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The D2PAK or DDPAK, standardized as TO-263, refers to a semiconductor package type intended for surface mounting on circuit boards. They are similar to the earlier TO-220-style packages intended for high power dissipation but lack the extended metal tab and mounting hole, while representing a larger version of the TO-252, also known as DPAK, SMT package. As with all SMT packages, the pins on a D2PAK are bent to lie against the PCB surface.

A semiconductor package is a metal, plastic, glass, or ceramic casing containing one or more discrete semiconductor devices or integrated circuits. Individual components are fabricated on semiconductor wafers before being diced into die, tested, and packaged. The package provides a means for connecting the package to the external environment, such as printed circuit board, via leads such as lands, balls, or pins; and protection against threats such as mechanical impact, chemical contamination, and light exposure. Additionally, it helps dissipate heat produced by the device, with or without the aid of a heat spreader. There are thousands of package types in use. Some are defined by international, national, or industry standards, while others are particular to an individual manufacturer.


The TO-220 is a style of electronic package used for high-powered, through-hole components. The "TO" designation stands for "transistor outline". TO-220 packages have three leads. Similar packages with two, four, five or seven leads are also manufactured. A notable characteristic is a metal tab with a hole, used in mounting the case to a heatsink, allowing the component to dissipate more heat than one constructed in a TO-92 case. Common TO-220-packaged components include discrete semiconductors such as transistors and silicon-controlled rectifiers, as well as integrated circuits.

TO-252 semiconductor package for surface mounting on circuit boards

TO-252, also known as DPAK or Decawat Package, is a semiconductor package for surface mounting on circuit boards. It represents a surface-mount variant of TO-251 package, and smaller variant of the D2PAK package. It is often used for high-power MOSFETs and voltage regulators.


Surface-mount technology method for producing electronic circuits

Surface-mount technology (SMT) is a method for producing electronic circuits in which the components are mounted or placed directly onto the surface of printed circuit boards (PCBs). An electronic device so made is called a surface-mount device (SMD). In industry, it has largely replaced the through-hole technology construction method of fitting components with wire leads into holes in the circuit board. Both technologies can be used on the same board, with the through-hole technology used for components not suitable for surface mounting such as large transformers and heat-sinked power semiconductors.

See also

TO-220, through hole version of the TO-263

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