Ball Grid Arrays

BGAs, or Ball Grid Arrays, require special mounting practices. A BGA is a Surface Mount Device (SMD) with a pattern, or array, of solder pads across its bottom side. Spheres of higher-temperature solder are attach to these pads. Furthermore, it takes the place of ‘leads’ such as other types of components use to connect to the PCB. This ball configuration provides the flexibility that these components require during thermal cycling (hot/cold). It can be done without stressing the physical and electrical connections. This connection is made by the balls between the component pads and the PCB land pattern.

Attachment of the Ball Grid Arrays (BGA) to the Printed Circuit Board is made by stencil printing solder paste onto the PCB’s land pattern pads. Then , placing the BGA with its spheres attach onto the pattern, with the spheres contacting their corresponding pads and pressing into the solder paste. The BGA is then reflow solder in a conveyorize oven. Since the solder paste alloy melts at a lower temperature than the BGA spheres, the paste melts and forms solder joints between the spheres and the PCB. However, the solder spheres are not allow to melt.

The BGA provides a greater number of interconnections to the PCB than is available on a conventional quad-flat pack IC. It is one of the primary advantages of the BGA.

The BGA provides a greater number of interconnections to the PCB than is available on a conventional quad-flat pack IC. It need to place on printed circuit board so pads on BGA match with pads of PCB.

Enough heat us require to heat the BGA and the PCB as it helps to reflow the solder. It joins the BGA and the PCB together.

The BGA uses surface mount technology: it connects to top layer of the PCB only. It allows circuit traces to route underneath. Moreover, it provides for High Density Interconnections (HDI) with its efficient use of board space.

The leads, between the chip inside and the pads across the bottom of the chip, are shorter, allowing for greater speed with less inductance. Heat, too, is less of a problem because the Ball Grid Array (BGA) is solder directly to the board. The heat doesn’t have to go all the way to the edges of the IC, and down its leads, in order to be dissipate.

Among the uses for Ball Grid Arrays are audio, video, data storage and processing, communication equipment, medical equipment, radar/sonar, 3D graphics, and imaging.

Contact us at sales@rushpcb.uk for more information on Ball Grid Array technology.