1. What is packaging?
Packaging means that the circuit pins on the silicon chip are connected to external connectors and other devices through wires. The packaging form refers to the case of mounting a semiconductor integrated circuit chip. It can not only install, fix, seal and protect the chip to improve the electrothermal performance, but also connect to the pins of the package through the wires on the chip, which pass through the wires on the printed circuit board. It is connected to other devices, connecting the internal chip to the external circuit. Because the chip must be isolated from the outside world, impurities in the air are prevented from corroding the chip circuit, which reduces the electrical performance. On the other hand, packaged chips are also easier to install and transport. This is very important, because the quality of packaging technology directly affects the performance of the chip itself and the design and manufacture of the PCB (printed circuit board) connected to it.
The ratio of chip area to packaging area is an important index to measure whether chip packaging technology is advanced or not. The closer the ratio, the better. The main considerations for packaging are as follows:
1, the ratio of chip area to package area improves the package efficiency and is as close as possible to1:1;
2。 Pins should be as short as possible to reduce the delay and the distance between pins, ensure mutual interference and improve performance;
3. According to the heat dissipation requirements, the thinner the package, the better.
Packaging is mainly divided into DIP dual in-line package and SMD patch package. Structurally, the package experienced the earliest transistor to (for example, TO-89, TO92) package, and developed to dual in-line package. Subsequently, Philip developed a small SOP package, and later derived SOJ(J type). Pin small outline package), TSOP (thin outline package), VSOP (ultra-small outline package), SSOP (reduced SOP), TSSOP (thin thinned SOP) and SOT (small outline transistor), SOIC (small outline integrated circuit) and so on. In terms of materials and media, including metals, ceramics, plastics and plastics, there are many metal packages used for circuits that require high-intensity working conditions, such as military, aerospace and so on.
Packaging has experienced the following development process:
Structural aspect: to-&; & ltGT； Dip-
Material: metal, ceramics-
Pin shape: long lead straight in-
Assembly method: through-hole insertion-
Second, the specific packaging form
1。 SOP/SOIC packaging
Sop is the abbreviation of English small outline package, which is a small form factor package. From 1968 to 1969, Philips successfully developed sap packaging technology. Later, soj(jpin small package), tsop (thin small package), vsop (very small package) and ssop (small package) gradually deduced thin transistors and small transistors. Soic (Small Integrated Circuit), etc.
2.DIP package
DIP is the abbreviation of dual in-line package, that is, dual in-line package. In the package of plug-in, the pins are led out from both sides of the package, and the packaging materials are plastic and ceramic. DIP is the most popular plug-in package at present, and its application scope includes standard logic ic, memory LSI, microcomputer circuit and so on.
3.PLCC package
PLCC is the abbreviation of plastic lead chip carrier, that is, plastic J lead chip package. PLCC package is square, 32-pin package, surrounded by pins. The overall size is much smaller than that of DIP package. PLCC package is suitable for the installation and wiring of SMT surface mount technology on PCB. It has the advantages of small volume and high reliability.
4.TQFP package
TQFP is the abbreviation of English thin square flat package, which is a thin plastic square flat package. The quad flat package (TQFP) technology effectively uses space and reduces the demand for printed circuit board space. Due to the reduced height and size, this packaging process is very suitable for space-critical applications, such as PCMCIA cards and network equipment. Almost all ALTERA CPLD/FPGA have TQFP package.
5.PQFP package
PQFP is the abbreviation of plastic square flat package, that is, plastic package square flat package. The pin spacing of PQFP package chip is very small and the pins are very thin. Generally, large or super-large integrated circuits are packaged, and the number of pins is generally above 100.
6.TSOP package
Tsop is the abbreviation of British thin small profile bag. It's a thin and small bag. The typical feature of tsop memory packaging technology is to manufacture pins around the packaging chip. Tsop is suitable for mounting wiring on PCB using smt technology (surface mounting technology). When the tsop package size is small, the parasitic parameters (large current variation, resulting in output voltage disturbance) are reduced, which is suitable for high-frequency applications, relatively convenient to operate and relatively high in reliability.
7.BGA package
BGA is the abbreviation of ball grid array package, namely ball grid array package. In the twenties and nineties of the 20th century, with the development of technology, the integration of chips has been continuously improved, the number of I-≤O pins has increased sharply, and the power consumption has also increased, so the requirements for integrated circuit packaging have become higher and higher. In order to meet the needs of development, BGA packaging began to be used in production.
The memory encapsulated by BGA technology can increase the memory capacity by 2~3 times without changing the memory size. Compared with TSOP, BGA is smaller. Better heat dissipation and electrical performance. BGA packaging technology greatly improves the storage capacity per square inch. In the storage products with the same capacity, the volume of BGA packaging technology is only 1/3 of TSOP packaging. In addition, compared with the traditional TSOP package, BGA package has a faster and more effective heat dissipation method.
? I/O terminals of BGA package are distributed under the package in the form of circular or columnar solder joint array. The advantage of BGA technology is that although the number of I/O pins increases, the pin spacing will not decrease but increase. Improve assembly output; Although the power consumption is increased, BGA can be welded by controlled chipping method to improve its electrothermal performance. Compared with the previous packaging technology, the thickness and weight are reduced; The parasitic parameters are reduced, the signal transmission delay is small, and the use frequency is greatly improved; The assembly can be used for high-reliability surface welding.
When it comes to BGA packaging, we have to mention Kingmax's patented micro BGA technology. Miniature BGA, called Miniature ball grid array in English, belongs to a branch of BGA packaging technology. 1998 was developed by Jinma company in August. The ratio of chip area to package area is not less than 1: 1. 14, which can improve the storage capacity by 2-3 times under the same volume. Compared with TSOP packaging products, it has the characteristics of small volume, good heat dissipation and good electrical performance.
The volume of memory products with tin-based packaging technology is only 1/3 of that of tsop packaging. The pins of tsop package memory come from the periphery of the chip, while the tin comes from the center of the chip. This method effectively reduces the transmission distance of signals. The length of the signal transmission line is only 1/4 of the traditional tsop technology, so the signal attenuation is also reduced. This not only greatly improves the anti-interference and anti-noise performance of the chip, but also improves the circuit performance. Tinybga packaging chip can resist external frequency as high as 300 megabytes, while traditional tsop packaging technology can only resist external frequency of 150 megabytes.
TiNYBGA memory is also thinner (the packaging height is less than 0.8 mm), and the effective heat dissipation path from the metal substrate to the radiator is only 0.36 mm Therefore, TinyBGA memory has high thermal conductivity, which is very suitable for long-term running systems and has good stability.
Advertising products include AD, ADV, OP or Ref, AMP, SMP, SSM, TMP and TMS.
Suffix description:
In the suffix 1., J stands for civil products (0-70 C), N stands for common plastic seals, and R in the suffix stands for surface stickers.
2。 Ceramic seal, suffix D or Q, industrial grade (45-85 C). The suffix h stands for round hat.
3. Suffix sd or 883 is a military product.
For example, jn dip package jr surface is sealed with jd dip ceramic.