Talk:TO-18

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TO-18 thermal resistance versus plastic

Intuitively, one would expect that a metal case would have better thermal conductivity to the environment, as stated in the article. As part of a current project, I spent some time comparing transistor spec sheets, and they seem to be stating something different. Take, for example, the well-known 2N2222A transistor, packaged in a TO-18 case. The spec sheet gives a maximum junction to ambient thermal resistance of 438 °C/W. The maximum allowed power dissipation is 400 mW, if the case is not attached to a heat sink.(ref). Now consider the similarly well-known 2N3904 transistor, packaged in a TO-92 plastic package. The spec sheet states that the maximum junction to ambient thermal resistance is 200 °C/W, and the maximum power dissipation is 625 mW.(ref). If the spec sheets are telling the truth, the plastic package offers a substantial thermal performance improvement over the TO-18. Perhaps I am overlooking or misunderstanding something. If not, then the text in this article which reads, "allows higher energy dissipation due to its increased thermal conductivity to the environment" will need to be changed. In any case (no pun intended), the statement needs to be sourced. Wildbear (talk) 10:24, 11 August 2010 (UTC)[reply]

Suggest merge

Instead of tiny splinters and narrating the dimension sheets in text, should we perhaps merge all the transistor package "articles" into one titles something like, oh say, "Transistor packages". Then we could give a coherent narrative of the history of transistor packaging, purposes, properties and limitations, proprietary packages and standards. The bits and scraps we have now don't tell anyone anything they can't read off the data sheets at Radio Shack. Reviewing the JEDEC dimension sheets at a level higher than the hang-cards at Radio Shack might also be an encyclopediac endeavor. --Wtshymanski (talk) 13:58, 13 May 2011 (UTC)[reply]