Catalogo de marcaje de semiconductores de superficie

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THE SMD CODEBOOK

SMD Codes.
SMD devices are, by their very nature, too small to carry conventional semiconductor type numbers. Instead, a somewhat arbitrary coding system has grown up, where the device package carries a simple two- or three-character ID code. Identifying the manufacturers' type number of an SMD device from the package code can be a difficult task, involving combing throughmany different databooks. This HTML book is designed to provide an easy means of device identification. It lists well over 3,400 device codes in alphabetical order, together with type numbers, device characteristics or equivalents and pinout information. How to use the SMD Codebook To identify a particular SMD device, first identify the package style and note the ID code printed on the device. Nowlook up the code in the alphanumeric listing which forms the main part of this book by clicking on the first character shown in the left-menu. Unfortunately, each device code is not necessarily unique. For example a device coded 1A might be either a BC846A or a FMMT3904. Even the same manufacturer may use the same code for different devices!

If there is more than one entry, use the packagestyle to differentiate between devices with the same ID code. This compilation has been collected from R P Blackwell G4PMK, manufacturers' data and other sources of SMD device ID codes, pinout and leaded device equivalent information. The entries under the Manufacturer column are not intended to be comprehensive; rather they are intended to provide help on locating sources of more detailed informationif you require it. ID Code Variations Many manufacturers use an extra letter as their own identification code. If the device is from Philips it will sometimes have a lower case 'p' (or sometimes 't') added to the code; Siemens devices usually have a lower case 's'. For example, if the code is 1A, according to the table there are a number of possibilities:

• • • •

1A BC846A Phi ITT N BC546A1A FMMT3904 Zet N 2N3904 1A MMBT3904 Mot N 2N3904 1A IRLML2402 IR F n-ch mosfet 20V 0.9A

This has been a problem in the past, however recently manufacturers have been adding lower case letters which clarify the code. Many recent Motorola devices have a small superscript letter after the device code, such as SAC . (This smaller letter is merely a month of manufacture code.) Many devices fromRohm Semiconductors which start with G have direct equivalents found in the rest of the number. For example GD1 is the same as D1 which is a BCW31. Some devices have a single coloured letter (usually on extremely small diode packages). Colour, if significant, is shown in small type after the code letter.

An 'L' suffix usually indicates a low-profile package, such as an SOT323 or SC70.

SOT323.SC70.

Reverse joggle devices do present a few problems. They oftern have an 'R' in the type number. A reverse package is one where the lead have been bent up instead of down. So it's a mirror image of a conventional device. Identification is usually possible from the code number, but some manufacturers use the same code. In these cases, it's a case of looking at the device with a magnifyingglass. The leads of most normal packages come out closer to the circuit board side of the device; conversely a reverse joggle package will have them coming out closer to the 'top' of the device. Sometimes a series of devices, derived from the same die, have related type (not code) numbers. Often an 'R' will indicate a reverse joggle package, and/or a 'W' indicate a smaller package variant, such asSOT343. Sometimes similarities are also found in the code numbers. For example: Recently some manufacturers have used a symbol or lower case letter to indicate the country of manufacture. These have been ignored in the alphabetical ordering. For example:

• • •

'67' is the code for a BFP67 (SOT143 package) , '67R' is the code for the reverse joggle variant BFP67R (SOT143R), 'W67' is the...
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