One, DIP dual in-line package
DIP (DualIn-line Package) refers to the use of dual in-line method of packaging integrated circuit chip, the vast majority of small and medium-sized integrated circuits (IC) are selected this packaging method, the pin count is generally not more than 100. The DIP chip CPU chip has two rows of pins, the need to pierce the chip socket with DIP structure. Of course, can also be directly inserted in the same number of holes and a few placed on the circuit board for welding. DIP-packaged chips should be especially careful when inserting and removing from the chip receptacle to avoid damage to the pins.
DIP package has the following characteristics:
1. Suitable for PCB (printed circuit board) perforation welding, easy to operate.
2. Chip area and the ratio between the packaging area is larger, so the volume is also larger.
Intel series CPU 8088 on the use of this packaging method, cache (Cache) and the early memory chip is also the packaging method.
Second, QFP plastic square flat package and PFP plastic flat package
QFP (Plastic Quad Flat Package) package between the chip pin is very small, the pin is very fine, the general large-scale or very large integrated circuits are using this packaging method, the pin count is generally more than 100. Encapsulated chips in this way must use SMD (external device equipment skills) to chip and the motherboard welded together. SMD devices used in the chip do not have to punch on the motherboard, usually in the appearance of the motherboard has a good design of the corresponding pin of the solder joints. The chip feet at the corresponding solder joints, you can complete the welding with the motherboard. In this way welding up the chip, if you do not have special tools is difficult to open down.
PFP (Plastic Flat Package) method package chip and QFP method is basically the same. The only difference is that QFP is generally square, and PFP can be both square and rectangular.
The QFP / PFP package has the following features:
1. Suitable for SMD appearance device technology on the PCB circuit board device wiring.
2. Suitable for high frequency applications.
3. Convenient operation and high reliability.
4. The ratio between the chip area and the package area is small.Intel series CPU 80286, 80386 and some 486 motherboard selection of this packaging method.
Third, PGA pin grid array package
PGA (Pin Grid Array Package) chip packaging method in the chip table has a number of square array of pins, each square array pin along the chip around the interval must be placed. According to the number of pins, can be surrounded by 2-5 laps. Device, the chip pierced the special PGA socket. In order to make the CPU more convenient to install and disassemble, starting from the 486 chip, showing a ZIF called the CPU socket, specifically used to meet the PGA package CPU in the device and disassembly requirements. ZIF (Zero Insertion Force Socket) refers to the zero insertion force of the socket. The wrench on this socket quietly lifted, CPU can be very simple and easy to pierce the socket. And then press the wrench back to the original, the use of the socket itself, the special structure of the generated pressure, the CPU pin and socket firmly touch, there must be no bad touch problems. And open the CPU chip only need to quietly lift the socket wrench, the pressure release, CPU chip can be easily removed.
PGA package has the following characteristics:
1. Plug and pull operation more convenient, high reliability.
2. can be used to a higher frequency.
Intel series CPU, 80486 and Pentium, Pentium Pro are selected this package method.
Four, BGA ball grid array package
With the development of integrated circuit technology, the packaging requirements of the integrated circuit more stringent. This is due to the packaging skills related to the functionality of the product, when the IC frequency exceeds 100MHz, the traditional packaging method may occur the so-called "CrossTalk" phenomenon, and when the IC pin count greater than 208 Pin, the traditional packaging method Its difficulty. Therefore, in addition to the use of QFP packaging methods, and now most of the high-foot chip (such as graphics chips and chipsets, etc.) are turned to use BGA (Ball Grid Array Package) packaging skills. BGA a presentation will become the CPU, the motherboard on the South / North Bridge chip and other high-density, high performance, multi-pin package the best choice.
BGA packaging skills can be divided into five categories:
1.PBGA (Plasric BGA) substrate: generally 2-4 layers of organic materials composed of multi-layer board. Intel series CPU, Pentium II, III, IV processors are selected this package method.
2.CBGA (CeramicBGA) substrate: the ceramic substrate, the chip and the substrate between the electrical connection is generally used flip chip (FlipChip, referred to as FC) device method. Intel series CPU, Pentium I, II, Pentium Pro processors have chosen this packaging method. 3.FCBGA (FilpChipBGA) substrate: hard multilayer substrate.
4.TBGA (TapeBGA) substrate: the substrate is a soft 1-2 layer PCB circuit board.
5.CDPBGA (Carity Down PBGA) substrate: refers to the package center with a low type of chip area (also known as cavity).
The BGA package has the following features:
1. The number of I / O pins increases, but the spacing between the pins is much larger than the QFP package, increasing the yield.
2. Despite the addition of power to the BGA, it is possible to improve the electrothermal performance due to the choice of controlled trap chip welding.
3. Signal transmission delay is small, habit frequency greatly improved.
4. Assembly can be used coplanar welding, reliability greatly improved.
BGA packaging method after 10 years of development has entered the practical stage. In 1987, Citizen Corporation of Japan began to develop a chip that encapsulates the ball grid array (ie, BGA). Then, Motorola, Compaq and other companies also joined the team to develop BGA. In 1993, Motorola took the lead in using BGA for mobile phones. In the same year, Compaq is also on the workstation, PC computer to be used. Until five or six years ago, Intel in the computer CPU (ie leap II, leap III, leap IV, etc.), and chipset.