
A pin grid array (PGA) is a type of
integrated circuit packaging. In a PGA, the package is square or rectangular, and the pins are arranged in a regular array on the underside of the package. The pins are commonly spaced 2.54 mm (0.1") apart,
and may or may not cover the entire underside of the package.
PGAs are often mounted on
printed circuit board
A printed circuit board (PCB; also printed wiring board or PWB) is a medium used in Electrical engineering, electrical and electronic engineering to connect electronic components to one another in a controlled manner. It takes the form of a L ...
s using the
through hole method or inserted into a
socket. PGAs allow for more pins per integrated circuit than older packages, such as
dual in-line package (DIP).
PGA variants
Plastic

Plastic pin grid array (PPGA) packaging was used by Intel for late-model Mendocino core
Celeron processors based on
Socket 370.
Some pre-Socket 8 processors also used a similar form factor, although they were not officially referred to as PPGA.
Flip chip

A
flip-chip pin grid array (FC-PGA or FCPGA) is a form of pin grid array in which the
die faces downwards on the top of the substrate with the back of the die exposed. This allows the die to have a more direct contact with the
heatsink or other cooling mechanism.
The FC-PGA was introduced by
Intel with the Coppermine core
Pentium III and
Celeron processors based on Socket 370, and was later used for
Socket 478-based
Pentium 4 and Celeron processors. FC-PGA processors fit into
zero insertion force (ZIF) Socket 370 and Socket 478-based
motherboard sockets; similar packages have also been used by AMD. It is still used today for mobile Intel processors.
Staggered pin
The staggered pin grid array (SPGA) is used by Intel processors based on
Socket 5 and
Socket 7.
Socket 8 used a partial SPGA layout on half the processor.

It consists of two square arrays of pins, offset in both directions by half the minimum distance between pins in one of the arrays. Put differently: within a square boundary the pins form a diagonal square
lattice. There is generally a section in the center of the package without any pins. SPGA packages are usually used by devices that require a higher pin density than what a PGA can provide, such as
microprocessors.
Ceramic
A ceramic pin grid array (CPGA) is a type of packaging used by
integrated circuits. This type of packaging uses a ceramic substrate with pins arranged in a pin grid array. Some
CPU
A central processing unit (CPU), also called a central processor, main processor or just processor, is the electronic circuitry that executes instructions comprising a computer program. The CPU performs basic arithmetic, logic, controlling, and ...
s that use CPGA packaging are the AMD
Socket A Athlons and the
Duron.
A CPGA was used by AMD for Athlon and Duron processors based on Socket A, as well as some AMD processors based on
Socket AM2
The Socket AM2, renamed from Socket M2 (to prevent using the same name as Cyrix MII processors), is a CPU socket designed by AMD for desktop processors, including the performance, mainstream and value segments. It was released on May 23, 2006, as ...
and
Socket AM2+. While similar form factors have been used by other manufacturers, they are not officially referred to as CPGA. This type of packaging uses a
ceramic
A ceramic is any of the various hard, brittle, heat-resistant and corrosion-resistant materials made by shaping and then firing an inorganic, nonmetallic material, such as clay, at a high temperature. Common examples are earthenware, porcelai ...
substrate with pins arranged in an array.
File:VIA C3 C5XL CPGA.jpg, A 1.2 GHz VIA C3 microprocessor in a ceramic package
File:Pentium P54 Socket7 PGA.jpg, 133 MHz Pentium chip in a ceramic package
Organic
An organic pin grid array (OPGA) is a type of connection for
integrated circuits, and especially
CPUs, where the
silicon
Silicon is a chemical element with the symbol Si and atomic number 14. It is a hard, brittle crystalline solid with a blue-grey metallic luster, and is a tetravalent metalloid and semiconductor. It is a member of group 14 in the periodic ...
die is attached to a plate made out of an
organic plastic
Plastics are a wide range of synthetic or semi-synthetic materials that use polymers as a main ingredient. Their plasticity makes it possible for plastics to be moulded, extruded or pressed into solid objects of various shapes. This adaptab ...
which is pierced by an array of
pins which make the requisite connections to the
socket.
File:SL3A2down.JPG, The underside of a Celeron-400 in a PPGA
File:AMD Athlon XP 2000 - Socket A - OPGA.jpg, An OPGA CPU. Note the brown color – many OPGA parts are colored green. The die is in the center of the device, and the four gray circles are foam spacers to relieve pressure from the die, caused by the heat sink.
Stud
A stud grid array (SGA) is a short-pinned pin grid array chip scale package for use in
surface-mount technology. The polymer stud grid array or plastic stud grid array was developed jointly by the
Interuniversity Microelectronics Centre (IMEC) and
Laboratory for Production Technology,
Siemens AG.
rPGA
The reduced pin grid array was used by the socketed mobile variants of Intel's Core i3/5/7 processors and features a reduced pin pitch of 1mm,
as opposed to the 1.27mm pin pitch used by contemporary AMD processors and older Intel processors. It is used in the
G1,
G2, and
G3 sockets.
See also
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Ball grid array (BGA)
*
Centered square number
*
Chip carrier
In electronics, a chip carrier is one of several kinds of surface-mount technology packages for integrated circuits (commonly called "chips"). Connections are made on all four edges of a square package; compared to the internal cavity for mou ...
- chip packaging and package types list
*
Dual in-line package
In microelectronics, a dual in-line package (DIP or DIL), is an electronic component package with a rectangular housing and two parallel rows of electrical connecting pins. The package may be through-hole mounted to a printed circuit board ( ...
(DIP)
*
Land grid array
The land grid array (LGA) is a type of surface-mount packaging for integrated circuits (ICs) that is notable for having the pins on the socket (when a socket is used) rather than the integrated circuit. An LGA can be electrically connected to a ...
(LGA)
*
Single in-line package (SIP)
*
Zig-zag in-line package (ZIP)
References
Sources
*
*
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External links
Intel CPU Processor IdentificationBall Grid Arrays: the High-Pincount Workhorses John Baliga, associate editor, ''
Semiconductor International'', 9/1/1999
Spot on component packaging 08/1998, ''
Elektronik, Produktion & Prüftechnik''
Terminology
{{Semiconductor packages
Chip carriers