3 Things You Have to Know about the Integrated Circuit

The importance of the integrate circuit is easy to see, because all of current electronic products cannot work without ICs. They are used in virtually all electronic equipment today and have revolutionized the world of electronics. Computers, mobile phones, and other digital appliances are now inextricable parts of the structure of modern societies, made possible by the low cost of production of integrated circuits.

The advantages of integrate circuit can also explain its important role in the electronic world. The IC is made with a monocrystalline silicon on which many lithography transistors, diodes, resistors and capacitors are created using photoetching method, and then an integrated circuit is completed after connecting all components on the monocrystalline silicon according to specific requirements. Because of the features of small size, light weight, reliability and stable performance, especially the emerging of the large-scale and ultra large scale integrated circuits boosts a big forward in the development of miniaturization, reliability and flexibility of electronic devices.

The first thing you have to know is the often seen package methods for integrated circuits:

BGA (ball grid array) see figure 2

QFP (quad flat package)see figure 1

SOIC (small outline integrated circuit) see figure 5

PLCC(plastic leaded chip carrier) see figure 3

SOJ(small outline junction) see figure 4

The second is the distinguishing of IC pinout:

For the BGA package(with coordinates), Using letters A, B,C,E…to mark at the dotted or colored part widdershins, while at the clockwise direction using Numbers 1,2,3 to mark the pins. As for other packages, the first pin is counted at the counter-clockwise direction on the groove place or the colored part.

The last is the commonly used detection methods that are including on-line measurement method, off-line measurement method and substitution method.

Off-line measurement is a way that compare the DC resistance between each pin and those of the already know normal model IC before the IC has been welded in the circuits to make sure they are in normal conditions.

The on-line measurement is to measure the voltage, resistance and current values to determine whether the IC is damaged or not.

The last method is quite easy. That is using a new integrated circuit both the same in model and specification to substitute for the old one to detect it damaged or not. 

sourcing from http://www.hqew.net/events/news-article/1494.html