Land grid array

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The land grid array (LGA) is a type of surface-mount packaging used for integrated circuits. It can be electrically connected to a PCB either by the use of a socket or by soldering directly to the PCB.

Contents 1 Use in microprocessors 2 External links 3 List of microprocessor LGA sockets 3.1 AMD 3.2 Intel 4 References 5 See also

[edit] Use in microprocessors

The LGA is used as a physical interface for microprocessors of the Intel Pentium 4, Intel Xeon, Intel Core 2 and AMD Opteron families. Unlike the pin grid array (PGA) interface found on most AMD and older Intel processors, there are no pins on the chip; in place of the pins are pads of bare gold-plated copper that touch pins on the motherboard.

While LGA sockets have been in use as early as 1996 by the MIPS R10000 and HP PA-8000 processors, the interface did not gain widespread use until Intel introduced their LGA platform starting with the 5x0 and 6x0 sequence Prescott core Pentium 4 in 2004. All Pentium D and Core 2 desktop processors currently use an LGA socket. As of Q1 2006 Intel switched the Xeon server platform to LGA starting with the 5000-series models. AMD introduced their server LGA platform starting with the 2000-series Opteron in Q2 2006. AMD offers the Athlon 64 FX-74 on socket 1207FX through ASUS's L1N64-SLI WS motherboard as the only desktop LGA solution in the desktop market from AMD currently.

The Intel desktop LGA socket is dubbed Socket 775 or Socket T while the server variant is dubbed Socket J or Socket 771. Intel supposedly decided to switch to an LGA socket because it provides a larger contact point, allowing, for example, higher clock frequencies. The LGA setup provides higher pin densities, allowing more power contacts and thus a more stable power supply to the chip. Motherboard vendors have complained that LGA packaging was introduced solely to move the burden of bent pin problems from Intel to the electronics vendors.^{[citation needed]}

The AMD server LGA socket is designated Socket 1207 (sometimes referred to as Socket-F) Similar to Intel, AMD decided to use an LGA socket because it allows higher pin densities. The required size of a 1207-pin PGA would simply be too large and would consume too much space on motherboards.

[edit] External links

• Socket F to debut in July
• Two more pictures of Socket F
• LGA interface

[edit] List of microprocessor LGA sockets

[edit] AMD

• Socket F

[edit] Intel

• Socket T
• Socket J
• Socket B
• Socket R

[edit] References

[edit] See also

• Dual in-line package (DIP)
• Pin grid array (PGA)
• Ball grid array (BGA)