With 10 mils trace and space you can have pads with up to 70 mils in diameter. Through hole pads can also be trimmed to be more rectangular and sometimes with the holes off center, just to increase the spacing between the pads. Long and narrow copper areas that are not connected in both ends can also come loose and cause problems. The continue to do that for the rest of the board. Move that via up a bit and perhaps also the via between the 0603s and then repour. The second pair of 0603s has a via that breaks the surrounding polygon.
Look at the top row of components on the featured layout. Sometimes it is also worth the penalty of added vias to change the routing layer for a few segments just to keep the polygons more intact. Do a rough layout and then move traces and vias, repour and try to get connections between polygons of the same net. Try to keep all polygons as intact as possible instead of just stitching with a single via. Posted by DP JJPosted in Eagle Tags: Eagle Polygons Post navigation Multiple supply polygons, good for power distribution especially on CPLD and FPGA chips.Īlthough a normal traces can be used here, concentric C shaped polygons provide both a power supply access, and give you more freedom with it’s shape. Power distribution for multiple voltage powered chip We use these for fat power traces where the board will carry a lot of current. Power planes are no different than ground planes, they just carry a power supply instead of ground. Click the ratnest button to refresh the ratnest after adding parts or tracesĪny parts placed in the ground plane with pins names GND will automatically connect.Give it the same name as the ground connections on your schematic, usually ”GND”.It can also reduce electrical noise on the board.įilling the board with a ground plane is the first thing we do when designing a PCB. The ground plane connects all the ground pins on a PCB automatically, which usually makes routing easier. Ground planes fill-up the empty spaces of a PCB with copper connected to ground. We only turn it off on high power traces that require more conductivity between the pad and the polygon. Thermals make soldering easier, the part heats faster because the heat is not dissipated as quickly.ĭisable thermals will make a solid pour trough the pin/pad. With thermals on, a pin will connect to the polygon through small traces extending from the pin center in 4 directions. When using a ground fill over the entire board it is important for it to have the highest rank so other polygons can be drawn. Rank determines if one polygons if above or below an overlapping polygon.Īssigning a lower rank to one polygon will make that polygon dominate the other as seen in the pic above. Low isolation values lead to PCBs with electrical faults from under-etching. This is the clearance between the polygon and neighboring objects, such as other traces, pins, and other polygons.ĭon’t torture your board house here. We only use the solid fill option in our projects. Line spacing is adjusted in the ”Mesh Distances” property. Hatched line widths are adjusted in the ”width” property. Here you can select between two versions of fill for inside the polygon, solid or hatched. This is the width of the polygon’s perimeter when you draw it on the board. This opens the ”Polygon properties” menu. Right click on the edge of a polygon and select properties. Here make sure ‘This Polygon’ is selected, and type in the net name you want it to connect to. To connect the polygon to the ‘net’ you want, right click on it’s edge, and select ‘Name’. For example if you wanted to beef up a power trace. Sometimes it’s useful to make the polygon part of an existing trace or electrical net. Next we’ll look at a few ways to customize it. This will now be a solid copper area on your final PCB. Make sure to close it at the starting point or you’ll have problems generating gerbers later.Ī polygon with a dashed line will appear (picture 3).Ĭlick the ‘Ratsnest’ icon, and the polygon will fill with a solid copper area. Route the polygon in the shape you want it.
In the top menu bar make sure the top (red) or bottom (blue) copper layer is selected.Click ‘polygon’ icon located in the toolbar.Go to the board so we can lay down a polygon. Open Eagle and start a new schematic and PCB.
PROTEL 99SE MISSING POLYGONS EAGLE HOW TO
Here’s some notes on how to use and customize polygons in Cadsoft Eagle. Less frequently we use them to make large power traces such as with the ATX Breakout Board. We use them all the time to fill blank space on a PCB with copper connected to ground. In Eagle polygons are used to make big copper areas on a PCB that aren’t necessarily traces.
0 kommentar(er)
