small-outline package

A package whose chip cavity or mounting area occupies a major fraction of the package area and whose terminals are on one or two (normally opposite) sides and consist of metal pad surfaces (on leadless versions) or leads formed around the sides and under the package or extending out from the package (on leaded versions).

NOTE 1 On leaded versions, the lead form is usually gull wing but other lead forms may be used.

NOTE 2 The quad flatpack is similar except for having terminals on four sides of the package.

References: 

JESD30D, 7/06