TO-66 is a type of semiconductor package for devices with three connections, such as

transistors A transistor is a semiconductor device used to Electronic amplifier, amplify or electronic switch, switch electrical signals and electric power, power. It is one of the basic building blocks of modern electronics. It is composed of semicondu ...

. The shape is similar to the TO-3 package, but the size is smaller. The TO-66 package is made entirely of metal and is commonly used by silicon controlled rectifiers and power transistors. In Europe, it was popularly used by the complementary

germanium Germanium is a chemical element; it has Symbol (chemistry), symbol Ge and atomic number 32. It is lustrous, hard-brittle, grayish-white and similar in appearance to silicon. It is a metalloid or a nonmetal in the carbon group that is chemically ...

power transistors AD161/AD162. The TO-66 package consists of a diamond-shaped base plate with diagonals of and . The plate has two mounting holes on the long diagonal, with the centers spaced apart. A cap attached to one side of the plate and under which the semiconductor chip is located, brings the total height to up to . Two pins on the other side of the plate are isolated from the package by individual glass-metal seals. The metal case forms the third connection (in the case of a bipolar junction transistor this is typically the collector).

Variants

TO-66 is often used as a synonym for any of the variants that have the same footprint (i.e. position of mounting holes and pins) as TO-66.

TO-123

TO-123 reduces the maximum thickness of the base plate from to .

TO-124

TO-124 increases the maximum thickness of the base plate from to and the maximum total height from to .

TO-213

TO-213 is intended to replace previous definitions of flange-mounted packages with a pin spacing. The different outlines are now defined as variants of TO-213: TO-66 is renamed to TO-213-AA, TO-123 to TO-213-AB, TO-124 to TO-213-AC.

National standards

References

External links

TO-66 Package
EESemi.com Semiconductor packages {{Electronics-stub