Mentor Blogs

Here are some tips about Metric Speak that all PCB designers need to know. “Metric” is not a unit of measure. Metric is a term that describes a measurement system. You use either millimeters or microns for your PCB design units. The proper terminology to describe your working units when using the metric measurement system is millimeters or microns, not metric. Example: When doing PCB layout in Inches … Read More

PCB Grid, CAD Library

0.5 mm Pitch BGA Routing Solution There is a reasonable solution for via fanout and a routing solution for the 0.5 mm pitch BGA but we need to think outside the box. The board thickness is an important factor because it affects the hole plating aspect ratio. If you use a 1 mm PCB thickness and want to achieve a 7:1 aspect ratio (this is common among all manufacturers) then the smallest hole size … Read More

CAD Library, BGA

CAD Library Zero Component Orientations   In 2005 IPC and IEC (International Electrotechnical Commission) established a joint standard for land pattern geometries (IPC-7351/IEC 61188-5-1). In order to maintain a consistent method where these two important standards describe the component mechanical outlines, and their respective mounting platforms, a single concept must be developed that takes into … Read More

IEC Standards, IPC Standards, CAD Library

The BGA or Ball Grid Array has been around since the 1980’s but the pin pitch started out with 1.5 mm and then quickly went to 1.27 mm (50 mils) for about 15 years. Then in the late 1990’s, the 1 mm pitch BGA was introduced and every couple years a smaller pin pitch was introduced. Today 0.4 mm pitch BGA’s are in every cell phone and 0.3 mm pitch BGA’s are the next generation. … Read More

CAD Library, BGA

Placement Courtyards   I promised to post “The Anatomy of a Land Pattern” in Part 6 of my blog, but the subject must be broken down into mini-blogs as the topic covers too many issues. So let’s start with the IPC-7351B “Placement Courtyard”. The IPC-7351B standard only focuses on 2 two major aspects of the CAD library: The land size and spacing Placement courtyard All … Read More

CAD Library

Molded Body Components The next most popular component family on a PCB design layout is the Molded Body Tantalum Capacitor (CAPM). The CAPM components have an “L-Bend” component lead form. Most Molded Body Tantalum Capacitors are metric by default including their standard EIA names – 3216 – 3.2 mm X 1.6 mm 6032 – 6.0 mm X 3.2 mm 7243 - 7.2 mm X 4.3 mm 7343 – 7.3 mm X 4.3 mm The … Read More

library tools, CAD, CAD Library

I'm curious as how do PCB designers route metric pitch BGA's on a mil grid system or gridless (which consumes memory and CPU)? I can't figure why anyone would use a mil grid system for any PCB CAD library construction or PCB design layout when all the SMT component manufacturers are only producing metric pin pitch packages. This is where we note that all chip resistors and capacitors are dimensioned … Read More

CAD Library, BGA