LibreSolar schematic symbols library

This library collects symbols used in the different Libre Solar designs.

It can be included into project in two ways:

1. Global library named LibreSolar.
2. Project-specific library named LibreSolar. This repository should ideally be included into the project as a git submodule.

Library design rules

The design rules follow the KiCad Library Convention.

General rules

• Using a 100mil grid, pin ends and origin must lie on grid nodes.
• Origin is placed in the middle of symbol.
• Field text uses a common size of 50mils.
• The Value field is prefilled with the object name.
• Description and keywords properties contain the relevant information.
• For components with a single default footprint, footprint field is filled with valid entry of the format "Footprint_Library:Footprint_Name" and is set to invisible.

Basic symbols

• The style of basic shematic symbols (resistor, capacitor, diodes, etc.) should follow the IEC 60617-2 standard.

Custom ICs (black-box components)

• Pins are grouped logically, not necessarily by pin number.
• Whenever possible, inputs are on the left and outputs are on the right.
• Power supply pins (GND and VCC) are placed left or right. Top and bottom of the symbol are reserved for name and value:
  • Reference designator centered at the top
  • Component value centered at the bottom

Schematic layout rules

• In order to be compatible with existing libraries, the grid setup should be set to 100 mils.
• The overall schematic should be grouped in hierarchical sub-schematics for easier understanding. The default schematic sheet size should be A4.
• The pins of two devices must always be connected with a wire. It is not allowed to place two devices with their pins together without a wire.
• The text size should be 50mil for standard text and 100mil for headers.
• Each component should have the following component property fields:
  • Reference
  • Value
  • Footprint
  • Datasheet (optional)
  • Manufacturer
  • PartNumber
  • Supplier (optional)
  • OrderNumber (optional)
  • Remarks (optional)
• If the tolerance or voltage of a part is relevant, it should be added in the remarks field and displayed in the schematic.