Standards allow designers to create schematics and boards in an efficient manner and to ensure ease of use for manufacture, test and repair.
When a company sets up standards for the way work is to be done, there is a consistency that can be counted on for items such as where files are located and how they are named or numbered. There is efficiency as to who is responsible for what work, and how that work will be carried out. There is predictability as to what information will be provided at the input and output of projects, when and how ECOs will be carried out, and the ability to re-use information from one job to another. When departments have procedures, time is used in a more productive manner instead of performing redundant work. Having standards reduces frustration and encourages groups working together.
Additionally, standards provide for good interaction between people. They are extremely useful for new employees who come into a company and need to know the accepted procedures of that company. They are also very useful when we need to get work done outside the company. They are also excellent for having people within the company use common information instead of feeling they need to create their own.
How to Set Up Standards
One of the best ways to setup standards within a company is to examine how other groups and companies have done it. Are there divisions within the company that have successfully setup standards that are working well? Friends and co-workers may be consulted about what they have experienced in previous organizations. People within your business network may have working standards that they can share with you as a model. One should be sure that his company has copies of any of the standards that its products must comply with, including IPC, UL, CE, DOD, telecom, RoHS, shock and vibe. All of these can be used as a starting point for setting up your standards.
Some Standards to Set
Company standards may be necessary anywhere there are multiple people using the same type of systems. They may include any process that is important to the group or company; any issues with which the company is having trouble. Those may include, but are not limited to, procedures, documentation, mechanical, libraries and design.
The company can use standards to setup many of its procedures. Those procedures decide what will be documented with flow charts and how the work will be done. The procedures will detail which personnel will be responsible for which processes and what areas will need design checks and reviews. They will also indicate how the whole system will be enforced and updated when necessary.
Documentation is an important part of the work process. Standards here might include data sheet and reference information research, handling and updating when necessary. They also might decide how the numbering and MRP system is setup and how cross-reference information will work. Standards may also determine how the prototyping and ECO processes will work for all the departments.
The mechanical department may need standarized procedures to convey board mounting and board fitting information to the other groups. This department will also decide how board dimensions and locations of any mechanical interconnections to the rest of the system will be documented so that others understand their designs and can use their output information to setup their own designs. Mechanical personnel might also be responsible for the fab and assembly drawings that convey the board and assembly documentation to the outside world.
There are several kinds of libraries involved in design, and so, there are many variables there that are primed for standardization. Many sizes and shapes of parts, text and information are possible as are the orientations of “like” parts. The same is true for schematic symbols. There are also many attribute possibilities that should be included, and padstack standards that might be set. Naming conventions are also very important and should be documented and cross-referenced. Parts and symbols may need a checking procedure to ensure that they meet all the specifications that have been documented.
The design group should have standards so that it can combine the pads, symbols, parts and the general work of several different designers. Some of the things that schematic and board designers might want to standardize are I/O specifications, netlisting, BOMs, software processes and constraints. Additionally, there are certain issues that, when done per a standard, can help in the setup of color-coding, macros and scripts, etc. The department may want to use the same standard conventions for schematic reference information and on-board documentation. Often, these groups have board-finishing checklists, design reviews and saving conventions. There are also DFM, DFT, signal integrity and EMI reviews in some companies to ensure that the board or system will perform as expected.
There are many sets of performance standards that our products must meet to be sold to the world. It is helpful if the company designing those products has taken care to ensure quality standards within its design processes. Design standards will allow designers to create schematics and boards in an efficient manner and also assure ease of use when other people are manufacturing, testing and repairing the PCB. PCD&F
Susy Webb is a senior PCB designer at Fairfield Industries in Houston, TX, and is a regular speaker at the PCB Shows, This email address is being protected from spambots. You need JavaScript enabled to view it..
