TO-8

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Hybrid integrated circuit (National Semiconductor LH033CG) in a variant of the TO-8 package with 12 leads LH033CG.jpg
Hybrid integrated circuit (National Semiconductor LH033CG) in a variant of the TO-8 package with 12 leads

In electronics, TO-8 is a designation for a standardized metal semiconductor package. TO in TO-8 stands for "transistor outline" and refers to a series of technical drawings produced by JEDEC. [1] The TO-8 package is noticeably larger than the more common TO-5 package. While originally designed for medium power transistors (that is, higher power than TO-5 but lower than TO-3) such as the 2N1483 series [2] or the AD136, [3] it is more commonly used for integrated circuits and sensors (see Variants below).

Contents

Construction

Size comparison between (left to right) TO-8, TO-5 and TO-18 packages TO-8 vs TO-5 vs TO-18.jpg
Size comparison between (left to right) TO-8, TO-5 and TO-18 packages

The typical TO-8 metal can package has a base diameter of 15.24 mm (0.600 in), a cap diameter of 12.29 mm (0.484 in), and a cap height of 7.62 mm (0.300 in). [1] The lead diameter is nominally 0.76 mm (0.030 in). The leads are arranged on a circle with a diameter of 7.16 mm (0.282 in). The minimum length of the leads is 10.16 mm (0.400 in).

Variants

Left: sensor in a variant of the TO-8 package with 8 leads and windows (right: TO-5 package variant for comparison) InfraTec-Gassensor-Planare-Detektoren-Abb3.jpg
Left: sensor in a variant of the TO-8 package with 8 leads and windows (right: TO-5 package variant for comparison)

Several variants of the original TO-8 package have the same cap dimensions but differ in the number and length of the leads (wires). Somewhat incorrectly, TO-8 is often used in manufacturer's literature as a synonym for any package with the cap dimensions of TO-8, regardless of the number of leads, or even for any package with the diameter of TO-8, regardless of the cap height and the number of leads. Light-sensitive or light-emitting devices have a transparent window, lens, or parabolic reflectors in the top of the case rather than a sealed, flat top. [4] [5] There are variants with between 2 and 16 leads. [6] For packages with more than 4 leads, the leads are usually arranged along the edges of a square with a side length of 10.16 mm (0.400 in) (rather than on a circle as in packages with up to 4 leads or for other metal can packages such as TO-101). [7] These variants usually have a tab to identify lead number 1 and an increased cap diameter of 13.97 mm (0.550 in). [7]

National standards

TO-233 is intended to replace previous definitions of TO-8. [8] [9]

Standards organizationStandardDesignation for
TO-8
JEDEC JEP95 [9] TO-233-AA
IEC IEC 60191 [lower-alpha 1] [10] C8/B13
DIN DIN 41878 [3] 8A3
EIAJ / JEITA ED-7500A [lower-alpha 1] [11] TC-6/TB-7
British Standards BS 3934 [lower-alpha 1] [10] SO-22/SB3-9
  1. 1 2 3 These standards have separate drawings for the package case and the base.

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<span class="mw-page-title-main">TO-92</span> Small and cheap semiconductor package often used for transistors

The TO-92 is a widely used style of semiconductor package mainly used for transistors. The case is often made of epoxy or plastic, and offers compact size at a very low cost.

<span class="mw-page-title-main">TO-220</span> Power semiconductor through-hole package

The TO-220 is a style of electronic package used for high-powered, through-hole components with 0.1 inches (2.54 mm) pin spacing. The "TO" designation stands for "transistor outline". TO-220 packages have three leads. Similar packages with two, four, five or seven leads are also manufactured. A notable characteristic is a metal tab with a hole, used in mounting the case to a heatsink, allowing the component to dissipate more heat than one constructed in a TO-92 case. Common TO-220-packaged components include discrete semiconductors such as transistors and silicon-controlled rectifiers, as well as integrated circuits.

<span class="mw-page-title-main">TO-3</span> Metal can semiconductor package for power semiconductors

In electronics, TO-3 is a designation for a standardized metal semiconductor package used for power semiconductors, including transistors, silicon controlled rectifiers, and, integrated circuits. TO stands for "Transistor Outline" and relates to a series of technical drawings produced by JEDEC.

<span class="mw-page-title-main">2N3904</span> Common NPN bipolar junction transistor

The 2N3904 is a common NPN bipolar junction transistor used for general-purpose low-power amplifying or switching applications. It is designed for low current and power, medium voltage, and can operate at moderately high speeds.

<span class="mw-page-title-main">2N2222</span> Common NPN bipolar junction transistor

The 2N2222 is a common NPN bipolar junction transistor (BJT) used for general purpose low-power amplifying or switching applications. It is designed for low to medium current, low power, medium voltage, and can operate at moderately high speeds. It was originally made in the TO-18 metal can as shown in the picture.

<span class="mw-page-title-main">BC548</span>

The BC548 is a general-purpose NPN bipolar junction transistor commonly used in European and American electronic equipment. It is notably often the first type of bipolar transistor hobbyists encounter and is often featured in designs in hobby electronics magazines where a general-purpose transistor is required. The BC548 is low in cost and widely available.

A semiconductor package is a metal, plastic, glass, or ceramic casing containing one or more discrete semiconductor devices or integrated circuits. Individual components are fabricated on semiconductor wafers before being diced into die, tested, and packaged. The package provides a means for connecting it to the external environment, such as printed circuit board, via leads such as lands, balls, or pins; and protection against threats such as mechanical impact, chemical contamination, and light exposure. Additionally, it helps dissipate heat produced by the device, with or without the aid of a heat spreader. There are thousands of package types in use. Some are defined by international, national, or industry standards, while others are particular to an individual manufacturer.

<span class="mw-page-title-main">TO-18</span>

In electronics, TO-18 is a designation for a style of transistor metal case. The case is more expensive than the similarly sized plastic TO-92 package. The name is from JEDEC, signifying Transistor Outline Package, Case Style 18.

<span class="mw-page-title-main">DO-204</span>

DO-204 is a family of diode semiconductor packages defined by JEDEC. This family comprises lead-mounted axial devices with round leads. Generally a diode will have a line painted near the cathode end.

<span class="mw-page-title-main">Chip carrier</span> Surface mount technology package for integrated circuits

In electronics, a chip carrier is one of several kinds of surface-mount technology packages for integrated circuits. Connections are made on all four edges of a square package; compared to the internal cavity for mounting the integrated circuit, the package overall size is large.

<span class="mw-page-title-main">Small-outline transistor</span>

A small outline transistor (SOT) is a family of small footprint, discrete surface mount transistor commonly used in consumer electronics. The most common SOT are SOT23 variations, also manufacturers offer the nearly identical thin small outline transistor (TSOT) package, where lower height is important.

<span class="mw-page-title-main">TO-5</span>

In electronics, TO-5 is a designation for a standardized metal semiconductor package used for transistors and some integrated circuits. The TO element stands for "transistor outline" and refers to a series of technical drawings produced by JEDEC. The first commercial silicon transistors, the 2N696 and 2N697 from Fairchild Semiconductor, came in a TO-5 package.

<span class="mw-page-title-main">TO-126</span>

TO-126 is a type of semiconductor package for devices with three pins, such as transistors. 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. 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.

<span class="mw-page-title-main">TO-66</span> Smaller variant of the TO-3 package

TO-66 is a type of semiconductor package for devices with three connections, such as transistors. The shape is similar to the TO-3 package, but the size is smaller. The TO-66 package is made entirely of metal and is commonly used by silicon controlled rectifiers and power transistors. In Europe, it was popularly used by the complementary germanium power transistors AD161/AD162.

References

  1. 1 2 "JEDEC TO-8 package specification" (PDF). JEDEC . Archived from the original (PDF) on 2016-04-10. Retrieved 2021-10-23.
  2. "2N1483 – 2N1486". Microsemi. 2013. Retrieved 2021-10-23.
  3. 1 2 "Germanium PNP Transistor AD136 40V / 10A DATASHEET" (PDF) (in German). Siemens. Retrieved 2021-10-25.
  4. 1 2 "LMM-244-# Planar multi channel pyroelectric detector" (PDF). InfraTec. Retrieved 2021-10-25.
  5. "Photodigm TO-8 Package". Photodigm. Retrieved 2021-10-25.
  6. "TO-8 Package". EESemi. 2008. Retrieved 2021-10-25.
  7. 1 2 Larry Davis (2012-01-21). "Transistor Package Style 12-Lead TO-8 Can". interfacebus.com. Retrieved 2021-10-25.
  8. "Index by Device Type of Registered Transistor Outlines (TO)". JEDEC Publication No. 95 (PDF). JEDEC. October 2010. Retrieved 2021-07-13.
  9. 1 2 "Header Family 0.280 Pin Circle" (PDF). JEDEC. 1976-06-01. Archived from the original (PDF) on 2016-04-10. Retrieved 2021-10-25.
  10. 1 2 "Semiconductors" (PDF). Pro Electron. 1978. pp. 215–221. Retrieved 2021-06-17.
  11. "EIAJ ED-7500A Standards for the Dimensions of Semiconductor Devices" (PDF). JEITA. 1996. Retrieved 2021-06-14.