Printed Circuit Board Reverse Engineering Practice
We will normally create single-sided boards through Printed circuit board Reverse Engineering, unless a design is so
complex that it requires routes on both side. Therefore, all parts should be moved from the top layer to the bottom. This can be done easily using the global feature. Double-Click a footprint to get to its properties, and change the Layer to Bottom Layer. Click the Global Tab, and then hit OK. All the Components should change from a bright yellow outline to a dark tan.
We can now actually reverse engineering the PCB.
We can first layout the components. Clicking a footprint and dragging the mouse will allow you to move the component. Pressing the Space Bar while doing this causes it to rotate. You should try to place the components reasonably close together (save surface area), and in a manner that ensures that the connections cross each other as little as possible.
This will make it easier for Protel to route the design. For this design, you can use the figure on the next page as a reference. We now need to define the dimensions of printed circuit board. This can be done by drawing a box around the components in the Keepout Layer from Printed Circuit Board Reverse Engineering. In the lower left of the screen there is a pull-down box that selects the currently layer you are working in.
Ensure this is set to KeepoutLayer. Then use Place/Line to draw the box. We now need to tell Protel’s AutoRouter to work only in the Top Layer. This can be done through Design/Rules. Select Routing/Routing Layers, click Properties, and set Bottom Layer to Not Used. We also should select Routing/Width Constraint, and change the parameters from 10mils to 15mils.
This will cause the Router to create electrical traces .015” wide. This should be a minimum. Traces always benefit from being wider, especially Power Signals. If a high amount of current goes through a thin trace, it will blow. Therefore, If it looks like your board can fit larger traces, increase the width constraint. Now select AutoRoute/All, and hit Route All. The Board should Route, with the result being similar to the figure below PCB Reverse Engineering.