This document describes the preferred interface for design engineers working with Small Systems Company. These procedures apply to the design of electronic PCB assemblies and systems. (We also do mechanical design.)

Note "preferred". This is the default. Other working relationships are negotiable. We can do some portion of this work for you, for example - bring your finished schematics through PCB layout to photoplot. We recommend that you review this document so we can each begin with the same expectations and then discuss variations as needed.

Design Procedures at Small Systems

The Design Engineer provides -

Specifications of signal timing and electrical parameters may be omitted from these copies, and probably should be when extra pages are involved.

This BOM should be provided at the outset of the design process or ASAP, because purchasing cannot begin until this information is submitted, and purchasing is usually the longest task to complete. A decision on the quantity of assemblies to be built on the first run should be made as soon as the BOM is prepared, again, so purchasing can begin.

A pencil schematic should be drawn by any means suitable to the engineer. The schematic should show signal names attached to every pin of every component in the design. Drawn wires are optional. A netlist, in any human-readable form, may be substituted for a schematic, as long as it is complete.

Block diagrams are helpful, but not required.

Notes should be included with the schematic or netlist which specify any special treatment required on any signals, such as maximum or matched lengths, reduced capacitance, inductance, or noise, etc.

Bypass capacitors should be included in the design, with indications of how many should be adjacent to which component.

An effort should be made to use components in the design which already exist in your company's manufacturing database.

When the design is completed, the engineer should complete a paper APSS (approved parts specification sheet) for each new component specified. Part names and part numbers will be assigned according to your company's part naming convention. However, our system has certain constraints and preferences which are documented on pages one and two of "Electronic Part and Signal Naming Conventions for Use with Schema and PADS PCB Software" , Hileman, 1989.

Small Systems Engineering Services will provide -

The engineer is responsible for -

ssdesign.html 7/18/97 R L Hileman
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