More and more devices are spec'd in mm only (connectors, ICs, etc). There are two numbers from every dimension, and not all the dimensions are indicated?! Lower left corner shows mm/inches meaning the top number is the dimension in mm and the bottom number is that same dimension in inches. Lucky us! The NCP1400 datasheet has a recommend footprint: If it does not, google for the words 'recommended land pattern SOT-23' or whatever package you are looking for. If you're lucky, your datasheet will include a recommended footprint for the part you are working with. Trusting anyone else' footprint without scrutinizing it closely is a very bad idea. Remember, when in doubt create your own footprint. This is a simple enough part, we'll skip it. I find these settings useful in a handful of situations. If you want, you can change the pin definitions to indicate which pins are inputs, outputs, pwr, etc. Here is the final schematic part, centered and happy. Choose the layer you'd like to change the object to To do this:Ĭlick on the wrench, then Layer. We need to change the >NAME tag to the Name layer, and >VALUE tag to the value layer. Be sure to modify what layer these two strings are on. Once you have Name and Value placed, you'll notice that these are red when they are normally gray in color. Hold the Alt key down while your placing the Name and Value tags to get them where you want them): It's okay to use the alternate step size when moving around non-critical items like text. Click on the text button and type '>NAME' and '>VALUE'. If you do, you won't be able to hook wires to the pin tie points. Leave it on 0.1inch steps and don't use the alternate 0.01 step. NEVER change the grid size in the library editor or in the schematic layout editor. The image above shows the part centered and symmetrical. In my example part, I the right side was one block too far over so I sucked in the right side one square. Once you have everything selected (everything should be highlighted red), press F7 and right click to move the group over the center cross. To grab the group press Alt+F7, click and hold, and drag from one corner of the work area to the opposite corner - boxing in the pins and part: Pins are named, but we need to clean up how this part is sized and where the center is at. If the work area image looks corrupt, just zoom in/out to refresh the area Scroll the scroll wheel on the mouse to zoom in/outĬlick the scroll wheel (on the main work area) and hold shift to move the work area around Name it 'NCP1400':Ĭreate a red box by clicking on the 'Wire' button:ĭon't worry about centering the box at this time. Once the Library Editor is open, hit the Save icon and save your library with your name on it:Ĭlick on create a new symbol. The NCP1400 is a neat little step-up IC - we input a low voltage and get 5V out! This handy part is not in the stock Eagle library so let's create a new part for this controller IC - the NCP1400 ( datasheet). To get 5V out of a 1.5V battery, we use something called a DC to DC step-up converter. You will mess up, but you have to mess up before you can be good at it. I've done this far too many times! It takes lots of failures to get good at creating decent schematic parts and solderable footprints. Trusting someone else' part or footprint can be a sure fire way to render a pile of PCBs worthless. You are welcome to use stock Eagle libraries but use them under extreme caution. These basics will hopefully form the foundation of all your future project layouts. This is going to be very long and painful, just try to get through it. There are some recommendations here that are good to follow, but we are by no means experts at Eagle. The following tutorial breaks down how we create a new part in Eagle. Very quickly you will discover that you need to create a new part. You can dig around the Eagle libraries all you want. DXARTS: Digital Arts & Experimental Media.
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