European countries such as Germany, France, Italy, the Netherlands, and Belgium, as well as Eastern European countries such as Hungary, Romania, Yugoslavia, and Poland, mostly use the International Electronics Federation's semiconductor discrete device model naming method. This naming method consists of four basic parts, the symbols and meanings of each part are as follows:

Part 1: Letters indicate the materials used in the device. The forbidden band width of the material used for A-device is Eg=0.6~1.0eV. For example, Eg=1.0~1.3eV for materials used in B-devices, such as silicon and C-device materials, Eg>1.3eV, such as gallium arsenide, D- The material used in the device is Eg<0.6eV, such as indium antimonide, E-device using composite materials and materials used in photovoltaic cells.

The second part: the letter indicates the type and main features of the device. A-detector switch mixing diode, B-varactor diode, C-low frequency low power triode, D-low frequency high power triode, E-tunnel diode, F-high frequency low power triode, G-composite device and other devices, H -Magnetic Diode, Hall Element in K-Open Magnetic Circuit, L-High Frequency High Power Transistor, Hall Element in M-Closed Magnetic Circuit, P-Photosensitive Device, Q-Light Emitting Device, R-Low Power Thyristor , S-small power switch tube, T-high power thyristor, U-high power switch tube, X-doubled diode, Y-rectifier diode, Z-stabilized diode.

Part III: Use numbers or letters plus numbers to indicate the registration number. The three-digit number - the registration number of a general-purpose semiconductor device, one letter plus two digits - indicates the registration number of the dedicated semiconductor device.

Part IV: Use the letters to bin the same type of device. A, B, C, D, E┄┄ - indicates that the same type of device is indexed by a certain parameter.

In addition to the four basic parts, suffixes are sometimes added to distinguish characteristics or further classification. Common suffixes are as follows:

1. The suffix of the Zener diode model. The first part of the suffix is ​​a letter indicating the allowable error range of the stable voltage value. The letters A, B, C, D, and E respectively indicate the tolerances of ±1%, ±2%, ±5%, ±10%, ± 15%; the second part of the suffix is ​​a number indicating the integer value of the nominal stable voltage; the third part of the suffix is ​​the letter V, which represents the decimal point, and the number after the letter V is the small value of the nominal stable voltage of the Zener tube.

2. The rectifier diode suffix is ​​a number indicating the maximum reverse peak withstand voltage of the device in volts.

3. The suffix of the thyristor model is also a number, which usually indicates the voltage value of the largest reverse peak withstand voltage value and the largest reverse turn-off voltage.

Such as: BDX51- represents NPN silicon low-frequency high-power triode, AF239S- represents PNP锗 high-frequency low-power triode.