In electronics, the term copper pour refers to an area on a
printed circuit board
A printed circuit board (PCB), also called printed wiring board (PWB), is a Lamination, laminated sandwich structure of electrical conduction, conductive and Insulator (electricity), insulating layers, each with a pattern of traces, planes ...
filled with
copper
Copper is a chemical element; it has symbol Cu (from Latin ) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkish-orang ...
(the metal used to make connections in printed circuit boards). Copper pour is commonly used to create a
ground plane
In electrical engineering, a ground plane is an electrically conductive surface, usually connected to electrical ground. Ground planes are typically made of copper or aluminum, and they are often located on the bottom of printed circuit boards ...
. Another reason for using copper pour is to reduce the amount of
etching
Etching is traditionally the process of using strong acid or mordant to cut into the unprotected parts of a metal surface to create a design in intaglio (incised) in the metal. In modern manufacturing, other chemicals may be used on other type ...
fluid used during manufacturing.
Features
A distinctive feature of copper pour is the ''backoff'' (or ''stand-off'') - a certain distance between the copper pour and any tracks or pads not belonging to the same electrical net. A copper pour therefore looks like it flows around other components, with the exception of pads which are connected to the copper pour using
thermal connections.
Many early PCBs have a "hatched copper pour", sometimes called a "cherry pie lattice".
PCB designers today almost always use completely solid areas of copper pour that completely cover the remaining area outside those tracks, pads, and stand-off regions.
While solid copper pour provides better resistive characteristics, hatched copper pour is used to balance the heat and dilatation on both sides of the board in order to avoid warping of certain substrate.
Heating might cause gas bubbles between solid copper pour and certain substrates. Furthermore, it might be possible to adjust the impedance of high frequency traces by using hatched copper pour in order to reach better signal quality.
See also
*
References
External links
Integrated Circuit ComponentsPrinted Circuit Board Assembly
{{DEFAULTSORT:Copper Pour
Printed circuit board manufacturing