running Cadence You have initialized cadence in the previous part. After the first run, you need to do
Cadence Virtuoso Logic Gates Tutorial rev: 2013 p. 4 . New Cell windows . Virtuoso Schematic Editing window . Add Components: With the 2x1AND cell schematic generated, you can now begin to design the AND gate using components in the ECE331 library. 6. In the Schematic Editing window, select Cr
