In this tutorial, we will learn how to make footprint in ARES whose PCB package is not present in the library. We will go through step by step process of making footprints in Proteus ARES and will learn how to assign the footprint to an ISIS symbol.
Tutorial: Step by step process to make footprint in ARES Proteus
Proteus in widely used by design engineers and students to verify their simulations and make PCB (Printed circuit Board). Proteus has two sections. One is ISIS which is used to design and simulate electronic circuits. The second section is ARES which is used for the designing of PCBs. A printed circuit board (PCB) is the board base for physically supporting and wiring the surface-mounted and socketed components in most electronics. Ares has a rich library which contains PCB footprints of many ICs and components however there are some electronic components whose footprints are not present in ARES. It is still possible to use such components in PCB to make circuit. It is because ARES provides the facility of creating custom footprints and using them in PCBs. So this article deals with the step by step process to make footprints in ARES Proteus.
Step 1: Selection of type of Package.
The first step of making ARES package is to find the type of footprint. Generally there are two main types of packages
- DIL (Dual in line) or also called DIP (Dual in line package): It is through hole technology in which the method of fitting components on PCB is inserting leads into the holes on PCB and soldering them.
- SMT (Surface mounted technology) or also called SMD (Surface mounted device): In this technology the components are mounted and soldered on the surface of PCB without making holes into it.
This information can be found in the data sheet of that component. From the datasheet of LM301, we found that it has DIP package.
STEP 2 Finding dimensions:
The next step is to find the dimensions of the component. From data sheet of LM301 all the dimensions can be acquired. The pages of datasheet which displays the dimensions are shown in the following figure.
Although all dimensions are important however, size of pin, horizontal and vertical distance between the pins is critical. Any mistake in them can lead to a situation where the device would not fit on its designated space. All these critical dimensions can be seen from the above figure.
STEP 3: Setting in ARES.
The first thing to do in ARES is to select a measuring system. Two types of measuring systems are available. One is metric system whose units are meters, centimeters and millimeters. The second system is imperial which measure length in terms of inches and feet. The choice of selecting particular system for making footprints depends upon the units used in component’s datasheet. It can be done as shown in the figure.
After selecting the units, next stride is to set the scale. Scale is the dimension of smallest square. It is recommended to select the smallest as possible. In ARES the smallest is 1th. Th stands for thou which 0.001 of 1 inch. It can be called as 1 milli inch. It can be selected as follows
Step 4: Making body or edges of component
According to the size of component, make a 2D box of the same dimension. It can be drawn by selecting 2D graphics line mode from the left menu. It is recommended to start the border (box) from the origin of the page for the sake of convenience. Origin is indicated by blue circle. In case of LM301, the box size is 0.4 x 0.220 (inches)
When the borders are made, change the layer of the box to the border edge. It can be done by right click on the box and going to the change layer as shown in the following figure. The color of border will turn yellow when the board edge layer is selected.
Step 5: Pin Pads
Next step is the placement of pin pads on body or edges. There are three types of pin pads available for the DIP style of footprint. They are round, square and DIL pad mode. According to the shape of the pins, the style of pin pads is to be selected. I recommend the DIL oval shaped pads. The size of the pads should also be according to the width of pins.So select a pin pad put it on the edge of board according to the distance given in its datasheet. For LM301 the distance of first pin pad from board edge is 0.055 inches in X direction and 0.8 in Y direction. Place the first pad correctly as shown in the figure.
Step 6 Replicate Pin Pads.
Now replicate pin pads in X direction first. The dimension required from the datasheet for this step is the center to center distance between two pin in horizontal direction. In the given case it is 0.100 inches.To perform replication, select the pin pad, right click and select replicate. Specify the number of replicates and distance between two pins. In this case, the number of duplicates is 3 and distance between connective pads in horizontal direction is 0.100 inch which is specified in the Replicate window.
After replicating the pads, the footprint will look like.
Now with the same method, replicate the pads in the Y direction. And then again in X direction to complete all 8 pins. The package will is shown in the figure.
Step 7 Numbering the Pads
Number all the pads according to pin numbers in the data sheet. To do this, double click on each pad and enter number in specified space.
STEP 8 Making Package
After naming the pads, make the package and specify its name, type and category of the newly created footprint. To accomplish this task, select whole component, right click and go to make package as shown in next figure.
The following window will appear where the required information should be entered.
Mostly this is considered the end of the process to make footprint in ARES however one important step is still left.
Step 9 Assigning Footprint to ISIS symbol.
Last step to make footprint in ARES is to assign it to any ISIS component or newly created ISIS symbol. To learn how to create your own symbol please refer to my article create own ISIS Symbol. Go to ISIS, select the ISIS symbol, right click and go to packaging tool. Click next and click on add/edit the following screen will appear. It shows pin number and names.
Click on add to select footprint from ARES library. Write name of user package which was created earlier. It was named LM301. So write lm301 and it should appear. Select it and click ok.
Make sure pins are assigned correctly. Select default package and click on assign package.
Click next and follow the instructions.
If you have any question regarding the process and steps to make footprint in ARES please ask in Comments. Also share it with your friends if you like it.