Transistor KT315.Characteristics, marking and datasheet

The most popular Soviet low-power silicon n-p-n transistor, which is probably known to every amateur radio operator and which can be found in most old consumer electronics, is the KT315 transistor.The transistor began its history in 1967 and more than 7 billion pieces were manufactured in total, such popularity is due to the characteristics of the device.The transistor was used in radios, televisions, amplifiers and other equipment.It was manufactured using epitaxial-planar technology.

                                                                       The main characteristics of the transistor:

  • Collector-emitter voltage KT315A -25V
                                                                    kt315b -20V
                                                                    kt315v,d -40V
                                                                    kt315g,e -35V
                                                                    kt315j -15V
                                                                    kt315i -60V
    Collector current KT315A,B,V,G,D,E -100mA KT315J,I-50mA
    Current transfer coefficient h21e kt315a,V,D 20-90
                                                                      kt315b,g,e 50-350
                                                                      kt315j 30-250
                                                                      kt315i 30
    The limit frequency is 250 MHz
    Emitter-base voltage 6V
    Reverse collector current 1ma
    Dissipated power KT315A,B,C,g,D,e -150mW KT315J,I-100mW

In the photo, the low-frequency amplifier board.As you can see, there are at least 8 kt315 transistors on the board, there are about 15 of them completely in the device, that was the popularity of the transistor.Today, in this recognizable case, the transistor is probably no longer produced, although there may be a release in the TO-92 case.

The tester shows the following characteristics of the transistor:the current transfer coefficient is 165,with a collector current of 1.5mA

The kt315 transistor has a double, this is the p-n-p transistor kt361 and both of them make up a complementary pair.The KT361 has exactly the same housing and pin location, but the conductivity is different.It differs from the KT315 by the inscription on the case.If there is a bold dot near the letter or on the sides along the line, then this is kt361.Even in the black case, there may be a dual KVS varicap.

Notes on the transistor.In rare cases, they may be unreliable.This may be manifested by the fact that when the transistor is heated, it can go into a break, and when it cools down, it will work normally again.This is not a low-noise transistor, because of the plastic case it has sensitivity to light!,is also very sensitive to temperature.