- Discrete transistor
Discrete transistors are
transistors that are individually packaged.The two main categories of packaging are "through-hole" (or "leaded"), and "surface-mount", also known as surface mount device (SMD).
Transistor packages are made of glass, metal, ceramic or plastic. The package often dictates the power rating and frequency characteristics. Power transistors have large packages that can be clamped to
heat sink s for enhanced cooling. Additionally, most power transistors have the collector or drain physically connected to the metal can/metal plate. At the other extreme, some surface-mount "microwave" transistors are as small as grains of sand.Often a given transistor type is available in different packages. Transistor packages are mainly standardized, but the assignment of a transistor's functions to the terminals is not: different transistor types can assign different functions to the package's terminals. Even for the same transistor type the terminal assignment can vary (normally indicated by a suffix letter to the part number- i.e. BC212L and BC212K).
ee also
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External links to datasheets
A wide range of transistors has been available since the 1960s and manufacturers continually introduce improved types. A few examples from the main families are noted below. Unless otherwise stated, all types are made from silicon semiconductor. Complementary pairs are shown as NPN/PNP or N/P channel. Links go to manufacturer datasheets, which are in
PDF format. (On some datasheets the accuracy of the stated transistor category is a matter of debate.)
* [http://www.onsemi.com/pub/Collateral/2N3903-D.PDF 2N3904] / [http://www.onsemi.com/pub/Collateral/2N3906-D.PDF 2N3906] , [http://www.onsemi.com/pub/Collateral/BC182-D.PDF BC182] / [http://www.onsemi.com/pub/Collateral/BC212-D.PDF BC212] and [http://www.onsemi.com/pub/Collateral/BC546-D.PDF BC546] / [http://www.onsemi.com/pub/Collateral/BC556B-D.PDF BC556] : Ubiquitous, BJT, general-purpose, low-power, complementary pairs. They have plastic cases and cost roughly ten cents U.S. in small quantities, making them popular with hobbyists.*
AF107 : Germanium, 0.5 watt, 250 MHz PNP BJT.*BFP183: Low power, 8 GHz microwave NPN BJT.
* [http://www.national.com/ds/LM/LM194.pdf LM394] : "supermatch pair", with two NPN BJTs on a single substrate.
* [http://www.st.com/stonline/books/pdf/docs/9288.pdf 2N2219A] / [http://www.st.com/stonline/books/pdf/docs/9037.pdf 2N2905A] : BJT, general purpose, medium power, complementary pair. With metal cases they are rated at about one watt.
* [http://www.onsemi.com/pub/Collateral/2N3055-D.PDF 2N3055] / [http://www.onsemi.com/pub/Collateral/2N3055-D.PDF MJ2955] : For years, the venerable NPN 2N3055 has been the "standard" power transistor. Its complement, the PNP MJ2955 arrived later. These 1 MHz, 15 A, 60 V, 115 W BJTs are used in audio power amplifiers, power supplies, and control.* 2SC3281/2SA1302: Made by
Toshiba , these BJTs have low-distortion characteristics and are used in high-power audio amplifiers. They have been widely counterfeited [http://sound.westhost.com/counterfeit.htm] .
* [http://www.st.com/stonline/books/pdf/docs/4491.pdf BU508] : NPN, 1500 V power BJT. Designed fortelevision horizontal deflection, its high voltage capability also makes it suitable for use in ignition systems.
* [http://www.onsemi.com/pub/Collateral/MJ11012-D.PDF MJ11012/MJ11015] : 30 A, 120 V, 200 W, high power Darlington complementary pair BJTs. Used in audio amplifiers, control, and power switching.
* [http://www.fairchildsemi.com/ds/2N%2F2N5457.pdf 2N5457] / [http://www.fairchildsemi.com/ds/2N%2F2N5460.pdf 2N5460] :JFET (depletion mode), general purpose, low power, complementary pair.* BSP296/BSP171:
IGFET (enhancement mode), medium power, near complementary pair. Used for logic level conversion and driving power transistors in amplifiers.
* [http://www.irf.com/product-info/datasheets/data/irf3710.pdf IRF3710] / [http://www.irf.com/product-info/datasheets/data/irf5210.pdf IRF5210] :IGFET (enhancement mode), 40 A, 100 V, 200 W, near complementary pair. For high-power amplifiers and power switches, especially in automobiles.External links
* [http://www.ck722museum.com/ "The CK722 Museum] ". Website devoted to the "classic" hobbyist germanium transistor
* [http://www.ee.washington.edu/circuit_archive/parts/cross.html "Jerry Russell's Transistor Cross Reference Database] ".
* [http://www.datasheetarchive.com/ "The DatasheetArchive] ". Searchable database of transistor specifications and datasheets.
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