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TO-126
From Wikipedia, the free encyclopedia
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).
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