PCB Design Glossary
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One day through the primeval wood
Since then three hundred years have fled,
And many men wound in and out
This forest path became a lane
The years passed on in swiftness fleet,
Each day a hundred thousand rout
A hundred thousand men were led
Capacitors connect two nets of different electric potentials with an electric field. They can temporarily store energy in a small portion of a circuit. While there is no direct electrical connection between the two nets, changes in one net will affect the other.
Parts that are shipped directly from a customer to an assembly house are said to be "consigned." This method is often used for rare or hard-to-find parts.
The thickness is of copper is measured in a variety of units depending on the region. In America, for historical reasons, the thickness is measured in the pseudo-unit [ounces], which is short for [ounces]/[foot]². Other regions measure it in [micrometers], while others measure in [grams]/[millimeter]².
Integrated Circuits and Passive Components are shipped in a variety of packing options that make them easy to use with automated machinery. One option is to place the components in either a paper or plastic housing that has sprocket holes along one edge. The automated machinery uses the sprocket holes to feed the parts into the pick and place machine and index the location of parts. When an entire reel of parts is purchased and fed into the machine, it is referred to as a reel. When only a portion of that reel is purchased, the specified number of components will be counted off and cut away from the reel, leaving the customer with a cut tape.
Above is a series of reels (left) and cut tapes (right) ready to be fed into an SMT machine. Image from smtcaddy.com
The machines do have their limitations -- cut tapes cannot feed single parts, and a minimum tape length is required. This leads to something manufacturers call overage.