TO-126 is a type of semiconductor package for devices with three pins, such as transistors. [1] The package is rectangular with a hole in the middle to allow for easy mounting to a board or a heat sink. On one side of the package typically a metal sheet is exposed, with the transistor die bonded to the other side of the metal sheet inside the package. [2] This allows for an efficient heat transfer from the transistor die to an external heat sink but also implies that the metal sheet is electrically connected to the die (for a bipolar junction transistor usually the collector is connected to this metal sheet).
The JEDEC TO-126 descriptor is derived from the original full name for the package: Transistor Outline Package, Case Style 126. [3] In the updated JEDEC outline system, the package is numbered as TO-225AA. [2]
STMicroelectronics refers to this package style as SOT-32. [4]
Standards organization | Standard | Designation for TO-126 |
---|---|---|
JEDEC | JEP95 [5] | TO-225AA |
IEC | IEC 60191 [6] | A56 |
DIN | DIN 41869 [7] | 12A3 |
Gosstandart | GOST 18472—88 [8] | KT-27 [a] |
Rosstandart | GOST R 57439—2017 [9] | |
Kombinat Mikroelektronik Erfurt | TGL 11811 [6] | N |
TGL 26713/09 [6] | H1B |