ECEN 1400 - Introduction to Digital and Analog Electronics

Peter Mathys, Spring 2014


Create LM386 Component in Multisim

The LM386 is a low voltage audio power amplifier integrated circuit (IC). To be able to simulate the component in Multisim and use it in Ultiboard PCB designs, it needs to be created using the Component Wizard in Multisim. Files needed: Symbol file (LM386.sym) and SPICE model (LM386.cir).

Start Multisim. Under "Tools", choose "Component Wizard".

Step 1: Enter component information.

Component Wizard - Step 1 of 8

Step 2: Enter footprint information.

Component Wizard - Step 2 of 8

Click on "Select a footprint".

Select a footprint

There are some 5000 footprints in the Master Database. To find the one that we need more easily, click on "Filter". Click on "Add row" and select "Footprint" from the drop down menu under "Column". Set the "Operator" to "Contains" and enter "DIP8" under "Value" as shown below.

Filter

Select the "Ultiboard DIP8" footprint.

Select Ultiboard DIP8 footprint

Click on "Select". In the footprint information window set the number of pins to 8.

Component Wizard - Step 2 of 8 with footprint info entered

Step 3: Enter symbol information.

Component Wizard - Step 3 of 8

Click on "Edit" to open the Symbol Editor.

Symbol Editor

Download the file LM386.sym and remember the location where you put it. In the Symbol Editor click on "File" and "Open..." and open the LM386.sym file.

LM386.sym in Symbol Editor

Do not change any of the pin information that appears at the bottom of the symbol editor. Click on "Exit" and answer "Yes" to the "Save changes?" question. Now the symbol information window should look like this:

Component Wizard - Step 3 of 8 with LM 386 symbol information

Step 4: Set pin parameters. Click on "Next" and change the pin Types for the different pins (from "BIDIRECTIONAL") to the values shown below.

Component Wizard - Step 4 of 8 with pin Type filled in

Step 5: Set mapping information between symbol and layout footprint. Click "Next" and fill in the footprint pins in as shown next.

Component Wizard - Step 5 of 8 with mapping between symbol and footprint

Step 6: Select simulation model. Click "Next" to obtain the "Select simulation model" window.

Component Wizard - Step 6 of 8

Download the file LM386.cir and remember the location where you put it. Then click on "Load from file" and open the LM386.cir file. You should see a window with the LM386 SPICE model filled in as shown below.

Component Wizard - Step 6 of 8 with LM386 SPICE model filled in

Step 7: Mapping information between symbol and simulation model. Click "Next" and fill in the Model nodes in the Pin mapping table as follows. (Note: The model nodes are numbered 1,2,3,... from left to right in the .SUBCKT specification, irrespective of the pin numbers in the footprint mapping.)

Component Wizard - Step 7 of 8 with Model nodes entered in Pin mapping table

Step 8: Save component to database. Click "Next" and in the next window click on "User Database" and select "Analog".

Component Wizard - Step 8 of 8 with User Database Family tree

Click on "Add family" and enter "Amplifier" for the family name.

Component Wizard - Step 8 of 8, New Family Name

Finally, click "Finish" and you are done with LM386 component creation. Check that you can select the component in Multisim.

Select LM386 component from User Database in Multisim

Then place the component on a schematic.

Place LM386 component on schematic