TO-59 Package
Transistor Packages Styles TO-59 Case style, Bolt Mounting
TO-59 Package Drawing
The TO-59 package is a through-hole case mount device. 10-32 threads.
Case mount. Also called a Bolt-Mount package. A type of package which provides a method of readily attaching one surface of the
semiconductor device to a heat sink to achieve thermal management of the case temperature. The TO-59 Case is isolated from any of the terminal leads. The TO-59 style package could also be called a panel mount or chassis mount package. In addition some companies also refer to this package as a Metal Can, because of the can above the bolt. As of 1996 JEDEC considers the TO-59 inactive for use and has removed the case designation. In other words any new semiconductors produced after 1996 would not use this case style, or would reference the new JEDEC designation.
The TO-59 is the same style as a TO-61 Transistor case.
As with the other similar stud mount styles, this stud is threaded.
The diagram indicates a 10-32 size stud.
Terminal Leads; Lead 1 Emitter, Lead 2 Base, Lead 3 Collector.
The 2N2880 is just one example of a transistor in this package format. Of course a FET could also use this package style, having different pin functions. Use the correct wire gauge based on current draw when connecting to the package. In fact use the largest gauge wire that will fit through the openings to reduce voltage drop over the wire length.
TO-59 Semiconductor Devices;
NPN Power Transistor 2N5002, 2N5004, 2N5005, 2N2880, 2N3749.
These are example part numbers, other devices may exist.