An IC chip (Integrated Circuit) is a chip formed by placing a large number of microelectronic components (transistors, resistors, capacitors, diodes, etc.) forming an integrated circuit on a plastic substrate. Almost all chips currently seen can be called IC chips.

An integrated circuit (IC) is a miniature electronic device or component. Using a certain process, the transistors, diodes, resistors, capacitors, and inductors required in a circuit, as well as the wiring interconnections, are fabricated on a small piece or several small pieces of semiconductor wafers or dielectric substrates, and then packaged in a casing to become a miniature structure with the required circuit function. All components are structurally integrated into a whole, enabling electronic components to take a big step towards miniaturization, low power consumption, and high reliability. It is represented by the letters "IC" in the circuit. The inventors of the integrated circuit are Jack Kilby (silicon-based integrated circuit) and Robert Noyce (germanium-based integrated circuit). Today, most applications in the semiconductor industry use silicon-based integrated circuits.

There are many ways to classify chips. The most important and complex way is to classify them according to their packaging method, which is also the most widely used classification method in the current electronics market.

Packaging is the process of assembling an integrated circuit into a final chip product. Simply put, it is the process of placing the integrated circuit die produced by the foundry on a substrate that plays a supporting role, leading out the pins, and then fixing and packaging it into a whole.

There are as many as 72 packaging forms currently available. Let's start by introducing some of the most common packaging forms.

I. DIP (Dual In-line Package) Dual in-line package

Dual in-line package. Also known as DIP packaging, abbreviated as DIP or DIL (this is the commonly used name for European semiconductor manufacturers). One of the plug-in packages, the pins are led out from both sides of the package. The packaging materials are plastic and ceramic. DIP is the most popular plug-in package, and its applications include standard logic ICs, memory LSIs, and microcomputer circuits. The pin spacing is 2.54mm, and the number of pins ranges from 6 to 64. The package width is usually 15.2mm. Some refer to packages with widths of 7.52mm and 10.16mm as skinny DIP and slim DIP (narrow DIP), respectively. However, in most cases, no distinction is made, and they are simply referred to as DIP.

In addition, ceramic DIP sealed with low-melting-point glass is also called cerdip (ceramic dual in-line package sealed with glass, used in ECL RAM, DSP (digital signal processor) circuits, etc.). Cerdip with a glass window is used in UV erasable EPROMs and microcomputer circuits with internal EPROMs. The pin spacing is 2.54mm, and the number of pins ranges from 8 to 42. In Japan, this package is represented as DIP-G (G means glass sealed).

However, with the high integration of CPUs, DIP packaging quickly exited the historical stage. Their "footprints" can only be seen on old VGA/SVGA graphics cards or BIOS chips.

• Cerdip—ceramic dual in-line package sealed with glass, used in ECL RAM, DSP (digital signal processor) circuits, etc. Pin spacing is 2.54mm, and the number of pins ranges from 8 to 42. In Japan, this package is represented as DIP-G (G means glass sealed).
• DIC—another name for ceramic DIP (including glass sealed)
• DIL—another name for DIP, often used by European semiconductor manufacturers.
• SDIP—shrink DIP. One of the plug-in packages, the shape is the same as DIP, but the pin spacing (1.778mm) is smaller than DIP (2.54mm), hence the name. Number of pins From 14 to 90. Also called SH-DIP The materials are ceramic and plastic.
• SK-DIP —A type of DIP. Refers to a width of 7.62mm, Pin spacing is 2.54mm narrow DIP. Usually referred to as DIP.
• SL-DIP—A type of DIP. Refers to a width of 10.16mm, pin spacing of 2.54mm narrow DIP. Usually referred to as DIP.

II. SIP (single in-line package) single in-line package

Single in-line package. Abbreviated as SIP or SIL (European semiconductor manufacturers mostly use the name SIL). The pins are led out from one side of the package, arranged in a straight line. When assembled on a printed circuit board, the package is in a vertical position. The pin spacing is usually 2.54mm, and the number of pins ranges from 2 to 23, mostly custom products. The shapes of the packages vary. Some packages with the same shape as ZIP are also called SIP.

III. SOP (Small Out-Line Package) small outline package Dual row surface mount package

Small outline package is a very common component packaging form. One of the surface mount packages, the pins are led out from both sides of the package in a gull-wing shape (L-shape). The materials are plastic and ceramic. Also called SOL and DFP. In addition to being used for memory LSIs, SOP is also widely used in circuits such as relatively small-scale ASSPs. In the field where the number of input and output terminals does not exceed 10-40, SOP is the most widely used surface mount package. The pin spacing is 1.27mm, and the number of pins ranges from 8 to 44. In addition, SOP with a pin spacing of less than 1.27mm is also called SSOP; SOP with a mounting height of less than 1.27mm is also called TSOP. There is also a SOP with a heat sink.

SOP packaging has a wide range of applications, and it has gradually derived SOJ (J-lead small outline package), TSOP (thin small outline package), VSOP (very small outline package), SSOP (shrink SOP), TSSOP (thin shrink SOP), and SOT (small outline transistor), SOIC ( Small outline integrated circuit ) etc., which have played a pivotal role in integrated circuits. For example, the frequency generator on the motherboard uses SOP packaging.

• SSOP (Shrink Small Outline Package) with pin centers less than 1.27mm;
• TSOP (Thin Small Outline Package) with a mounting height of less than 1.27mm;
• VSOP (Very Small Outline Package); TSSOP (Thin Shrink Small Outline Package);
• SOT (Small Outline Transistor); SOP with a heat sink is called HSOP;
• Some semiconductor manufacturers call SOP without a heat sink SONF (Small Out-Line Non-Fin);
• Some manufacturers call the wide-body SOP SOW (Small Outline Package (Wide-Jype))

IV. QFN (quad flat non-leaded package) four-side leadless flat package

Four-side leadless flat package, a packaging for high-speed and high-frequency ICs. One of the surface mount packages, often called LCC. QFN is the name specified by the Japan Electronics and Information Technology Industries Association. The package has electrodes on four sides Electrode contacts Because it is leadless, the mounting area is smaller than QFP, and the height is lower than QFP. However, when Printed circuit board Stress occurs between the package and the package, the stress cannot be relieved at the electrode contact. Therefore, it is difficult for the electrode contacts to have as many pins as the QFP pins, generally ranging from 14 to 100.

The materials are ceramic and plastic. When there is an LCC mark, it is basically a ceramic QFN. The electrode contact center distance is 1.27mm. Plastic QFN is a low-cost package based on a glass epoxy resin printed circuit board substrate. The electrode contact center distance is 1.27mm, as well as 0.65mm and 0.5mm. This package is also called plastic LCC, PCLC, P-LCC, etc.

• PCLP - Printed Circuit Board Leadless Package. The name used by Fujitsu Limited of Japan for plastic QFN (plastic LCC) (see QFN). The pin center distance has two specifications: 0.55mm and 0.4mm. It is currently under development.
• P-LCC - Sometimes it is another name for plastic QFJ, and sometimes it is another name for QFN (plastic LCC). Some LSI (large-scale integrated circuit) manufacturers use PLCC to represent packages with leads and P-LCC to represent leadless packages to distinguish them.

V. QFP (quad flat package) four-side pin flat package

Four-side pin flat package, one of the surface mount packages, with pins extending from four sides in a gull-wing (L) shape. The substrate is available in ceramic, metal, and plastic. Plastic QFP is the most popular multi-pin LSI (large-scale integrated circuit) package. When the material is not specifically indicated, it is mostly plastic QFP. The pin center distance has various specifications such as 1.0mm, 0.8mm, 0.65mm, 0.5mm, 0.4mm, and 0.3mm. The maximum number of pins in the 0.65mm center distance specification is 304.

In Japan, QFP with a pin center distance of less than 0.65mm is called QFP (FP). However, the Japan Electronics and Information Technology Industries Association has reevaluated the shape specifications of QFP. Instead of differentiating by pin center distance, it is divided into three types according to the thickness of the package body: QFP (2.0mm～3.6mm thick), LQFP (1.4mm thick), and TQFP (1.0mm thick).

In addition, some LSI manufacturers specifically call QFP with a pin center distance of 0.5mm a shrink QFP or SQFP, VQFP. However, some manufacturers also call QFP with pin center distances of 0.65mm and 0.4mm SQFP, resulting in some confusion in naming. The disadvantage of QFP is that when the pin center distance is less than 0.65mm, the pins are easily bent.

In order to prevent pin deformation, several improved QFP varieties have emerged. For example, BQFP (see BQFP) with resin buffer pads at the four corners of the package; GQFP (see GQFP) with a resin protective ring covering the front end of the pins; TPQFP (see TPQFP) with test bumps in the package body, which can be tested by placing it in a special fixture to prevent pin deformation. In logic LSIs, many development products and high-reliability products are packaged in multilayer ceramic QFPs. Products with a minimum pin center distance of 0.4mm and a maximum number of pins of 348 have also been launched. In addition, there are also glass-sealed ceramic QFPs (see Gerqad).

• BQFP - Buffered Quad Flat Package. American semiconductor manufacturers mainly use this package in microprocessors and ASICs. The pin center distance is 0.635mm, and the number of pins ranges from 84 to 196.
• Cerquad - One of the surface mount packages, namely glass-sealed ceramic QFP, used for packaging logic LSI circuits such as DSPs. Cerquad with a window is used for packaging EPROM circuits. The heat dissipation is better than plastic QFP, and it can allow a power of 1.5～2W under natural air cooling conditions. However, the packaging cost is 3～5 times higher than that of plastic QFP. The pin center distance has various specifications such as 1.27mm, 0.8mm, 0.65mm, 0.5mm, and 0.4mm. The number of pins ranges from 32 to 368.
• FP - Flat Package, one of the surface mount packages. QFP with a pin center distance of less than 0.65mm, another name for QFP, used by some semiconductor manufacturers. QFP with a pin center distance of less than 0.65mm.
• FQFP - Small pin center distance QFP. Usually refers to QFP with a pin center distance of less than 0.65mm. Used by some semiconductor manufacturers.
• CQFP - Quad Flat Package with Protective Ring. One of the plastic QFPs, the pins are shielded by a resin protective ring to prevent bending and deformation. Before assembling the LSI onto the printed circuit board, the pins are cut from the protective ring and made into a gull-wing shape (L shape). This package has been mass-produced by Motorola in the United States. The pin center distance is 0.5mm, and the maximum number of pins is about 208.
• LQFP - Thin QFP. Refers to QFP with a package body thickness of 1.4mm, which is the name used by the Japan Electronics and Information Technology Industries Association according to the newly established QFP shape specifications.
• QIC - Another name for ceramic QFP. Used by some semiconductor manufacturers (see QFP, Cerquad).
• QIP - Another name for plastic QFP. Used by some semiconductor manufacturers (see QFP).
• MQFP - A classification of QFP according to the JEDEC (Joint Electron Device Engineering Council) standard. It refers to a standard QFP (see QFP) with a pin center distance of 0.65mm and a body thickness of 3.8mm to 2.0mm.