Marking transistors - what it is? Types, parameters and characteristics of transistors, marking

The transistor is the main component of any electrical circuit. It is a kind of amplifying key. At the heart of this semiconductor device is a silicon or germanium crystal. Transistors are unipolar and bipolar and, accordingly, field and bipolar. According to the type of conductivity, they are of two types - direct and reverse. For beginners of radio amateurs, the main problem is the recognition and decoding of the encoding of these elements. In this article we will consider the main types of recording of both domestic and foreign products, and also we will analyze what the labeling of transistors means.

Types of record

Transistor manufacturers use two basic types of encryption - color and code markings. However, neither one nor the other does not have uniform standards. Each plant that produces semiconductor devices (transistors, diodes, zener diodes, etc.) receives its code and color codes. One can meet transistors of the same group and type, manufactured by different plants, and they will be labeled differently. Or vice versa: the elements will be different, and the designations on them will be identical. In such cases, they can be distinguished only by additional signs. For example, along the length of the emitter and collector leads or on the color of the opposite (or face) surface. The marking of the field-effect transistors is no different from the marks on other devices. The same situation with semiconductor elements of foreign production: each manufacturer uses its own types of designations.

Transistors in the case of KT-26 type

Consider what it means to mark the transistors of domestic production. This type of case is the most popular among manufacturers of semiconductor devices. It has the shape of a cylinder with one sloping side, three outlets come out from the lower base. In this case, use the principle of mixed marking, containing both code symbols, and color. On the upper base, a colored dot is assigned, meaning the group of the transistor, and on the oblique side - a code symbol or color point corresponding to the type of device. In addition to the type, the year and month of production can be applied.

The following color marking of the transistors is used to designate the group: group A corresponds to a dark red dot, B is yellow, B is dark green, G is blue, D is blue, E is white, G is dark brown, - orange, L - light tobacco, M - gray.

The type is indicated by means of the symbols and colors indicated below.

• KT203 corresponds to a right-angled triangle (down and right) and a dark red dot.
• KT208 is a small circle (there is no color marking for this type).
• K209 - a rhombus (a gray dot).
• K313 - a symbol that resembles an inverted letter T (orange dot).
• KT326 is an inverted equilateral triangle (brown dot).
• KT339 is an equilateral triangle (blue point).
• KT342 is a quarter of a circle (blue dot).
• KT502 - half circle (yellow dot); KT503 - circle (white dot).
• KT3102 - a rectangular triangle with the legs up and to the left (dark green dot).
• KT3157 - right-angled triangle left and down (no color designation).
• K366 is the letter T (there is no color).
• KT6127 - inverted letter P.
• KT632 - there is no symbolic designation (silver point).
• KT638 - without a symbol (orange dot).
• KT680 - the letter G.
• KT681 is a vertical stick.
• KT698 is the letter P.

Marking of the year and month of manufacture

In accordance with GOST 25486-82, two letters or a letter and a digit are used to designate the date. The first symbol corresponds to the year, and the second symbol corresponds to the month. This kind of encoding is used not only for transistors, but also for other domestic semiconductor elements. On foreign devices, the date is indicated by four digits, the first two of which correspond to the year, and the last to the week number. Consider what the code marking of transistors means, corresponding to the date of manufacture. Year of manufacture / symbol: 1986 - U, 1987 - V, 1988 - W, 1989 - X, 1990 - A, 1991 - B, 1992 - C, 1993 - D, 1994 - E, 1995 - F, 1996 - N, 1997 - I, 1998 - K, 1999 - L, 2000 - M, etc. Month of release: the first nine months correspond to figures from 1 to 9 (January - 1, February - 2), and the last - to the initial letters of the word: October - Oh, November - N, December - D.

Transistors in the case of KT-27 type

It is customary to apply these semiconductor elements to either an alphanumeric code or a cipher consisting of geometric figures. Consider what the graphic labeling of transistors means.

• KT972A - one "recumbent" rectangle.
• KT972B - two rectangles: the left one lies, the right one stands.
• KT973A - one square.
• KT973B - two squares.
• KT646A - one triangle.
• KT646B - left circle, right triangle.

In addition, there is an additional color marking of the end of the case, which is the opposite of the conclusions:

• CT 814 - gray-beige;
• KT 815 - lilac-violet or gray;
• KT 816 - pink-red;
• CT 817 - gray-green;
• CT 683 is purple;
• KT9115 - blue.

Transistors of the KT814-817 series of group B can be marked only by staining the end face, without applying the symbol code.

European system PRO-ELECTRON

The marking of transistors and other semiconductor devices from European manufacturers is as follows. The code is a character entry. The first letter means semiconductor material: silicon, germanium, etc. The most common silicon, it corresponds to the letter B. The next symbol is the type of device. Next is the serial number of the product. This number has several ranges. For example, if the numbers from 100 to 999 are specified, then these items belong to general-purpose products, and if they are preceded by a letter (Z10-A99), these semiconductors are considered to be special or industrial parts. In addition, an additional symbol of the device modification can be added to the common encoding. It is determined directly by the manufacturer of semiconductor elements.

The first symbol (material): A - germanium, B - silicon, C - gallium arsenide, R - cadmium sulphide. The second element means the type of transistor: C - low-power low-frequency; D - powerful low-frequency; F - low-power high-frequency; G - several devices in one housing; L - powerful high-frequency; S - low-power switching; U is a powerful switching.

American system JEDEC

American manufacturers of semiconductor devices use a character encoding consisting of four elements. The first digit indicates the number of n-n transitions: 1 - diode; 2 - transistor, 3 - thyristor; 4 - optocoupler. The second letter indicates the group. The third sign is the serial number of the element (range from 100 to 9999). The fourth symbol is the letter corresponding to the modification of the device.

Japanese JIS system

This system consists of symbols and contains five elements. The first digit corresponds to the type of semiconductor device: 0 - photodiode or phototransistor; 1 - the diode; 2 - transistor. The second element is the letter S, it is placed on all elements. The next letter corresponds to the type of transistor: A - high-frequency PNP; B - low-frequency PNP; C - high-frequency NPN; D - low-frequency NPN; H - unijunctioned; J - field with N-channel; K - field with P-channel. Next comes the serial number of the product (10 - 9999). The last, the fifth, element is a modification of the device (often it can be absent). Sometimes the sixth character is also applied - this is an additional index (letters N, M or S), meaning the requirement of compliance with special standards. In the Japanese system, the color marking of transistors is not applied.

SMD elements

The marking of SMD-transistors is only symbolic. Due to the miniature sizes of these elements, the color coding is not used. A single encryption standard does not exist for them. Each manufacturer uses its own symbols. The alphanumeric code in this case can contain from one to three letters or digits. Each plant produces its own labeling tables for semiconductor elements.