Analog Schematic Creation

Create the analog schematic shown in figure 3 as follows:

1. start a new schematic sheet
   1. select the Session item off the palette menu
   2. select the Open Sheet item off the palette menu
   3. enter a design name in the Component Name field of the pop-up form
   4. select OK on the form
2. select the Analog Library palette by selecting the Libraries --> MGC Analog Libraries --> Display Libraries Palette from the menu bar.
3. Make the analog libraries palette the default palette. Enter the palette menu pop-up and choose Set Default Palette
4. Return to the schematic palette by entering the palette menu pop-up and choosing Display Schematic Palette
5. select the nmos transistor as follows:
   1. select the Choose Symbol item from the palette menu
   2. change to the analog parts library by selecting the change directory item in the pop-up. The change directory item is the one with arrows point up, right, down, and left.
   3. enter the analog parts library directory $MGC_APLIB and select ok on the form.
   4. select the nmosfet component. Note: You should use the NENH4 component from the Generic Parts item on the libraries palette, this component has an explicit connection for the bulk potential.
6. place the 6 nmos devices required
7. select the pmos transistor
   1. select the Choose Symbol item from the palette menu
   2. select the pmosfet component. Note: You should use the PENH4 component from the Generic Parts item on the libraries palette, this component has an explicit connection for the bulk potential.
8. place the 6 pmos devices required
9. flip one nmos and one pmos device
   1. unselect everything by pressing the F2 key
   2. select the nmos and pmos device to be flipped by placing the mouse cursor on the transistor and clicking the left mouse button.
   3. flip the devices using the edit window pop-up menu item Rotate/Flip --> Flip --> Horizontal
10. move the flipped objects back into position
    1. unselect everything with the F2 key
    2. select one of the flipped transistors by placing the mouse cursor on the transistor and clicking the left mouse button
    3. select the move item from the edit window pop-up menu
    4. move the outline of the transistor to the correct place
    5. click the left mouse button
    6. press the ESC key to remove the pop-up form.
11. add the instance (top) label to each transistor
    1. select all the transistors
    2. select the Properties --> Modify item from the edit window pop-up menu
    3. select the INST property from the pop-up form
    4. select the replace button on the Property Value item of the pop-up form
    5. enter any value for the property
    6. unselect everything by pressing the F2 key
    7. select the Text item from the palette menu
    8. select the Sequence Text item from the new palette menu
    9. enter p in the New Prefix field of the pop-up form
    10. enter 1 in the Beginning Index Number field of the pop-up form
    11. select the Manual button under the Sequence Type field of the pop-up form
    12. click the left mouse button on the added label on each pmos transistor
    13. click the right mouse button after all six pmos transistors are labeled
    14. do the same for the nmos transistors using n in the New Prefix field
12. change the model (middle) properties by selecting all the transistors that use the same model and using the Properties --> Modify entry of the edit window pop-up menu. This property is the one that selects the model to use for the transistor in the simulation. The property name to choose on the pop-up form is:
    • Select ASIM_MODEL for the four terminal devices and any other devices picked from the libraries palette, then Click OK.
    • After you have a pop-up window, type nch.x for n-mos, or type pch.x for p-mos in the Value field. Use the 1.8V Mos Devices Table to select the correct model name.
13. change the instpar (bottom) properties(Transistor Size) in the same manner. Select the INSTPAR and click OK, then type transistor size in the Value field. If a transitor size (W/L) = 5um/1.2um, then type W=5U L=1.2U. This property is the one that selects the sizing information for the transistors in the simulation. This property also selects the vlaues for resistors and capacitors.
14. add the ports
    1. select the analog libraries palette by selecting the Library item on the schematic palette
    2. select the Generic Parts entry of the palette menu
    3. select the portin component and place the input ports
    4. select the portout component and place the output port
15. add the capacitor by selecting the cap component on the palette menu
16. connect all the components
17. change the port names
18. check the design
19. close the check window
20. save the design by selecting the File --> Save Sheet item from the menu bar
21. print the design
    1. select the File --> Print Sheet item form the menu bar
    2. enter mentor_c211 in the printer name field
    3. select OK on the form
22. exit design architect by double clicking the bar on the window border
23. Create the necessary design viewpoint to simulate the design (this only needs to be done once on a design) by typing in the command :

    create_accusim_vpt -design <design_name> -model /tmp_mnt/class/EE571/models/log018.eldo53

    where <design_name> is the name you chose for the design. If you are not in the EE571 class then the file name after the -model in the command must be a file that you created.

 
Figure 3: Sample analog design