DC Circuit Simulation

Transcription

1 Chapter 2 DC Circuit Simulation 2.1 Starting the Project Manager 1. Select Project Manager from the Start All Program Cadence Release 16.5 Project Manager. 2. Select Allegro PCB Designer (Schematic) from the list. 2.2 Opening the Allegro PCB Designer 1. Click on the Create Design Project icon in the Project Manager window to display the New Project Wizard window. Figure 2.1: Create Design Project 7

2 8 CHAPTER 2. DC CIRCUIT SIMULATION 2. Enter lab1 in the Project name field. You can browse to the location you want to work or you you can enter the path. If you enter the path and the directories do not exist, the tool will create them. Please save your work to either a network drive or a USB storage device. The computers will be updated from time to time without advance notice from the system administrator. Click Next. Figure 2.2: Create Project Name and Location 3. Click on Add All. Click on the Next button when finished.

3 2.2. OPENING THE ALLEGRO PCB DESIGNER 9 Figure 2.3: Project Library 4. Select pspice_elem as the library. Enter voltage_divider as the Design Name. Figure 2.4: Design Name

4 10 CHAPTER 2. DC CIRCUIT SIMULATION 5. Click Next and Finish. 2.3 Design Entry 1. Click the Design Entry icon Figure 2.5: Design Entry 2. A window for the Allegro PCB Designer (similar to the one shown below) will appear next.

5 2.3. DESIGN ENTRY 11 Figure 2.6: PCB Designer 3. Select Component Add from the Allegro Design Entry Window. 4. Enter V* under the Cells Column. 5. Scroll and select vdc from the Cells column, and click the Add button to attach the voltage source to your cursor. You may have to use Zoom Fit to see the voltage source after it is added to the schematic.

6 12 CHAPTER 2. DC CIRCUIT SIMULATION Figure 2.7: Add a DC Voltage 6. Select Text Attributes, then left-click on the voltage source to open the Attributes window. 7. Edit $Loation value, changing it to V1, then click OK. Edit DC to 10VDC. Figure 2.8: Change attributes of a voltage source. 8. You will place resistors on the schematic next. 9. In the Component Browser window, enter r* under the Cells column. Left-click to place the resistors. You can left-click another location, right-click and select Rotate from the pop-up menu to change the orientation of the resistor.

7 2.3. DESIGN ENTRY You can right-click, select move to move a resistor. 11. Use Text attributes to name one resistor as R1 with a resistance of 1k Ω and the other resistor as R2 with a resistance of 2k Ω. Figure 2.9: Place parts on a schematic. 12. Select Wire to Draw to begin wiring parts. Press the Esc key when you are done wiring. 13. Open the component browser (Component to Add), enter 0* from the Cells column to add a ground to the schematic. 14. Connect the ground to the schematic as shown below. 15. Select Wire to Signal Name to display the Signal Name window. 16. Select the Queue option. In the Signal Name window, enter Vin, press <return>, entervout, andpress<retrun>. 17. Referring to the schematic. Place Vin on the segment of the wire between V1 and R1. Place Vout on the segment of the wire between R1 and R2.

8 14 CHAPTER 2. DC CIRCUIT SIMULATION Figure 2.10: Place Signal Name 18. Close the Signal Name window. 19. Select File to Save to save. 20. Here is the final schematic. Figure 2.11: Final Schematic 2.4 Setting Up a DC Simulation 1. Select AMS Simulator from the pull-down menu. Select Enable PSpice Simulation. 2. Click OK to use this design for simulation flow. 3. Select AMS Simulator from the pull-down menu. Select New Simulation Profile.

9 2.4. SETTING UP A DC SIMULATION Provide a name for the new simulation profile, e.g. voltage_divider_dc_sim. 5. Click on Create. 6. Select Bias Point as the Analysis type. Figure 2.12: DC Analysis 7. Start the simulation by choosing AMS Simulator Run. 8. Click on View Output File to see the spice file generated. 9. Choose AMS Simulator Bias Points Enable to display bias voltage on the schematic. 10. Select Enable Bias Voltage Display under AMS Simulator Enable.

10 16 CHAPTER 2. DC CIRCUIT SIMULATION Figure 2.13: Annotated DC results 11. Plot the schematic with voltage annotated at each node. Select File plot setup to specify how the scematic will be printed. Choose Fit To Page option if the schematic is too small. Figure 2.14: Plot setup