cobito, estas serian las ventajas tecnologicamente hablando:
The advantages of LGA include:
Ease of device manufacture. Just add gold plated round pads to the bottom of the device (microprocessor). High I/O. Pin to pin spacings of 1.27 mm, 1 mm and below can be achieved with LGA. At a 1 mm pitch, 1,225 I/O's can be contained in a 35 x 35 grid that is less than 1.5 square inches (2,025 in a 45 x 45 that is less than 1.75 square inches). Low inductance. The distance from the bottom of the device being socketed to the target board can be less than 2 mm with some LGA socket designs. Ease of upgrade. Microprocessors can be easily removed and replaced. No "keep out" area required. New versions of "Z-Axis" connectors can be attached in position on one side of the target board, eliminating the need for "keep out" areas required by previous termination styles. Device cost. Devices cost less to manufacture because terminations (pins or balls) are no longer required. Elimination of co-planarity problems. LGA sockets can be manufactured for spring movement of .015" (0.4 mm), which "takes up the slack" when there is a problem with co-planarity on the bottom of the device. Low mating force requirements. Stamped and formed socket contacts, when gold plated, can be designed requiring only 20 to 35 grams of force per position to achieve reliable mating.
The disadvantages of LGA include:
Difficulty of soldering. The very high pin counts and the large footprints they necessitate require a high degree of surface mount soldering experience and sophisticated soldering equipment. This is similar to the "learning curve" that attaching BGA sockets initially requires.
Y Aqui una página con una larga explicación técnica y resultados del formato LGA (puedes leerte las conclusiones si te da pereza :D)