Electronic Components: Part Three of a Four-Part Monthly Series
In this series we have discussing the important role that good
documentation control has in protecting your intellectual property. Losing
control of your documentation package to the manufacturer or engineering
firm that helped design your product is problematic to say the least.
Limited supply mobility, costly re-engineering, and rights protection
issues are all too common results of not tightly securing your
documentation package.
The following are some of the basic electronic files that need to be
included in the documentation package.
Schematic
A schematic shows all components and interconnections. It is very
difficult and error prone to reconstruct by reverse engineering the
product, so it is important that this be maintained. As with 3D CAD data
you should keep this in the original native format as well as PDF
documentation that anyone can read.
Gerber Files
The Gerber files define the bare printed circuit board, including traces,
holes, and physical dimensions. It is best to have these in the Gerber
format as well as PDF files.
Bill of Materials
It is vital that you have a detailed BOM for at a minimum the electronic
components. An overall BOM is also important, but it is much easier to
reconstruct a mechanical BOM if necessary. Electronic components on the
PCB are often indistinguishable. A BOM should have a description of the
functional characteristics of the part (e.g. Capacitor, 0.1 uf X7R 10%
ceramic 16V 0603), as well as specific approved vendors and their part
numbers, and a circuit designator reference that matches the schematic
(e.g C3, R5).
Component Data Sheets
While not as critical, it is good to have copies of supplier data sheets
for critical components defining the characteristics.
Hex Code
The Hex Code is the software that actually gets programmed into the
microprocessor. If you have this file you can duplicate your product, but
without the source code it will be very difficult to make changes.
Source Code
The Source Code is the human-readable version of the code. If you hire an
outside programmer it is critical that part of your contract is that you
get a copy of the source code. Without the source code it is very
difficult to make changes in the future, or use the software as a basis
for other products in your line. In addition, the source code should be
well commented so other programmers can understand the function and
intent. It is a good idea to ask for source samples of other code the
programmer has written to make sure it is adequately commented.
Programming Instructions
This document explains how the hex code should be programmed into the
chip. Often there are special bit settings or serialization that needs to
be configured that may not be specified in the source code. You need to
know what these are.
Documentation Control, electronic components
