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 through many 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 CodebookTo identify a particular SMD device, first identify the package style and note the ID code printed on the device.Now look 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!