QFP

A QFP or Quad Flat Package is an integrated circuit package with leads extending from each of the four sides. It is used primarily for surface mounting (SMD); socketing is rare, and hole mounting is not possible. There are versions having from 32 to over 200 pins with a pitch ranging from 0.4 to 1.0 mm. Special cases include LQFP (Low profile QFP) and TQFP (Thin QFP).

The package type became common in Europe and US during the early nineties, but QFP components have been used in Japanese consumer electronics since the seventies, most often mixed with hole mounted, and sometimes socketed, components on the same printed circuit board.

A package related to QFP is PLCC which is similar but has pins with larger distance, 1.27 mm (or 1/20 inch), curved up underneath a thicker body to simplify socketing. It is very commonly used for NOR Flash memories and other programmable components.

Variants

The basic form is a flat rectangular (often square) body with pins at four sides but there exists a multiplicity of designs. These differ usually only in pin number, pitch, dimensions and used materials to improve (usually in order the thermal characteristics). A clear variation is Bumpered Quad Flat Package with extensions at the four corners to protect the pins against mechanical damage before the unit is soldered.

* BQFP: Bumpered Quad Flat Package
* BQFPH: Bumpered Quad Flat Package with heat spreader
* CQFP: Ceramic Quad Flat Package
* FQFP: Fine Pitch Quad Flat Package
* HQFP: Heat sinked Quad Flat Package
* LQFP: Low Profile Quad Flat Package
* MQFP: Metric Quad Flat Package
* PQFP: Plastic Quad Flat Package
* SQFP: Small Quad Flat Package
* TQFP: Thin Quad Flat Package
* VQFP: Very small Quad Flat Package
* VTQFP: Very Thin Quad Flat Package