Autodesk Eagle

Autodesk Eagle is a PCB (printed circuit board) design software that is free to use for relatively simple circuits.

Designing simple through-hole electrical circuits in Eagle

The library system is very confusing, but here is how to find some standard components for through-hole circuits. Firstly, resistors, capacitors and inductors are found in the ‘rcl’ library. Secondly, because through-hole components are nice and bendy the spacings don’t have to fit perfectly (not like surface mount). Note also that the values of the components don’t really matter when you’re adding them to the schematic, you can change the label/value later – it’s the size/spacing/footprint that counts now. The parts that we will use (and that are very generic for all through-hole circuits designed in the future are outlined in bold below.

• resistors (in the rcl library): goto R-EU_then choose either:
  • R-EU_0204/2V – this has a nice and tight 2.5mm spacing
  • R-EU_0204/2V – this has a slightly more spacey 5mm spacing
• capacitors (in the rcl library – not needed for this exercise but worth mentioning here): goto C-EU then choose either:
  • C-EU050-024X044 – this has a nice and tight 5mm spacing
  • C-EU075-032X103 – this has a nice and tight 7.5mm spacing
• potentiometers (in the rcl library) POTENTIOMETER_PT-10
• transistor-NPN library > BC548* > BC548
• led library > LED > LED3mm
• light dependant resistor (ldr) is in the photo-elements library:
  • ?1060* > V1060_21 (or any of these) is a medium spacing
  • A10 > 1050_09 (or any of these) is a smaller spacing
• connector for battery > Spark Fun-Connectors library > CONN_01 > CONN_01

Schematic

Board

You’ll need to change the size of the wires. To do this click on the (orange) ULP button > scroll down to cmd-change-brd-width click OK. Click Add all –>> then type 15 as the new wire width.

One day I will revisit this!…there is some further info on this page where I’ve used eagle to design some boards, but I want to tidy all this up! http://fab.academany.org/2018/labs/fablabbrighton/students/derek-covill/w7.html