Quad Flat Pack IC
QFP Package
A Quad Flat Pack IC [IC] is a surface mount component that contains pins, on each side of the body. Note how the leads are formed. A Quad Flat Pack is the more generic term for a Ceramic QFP [CQFP], Plastic QFP [PQFP], or metal QFP [MQFP] to provide a few examples of materials. In addition, there are other sub-classifications of a Quad Flat Pack; for example a Low Profile Quad Flatpack [having a thinner body that a normal QFP].
Surface Mount Packages |  QFP IC Package |
As with any class of integrated circuit package there are a number of different styles and of course a vast number of different pin configurations or pin outs. So no attempt is made to show all the different QFP sizes and types, only to show the general QFP IC shape, the configuration and shape of the leads. Basically almost any size is possible [within reason], with the size of the body growing as the number of pins are increased. Quad Flat Pack IC will be found having between 16 to 304 pins, which would be within the low to mid-range of package leads.
QFP Package Reductions
What is not show here is a graphic or photo of a Quad Flatpack with a thermal pad. A thermal pad is used as a heat sink to draw heat away from the body of the semiconductor and used in conjunction with a copper pad on a Printed Wiring Board [PWB]. A heat transfer path is made when the thermal pad is placed on top of a copper pad located on the PWB. Heat than flows from the IC semiconductor junction to the thermal pad and than to the copper pad of the PWB. When a thermal pad is depicted in a package drawing, a simple outline is made indicating the size and location of the pad, with a text note indicating a thermal pad. For reference a data sheet may indicate that the thermal pad of the IC is called: Powerpad thermally enhanced package
There are also packages that do not contain any leads, as in a No-lead Quad Flatpack. Of course the package still has terminals, but those terminals are pads on the package and not physical leads that protrude out from the body of the part. Again the term Quad Flatpack refers to a general class of semiconductor bodies that contain terminals on all four sides of the component body, also called a chip carrier. |  |
