Staggered Pin Grid Array
Encyclopedia
Integrated circuit
An integrated circuit or monolithic integrated circuit is an electronic circuit manufactured by the patterned diffusion of trace elements into the surface of a thin substrate of semiconductor material...
package. 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
Lattice (group)
In mathematics, especially in geometry and group theory, a lattice in Rn is a discrete subgroup of Rn which spans the real vector space Rn. Every lattice in Rn can be generated from a basis for the vector space by forming all linear combinations with integer coefficients...
. As with the pin grid array
Pin grid array
A pin grid array, often abbreviated PGA, is a type of integrated circuit packaging. In a PGA, the package is square or roughly square, and the pins are arranged in a regular array on the underside of the package...
(PGA), 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.