Silicon transistor KT315. BC847 domestic analogue - KT315 transistor. Marking of transistors KT315 and KT361

Silicon epitaxial-planar n-p-n transistors type KT315 and KT315-1 (complementary pair). Designed for use in amplifiers of high, intermediate and low frequencies, directly used in radio-electronic equipment manufactured for civilian equipment and for export. Transistors KT315 and KT315-1 are produced in a plastic case with flexible leads. The KT315 transistor is manufactured in the KT-13 package. Subsequently, KT315 began to be produced in the KT-26 package (a foreign analogue of TO92), transistors in this package received an additional “1” in the designation, for example KT315G1. The housing reliably protects the transistor crystal from mechanical and chemical damage. Transistors KT315H and KT315N1 are intended for use in color television. Transistors KT315P and KT315R1 are intended for use in the “Electronics - VM” video recorder. Transistors are manufactured in the UHL climatic design and in a single design, suitable for both manual and automated assembly of equipment.

KT315 was produced by the following enterprises: "Electropribor" in Fryazino, "Kvazar" in Kiev, "Continent" in Zelenodolsk, "Kvartsit" in Ordzhonikidze, PA "Elkor" Republic of Kabardino-Balkaria, Nalchik, NIIPP Tomsk, PA "Electronics" Voronezh, in 1970 their production was also transferred to Poland to the Unitra CEMI enterprise.

As a result of negotiations in 1970, the Voronezh Association "Electronics" in terms of cooperation transferred the production of KT315 transistors to Poland. To do this, the workshop in Voronezh was completely dismantled, and in the shortest possible time, together with a supply of materials and components, it was transported, installed and launched in Warsaw. This electronics research and production center, established in 1970, was a semiconductor manufacturer in Poland. Unitra CEMI eventually went bankrupt in 1990, leaving the Polish microelectronics market open to foreign companies. Website of the Unitra CEMI enterprise museum: http://cemi.cba.pl/. By the end of the USSR, the total number of KT315 transistors produced exceeded 7 billion.

The KT315 transistor is produced to this day by a number of enterprises: CJSC Kremniy, Bryansk, SKB Elkor, Republic of Kabardino-Balkaria, Nalchik, NIIPP plant, Tomsk. The KT315-1 transistor is produced by: Kremniy JSC, Bryansk, Transistor plant, Republic of Belarus, Minsk, Eleks JSC, Aleksandrov, Vladimir region.

An example of the designation of KT315 transistors when ordering and in the design documentation of other products: “Transistor KT315A ZhK.365.200 TU/05”, for transistors KT315-1: “Transistor KT315A1 ZhK.365.200 TU/02”.

Brief technical characteristics of transistors KT315 and KT315-1 are presented in Table 1.

Table 1 - Brief technical characteristics of transistors KT315 and KT315-1

Type	Structure	P K max, P K* t. max, mW	f gr, MHz	U KBO max, U KER*max , IN	U EBO max, IN	I K max, mA	I KBO, µA	h 21e, h 21E*	C K, pF	r CE us, Ohm	r b, Ohm	τ to, ps
KT315A1	n-p-n	150	≥250	25	6	100	≤0,5	20...90 (10 V; 1 mA)	≤7	≤20	≤40	≤300
KT315B1	n-p-n	150	≥250	20	6	100	≤0,5	50...350 (10 V; 1 mA)	≤7	≤20	≤40	≤300
KT315B1	n-p-n	150	≥250	40	6	100	≤0,5	20...90 (10 V; 1 mA)	≤7	≤20	≤40	≤300
KT315G1	n-p-n	150	≥250	35	6	100	≤0,5	50...350 (10 V; 1 mA)	≤7	≤20	≤40	≤300
KT315D1	n-p-n	150	≥250	40	6	100	≤0,5	20...90 (10 V; 1 mA)	≤7	≤20	≤40	≤300
KT315E1	n-p-n	150	≥250	35	6	100	≤0,5	20...90 (10 V; 1 mA)	≤7	≤20	≤40	≤300
KT315Zh1	n-p-n	100	≥250	15	6	100	≤0,5	30...250 (10 V; 1 mA)	≤7	≤20	≤40	≤300
KT315I1	n-p-n	100	≥250	60	6	100	≤0,5	30 (10 V; 1 mA)	≤7	≤20	≤40	≤300
KT315N1	n-p-n	150	≥250	20	6	100	≤0,5	50...350 (10 V; 1 mA)	≤7	–	–	–
KT315Р1	n-p-n	150	≥250	35	6	100	≤0,5	150...350 (10 V; 1 mA)	≤7	–	–	–
KT315A	n-p-n	150 (250*)	≥250	25	6	100	≤0,5	30...120* (10 V; 1 mA)	≤7	≤20	≤40	≤300
KT315B	n-p-n	150 (250*)	≥250	20	6	100	≤0,5	50...350* (10 V; 1 mA)	≤7	≤20	≤40	≤500
KT315V	n-p-n	150 (250*)	≥250	40	6	100	≤0,5	30...120* (10 V; 1 mA)	≤7	≤20	≤40	≤500
KT315G	n-p-n	150 (250*)	≥250	35	6	100	≤0,5	50...350* (10 V; 1 mA)	≤7	≤20	≤40	≤500
KT315D	n-p-n	150 (250*)	≥250	40* (10k)	6	100	≤0,6	20...90 (10 V; 1 mA)	≤7	≤30	≤40	≤1000
KT315E	n-p-n	150 (250*)	≥250	35* (10k)	6	100	≤0,6	50...350* (10 V; 1 mA)	≤7	≤30	≤40	≤1000
KT315ZH	n-p-n	100	≥250	20* (10k)	6	50	≤0,6	30...250* (10 V; 1 mA)	≤7	≤25	–	≤800
KT315I	n-p-n	100	≥250	60* (10k)	6	50	≤0,6	≥30* (10 V; 1 mA)	≤7	≤45	–	≤950
KT315N	n-p-n	150	≥250	35* (10k)	6	100	≤0,6	50...350* (10 V; 1 mA)	≤7	≤5,5	–	≤1000
KT315R	n-p-n	150	≥250	35* (10k)	6	100	≤0,5	150...350* (10 V; 1 mA)	≤7	≤20	–	≤500

Note:
1. I KBO – reverse collector current – current through the collector junction at a given reverse collector-base voltage and open emitter terminal, measured at U KB = 10 V;
2. I K max – maximum permissible direct collector current;
3. U KBO max – collector-base breakdown voltage at a given reverse collector current and an open emitter circuit;
4. U EBO max – emitter-base breakdown voltage at a given emitter reverse current and open collector circuit;
5. U KER max – collector-emitter breakdown voltage at a given collector current and a given (final) resistance in the base-emitter circuit;
6. R K.t max – constant dissipated power of the collector with a heat sink;
7. P K max – maximum permissible constant power dissipation of the collector;
8. r b – base resistance;
9. r KE us – saturation resistance between collector and emitter;
10. C K – collector junction capacitance, measured at U K = 10 V;
11. f gp – cutoff frequency of the transistor current transfer coefficient for a common emitter circuit;
12. h 2lе – transistor voltage feedback coefficient in low-signal mode for circuits with a common emitter and a common base, respectively;
13. h 2lЭ – for a circuit with a common emitter in large signal mode;
14. τ к – time constant of the feedback circuit at high frequency.

Dimensions of transistor KT315

Transistor housing type KT-13. The mass of one transistor is no more than 0.2 g. The tensile force is 5 N (0.5 kgf). The minimum distance between the lead bend and the housing is 1 mm (indicated as L1 in the figure). Soldering temperature (235 ± 5) °C, distance from the body to the soldering point 1 mm, soldering duration (2 ± 0.5) s. Transistors must withstand the heat generated at the soldering temperature (260 ± 5) °C for 4 seconds. The leads must remain solderable for 12 months from the date of manufacture, subject to the soldering modes and rules specified in the “Operating Instructions” section. Transistors are resistant to alcohol-gasoline mixture (1:1). KT315 transistors are fireproof. The overall dimensions of the KT315 transistor are shown in Figure 1.

Figure 1 – Marking, pinout and overall dimensions of the KT315 transistor

Dimensions of transistor KT315-1

Transistor housing type KT-26. The weight of one transistor is no more than 0.3 g. The minimum distance of the lead bend from the body is 2 mm (indicated as L1 in the figure). Soldering temperature (235 ± 5) °C, distance from the body to the soldering point is at least 2 mm, soldering duration (2 ± 0.5) s. KT315-1 transistors are fireproof. The overall dimensions of the KT315-1 transistor are shown in Figure 2.

Figure 2 – Marking, pinout and overall dimensions of the KT315-1 transistor

Transistor pinout

If you place the KT315 transistor with the markings facing away from you (as shown in Figure 1) with the terminals down, then the left terminal is the base, the central one is the collector, and the right one is the emitter.

If you place the KT315-1 transistor on the contrary with the markings facing you (as shown in Figure 2) with the terminals also down, then the left terminal is the emitter, the central one is the collector, and the right one is the base.

Transistor markings

Transistor KT315. The type of transistor is indicated on the label, and the group is also indicated on the device body in the form of a letter. The case indicates the full name of the transistor or just a letter, which is shifted to the left edge of the case. The plant's trademark may not be indicated. The date of issue is indicated in a digital or coded designation (only the year of issue can be indicated). The dot in the transistor marking indicates its application - as part of color television. Old (manufactured before 1971) KT315 transistors were marked with a letter in the middle of the case. At the same time, the first issues were marked with only one capital letter, and around 1971 they switched to the usual two-line letter. An example of the marking of the KT315 transistor is shown in Figure 1. It should also be noted that the KT315 transistor was the first mass-produced transistor with code marking in a miniature plastic package KT-13. The vast majority of transistors KT315 and KT361 (the characteristics are the same as those of the KT315, and the conductivity is p-n-p) were produced in yellow or red-orange colors; transistors in pink, green and black colors are much less common. The marking of transistors intended for sale, in addition to the letter designating the group, the plant’s trademark and the date of manufacture, also included a retail price, for example “ts20k”, which meant the price of 20 kopecks.

Transistor KT315-1. The type of transistor is also indicated on the label, and the full name of the transistor is indicated on the case, and transistors can also be marked with a code sign. An example of the marking of the KT315-1 transistor is shown in Figure 2. The marking of the transistor with a code sign is given in Table 2.

Table 2 - Marking of the KT315-1 transistor with a code sign

Transistor type	Marking mark on the cut side surface of the body	Marking mark at the end of the body
KT315A1	Green triangle	Red dot
KT315B1	Green triangle	Yellow dot
KT315B1	Green triangle	Green dot
KT315G1	Green triangle	Blue dot
KT315D1	Green triangle	Blue dot
KT315E1	Green triangle	White dot
KT315Zh1	Green triangle	Two red dots
KT315I1	Green triangle	Two yellow dots
KT315N1	Green triangle	Two green dots
KT315Р1	Green triangle	Two blue dots

Instructions for the use and operation of transistors

The main purpose of transistors is to work in amplifier stages and other circuits of electronic equipment. It is allowed to use transistors manufactured in a normal climatic design in equipment intended for operation in all climatic conditions, when the transistors are coated directly in the equipment with varnishes (in 3 - 4 layers) of type UR-231 according to TU 6-21-14 or EP-730 according to GOST 20824 with subsequent drying. The permissible value of the static potential is 500 V. The minimum permissible distance from the case to the place of tinning and soldering (along the lead length) is 1 mm for the KT315 transistor and 2 mm for the KT315-1 transistor. The number of permissible re-solderings of terminals during installation (assembly) operations is one.

External influencing factors

Mechanical impacts according to group 2, table 1 in GOST 11630, including:
– sinusoidal vibration;
– frequency range 1-2000 Hz;
– acceleration amplitude 100 m/s 2 (10g);
– linear acceleration 1000 m/s 2 (100g).

Climatic influences - according to GOST 11630, including: increased operating temperature of the environment 100 ° C; reduced operating temperature of the environment minus 60 °C; change in ambient temperature from minus 60 to 100 °C. For KT315-1 transistors, the temperature of the environment changes from minus 45 to 100 °C

Transistor reliability

The failure rate of transistors during operating time is more than 3×10 -7 1/h. Transistor operating time tn = 50,000 hours. 98% shelf life of transistors is 12 years. The packaging must protect transistors from static electricity charges.

Foreign analogues of the KT315 transistor

Foreign analogues of the KT315 transistor are shown in Table 3. Technical information (datasheet) for foreign analogues of the KT315 transistor can also be downloaded in the table below. The prices below correspond to the status as of 08.2018.

Table 3 - Foreign analogues of the KT315 transistor

Domestic transistor	Opportunity buy	Company manufacturer	A country manufacturer
KT315A	No	Unitra CEMI	Poland
KT315B	No	Unitra CEMI	Poland
KT315V	No	Unitra CEMI	Poland
KT315G	No	Unitra CEMI	Poland
KT315D	There is	Hitachi	Japan
KT315E	there is ~ 4$	Central Semiconductor	USA
KT315ZH	available ~ 9$	Sprague electric corp.	USA
KT315ZH	There is	ITT Intermetall GmbH	Germany
KT315I	available ~ 16$	New Jersey Semiconductor	USA
KT315I	There is	Sony	Japan
KT315N	there is ~1$	Sony	Japan
KT315R	No	Unitra CEMI	Poland

The foreign prototype of the KT315-1 transistor is the transistors 2SC544, 2SC545, 2SC546, manufactured by Sanyo Electric, produced in Japan. Transistors 2SC545, 2SC546 can also be purchased, the estimated price is about $6.

Main technical characteristics

The main electrical parameters of KT315 transistors upon acceptance and delivery are shown in Table 4. The maximum permissible operating modes of the transistor are given in Table 5. The current-voltage characteristics of KT315 transistors are shown in Figures 3 - 8. The dependences of the electrical parameters of KT315 transistors on the modes and conditions of their operation are presented in Figures 9 – 19.

Table 4 – Electrical parameters of KT315 transistors upon acceptance and delivery

Parameter name (measurement mode) units	Literal designation	Norm parameter		Temperature, °C
		no less	no more
Boundary voltage (IC =10 mA), V KT315A, KT315B, KT315ZH, KT315N KT315V, KT315D, KT315I KT315G, KT315E, KT315R	U (CEO)	15 30 25	–	25
(IC =20 mA, I B =2 mA), V KT315A, KT315B, KT315V, KT315G, KT315R KT315D, KT315E KT315ZH KT315I	U CEsat	–	0,4 0,6 0,5 0,9
Collector-emitter saturation voltage (IC =70 mA, I B =3.5 mA), V KT315N	U CEsat	–	0,4
Base-emitter saturation voltage (IC =20 mA, I B =2 mA), V KT315A, KT315B, KT315V, KT315G, KT315N, KTZ I5P KT315D, KT315E KT315ZH KT315I	UBEsat	–	1,0 1,1 0,9 1,35
KT315A, KT315B, KT315V, KT315G, KT315N, KT315R KT315D, KT315E, KT315Zh, KG315I	I CBO	–	0,5 0,6	25, -60
Reverse collector current (U CB =10 V), µA KT3I5A KT315B, KT315V, KT315G, KT315N, KT315R KT315D, KT315E	I CBO	–	10 15	100
Reverse emitter current (U EB =5 V) µA KT315A – KG315E, KT315ZH, XT315N KT315I KT315R	I EBO	–	30 50 3	25
, (R BE =10 kOhm U CE =25 V), mA, KT3I5A (R BE =10 kOhm U CE =20 V), mA, KT315B, KT315N (R BE =10 kOhm U CE =40 V), mA KT315V (R BE =10 kOhm U CE =35 V), mA, KT315G (R BE =10 kOhm U CE =40 V), mA, KT315D (R BE =10 kOhm U CE =35 V), mA, KT315E	I CER	–	0,6 0,6 0,6 0,6 1,0 1,0 0,005	25
Reverse current collector-emitter (R BE =10 kOhm U CE =35 V), mA, KT315R	I CER	–	0,01	100
Reverse current collector-emitter (U CE =20 V), mA, KT315Zh (U CE =60 V), mA, KT315I	I CES	–	0,01 0,1	25, -60
Reverse current collector-emitter (U CE =20 V), mA, KT3I5Zh (U CE =60 V), mA, KT3I5I	I CES	–	0,1 0,2	100
Static current transfer coefficient (U CB = 10 V, I E = 1 mA) KT315A, KT3I5B KT315D KT315ZH KT315I KT315R	h 21E	30 50 20 30 30 150	120 350 90 250 – 350	25
Static current transfer coefficient (U CB = 10 V, I E = 1 mA) KT315A, KT3I5B KTZ15B, KT315G, KT315E, KT315N KT315D KT315ZH KT315I KT315R	h 21E	30 50 20 30 30 150	250 700 250 400 – 700	100
Static current transfer coefficient (U CB = 10 V, I E = 1 mA) KT315A, KT3I5B KTZ15B, KT315G, KT315E, KT315N KT315D KT315ZH KT315I KT315R	h 21E	5 15 5 5 5 70	120 350 90 250 – 350	-60
Current transfer coefficient module at high frequency (U CB = 10 V, I E = 5 mA, f = 100 MHz)	\|h 21E \|	2,5	–	25
Collector junction capacitance (UCB = 10 V, f = 10 MHz), pF	C C	–	7	25

Table 5 – Maximum permissible operating modes of the KT315 transistor

Parameter, unit	Designation	Parameter norm
		KG315A	KG315B	KG315V	KG315G	KTZ15D	KG315E	KG315ZH	KG315I	KT315N	KT315R
Max. permissible DC collector-emitter voltage, (R BE = 10 kOhm), V 1)	U CERmax	25	20	40	35	40	35	–	–	20	35
Max. permissible constant collector-emitter voltage during a short circuit in the emitter-base circuit, V 1)	U CES max	–	–	–	–	–	–	20	60	–	–
Max. permissible DC collector-base voltage, V 1)	U CB max	25	20	40	35	40	35	–	–	20	35
Max. permissible constant emitter-base voltage, V 1)	U EB max	6	6	6	6	6	6	6	6	6	6
Max. permissible direct collector current, mA 1)	I C max	100	100	100	100	100	100	100	100	100	100
Max. permissible constant dissipated power of the collector, mW 2)	P C max	200	200	200	200	200	200	200	200	200	200
Max. permissible transition temperature, ⁰С	t j max	125	125	125	125	125	125	125	125	125	125

Note:
1. For the entire operating temperature range.
2. At t atv from minus 60 to 25 °C. When the temperature rises above 25 °C, P C max is calculated by the formula:

where R t hjα is the total thermal resistance of the junction-environment, equal to 0.5 °C/mW.

Figure 3 – Typical input characteristics of transistors KT315A – KT315I, KT315N, KT315R

Figure 4 – Typical input characteristics of transistors KT315A – KT315I, KT315N, KT315R
at U CE = 0, t atv = (25±10) °С

Figure 5 – Typical output characteristics of transistors of types KT315A, KT315V, KT315D, KT315I
at t atb = (25±10) °C

Figure 6 – Typical output characteristics of transistors of types KT315B, KT315G, KT315E, KT315N
at t atb = (25±10) °C

Figure 7 – Typical output characteristics
transistor KT315Zh at t atv = (25±10) °C

Figure 8 – Typical output characteristics
transistor KT315R at t atv = (25±10) °C

Figure 9 – Dependence of collector-emitter saturation voltage on direct collector current for transistors of type KT315A - KT315I, KT315N, KT315R at I C / I B = 10,
t atb = (25±10) °С

Figure 10 – Dependence of base-emitter saturation voltage on direct collector current for transistors of type KT315A – KT315I, KT315N, KT315R at I C /I B = 10, t atv = (25±10) °C

Figure 11 – Dependence of the static current transfer coefficient on the emitter direct current for transistors KT315A, KT315V, KT315D, KT315I at U CB = 10,
t atb = (25±10) °С

Figure 12 – Dependence of the static current transfer coefficient on the emitter direct current for transistors KT315B, KT315G, KT315E, KT315N at U CB = 10,
t atb = (25±10) °С

Figure 13 – Dependence of the static current transfer coefficient on the emitter direct current for the KT315Zh transistor at U CB = 10, t atv = (25±10) °C

Figure 14 – Dependence of the static current transfer coefficient on the emitter direct current for the KT315R transistor at U CB = 10, t atv = (25±10) °C

Figure 15 – Dependence of the modulus of the current transfer coefficient at high frequency on the direct current of the emitter at U CB = 10, f = 100 MHz, t atv = (25±10) °C

Figure 16 – Dependence of the time constant of the feedback circuit at high frequency on the collector-base voltage at I E = 5 mA, t atv = (25 ± 10) ° C for KT315A

Figure 17 – Dependence of the time constant of the feedback circuit at high frequency on the collector-base voltage at I E = 5 mA, t atv = (25±10) °C for KT315E, KT315V, KT315G, KT315N, KT315R

Figure 18 – Dependence of the time constant of the feedback circuit at high frequency on the emitter current at U CB = 10 V, f = 5 MHz, t atv = (25±10) °C for
KT315A

Perhaps there is no more or less complex electronic device produced in the USSR during the seventies, eighties and nineties, in the circuit of which the KT315 transistor would not be used. He has not lost popularity to this day.

The designation uses the letter K, meaning “silicon,” like most semiconductor devices manufactured since that time. The number “3” means that the KT315 transistor belongs to the group of low-power broadband devices.

The plastic case did not imply high power, but was cheap.

The KT315 transistor was produced in two versions, flat (orange or yellow) and cylindrical (black).

In order to make it more convenient to determine how to mount it, there is a bevel on its “front” side in the flat version, the collector is in the middle, the base is on the left, the collector is on the right.

The black transistor had a flat cut; if you position the transistor towards you, the emitter would be on the right, the collector on the left, and the base in the middle.

The marking consisted of a letter, depending on the permissible supply voltage, from 15 to 60 Volts. The power also depends on the letter; it can reach 150 mW, and this is with microscopic dimensions for those times - width - seven, height - six, and thickness - less than three millimeters.

The KT315 transistor is high-frequency, this explains the breadth of its application. up to 250 MHz guarantees its stable operation in radio circuits of receivers and transmitters, as well as range amplifiers.

Conductivity - reverse, n-p-n. For a pair using a push-pull amplification circuit, KT361 was created, with direct conduction. Outwardly, these “twin brothers” are practically no different, only the presence of two black marks indicates p-n-p conductivity. Another marking option, the letter is located exactly in the middle of the case, and not on the edge.

With all its advantages, the KT315 transistor also has a disadvantage. Its leads are flat, thin, and break off very easily, so installation should be done very carefully. However, even having damaged the part, many radio amateurs managed to fix it by filing the body a little and “sucking” the wire, although this was difficult and there was no particular point.

The case is so unique that it clearly indicates the Soviet origin of the KT315. You can find an analogue, for example, BC546V or 2N9014 - from imports, KT503, KT342 or KT3102 - from our transistors, but record low prices make such tricks meaningless.

Billions of KT315 have been produced, and although in our time there are microcircuits in which dozens and hundreds of such semiconductor devices are built-in, sometimes they are still used to assemble simple auxiliary circuits.

Even though I’m late for Radio Day, I’ll still write about KT315. This transistor has been seen and soldered by many, but today we will see how the KT315 produced in different years differs, what its design is, and we will compare its design with modern foreign analogues.

About production

KT315 is the first transistor produced according to the latest fashion of the late 60s - it is a planar epitaxial transistor, i.e. the collector, emitter and base are manufactured sequentially on one silicon wafer: a silicon wafer is taken, doped to type n (this will be the collector), then doped to a certain depth to type p (this will be the base), and then doped again to a smaller depth on top depth of type n (this will be the emitter). Next, the plate needs to be cut into pieces and packaged in a plastic case.

This manufacturing process was much cheaper than alloy technology, and made it possible to obtain previously unimaginable transistor parameters (in particular, an operating frequency of 250-300 MHz).

The next novelty, which led to cheaper production, was mounting the crystal not in a metal case, but on a metal strip with leads: a crystal, on the lower side of which the collector was soldered to the central terminal, and the base and emitter were connected with a welded wire. Then all this was filled with plastic, the excess parts of the tape were cut off - and the KT315 was obtained the way we are used to seeing it.

Explanations for the figure on the right: a - scribing and dividing the plate into crystals with ready-made structures; b - soldering of crystals to the tape; c - connection of the output; g - cutting the tape; d - sealing; e - removal from the mold; g - cutting the tape and separating diodes/transistors; 1 - tape; 2 - crystal; 3 - crystal output

Serial production began in 1967-1968, for mere mortals the price at first was 4 rubles per transistor. But already in the mid-70s it dropped to 15-20 kopecks, which made it a truly affordable transistor. With an engineer's salary of 120 rubles, it was possible to buy 600 transistors per month. By the way, now for an engineer’s conditional salary of 45 thousand rubles you can buy 121,000 BC856B transistors, so the engineer’s transistor standard of living has increased 201 times

It is noteworthy that the first devices assembled on the KT315 were transistor (microcircuits were just gaining momentum) “calculators” Elektronika DD and Elektronika 68.

This is the collection I found:

Those without a manufacturer's sign are KT361, pnp option. The rest, with the logo - KT315 (even if the “letter is in the center”). It is noteworthy that in times of a planned economy, fixed prices, and a formal absence of speculation, the price was sometimes written directly on transistors.

What's inside?

The oldest transistor I found is KT315A, released in March 1978.
We see that the crystal is not broken off from the plate perfectly; there is a lot of unused space around the transistor.

Here the crystal itself is a collector, in the center, if I’m not mistaken, there are circles of the base, and around it there is a wider “belt” of the emitter. The base seems to dive under the emitter and comes out on the back side of the ring.

Here you can immediately see that the space is spent much more economically, the crystal is cut almost perfectly, small non-critical photolithography defects are noticeable, apparently contact photolithography is still used here. However, for transistors this is quite enough.

Comparison

If we compare it in scale with the modern NXP BC847B transistor, we can see that the size was reduced by another factor of 2 due to “squaring”, but the transistor itself did not fundamentally change - the same collector at the “bottom” of the crystal, and the emitter and base leads welded with wire.

It is noteworthy that the width/height of the BC847 crystal is almost equal to the thickness of the wafer; it is practically a silicon cube, not a wafer. It is difficult to reduce the area further, at least without further thinning the plate (thinning of the plate - spelled correctly).

Future

Is KT315 dead? Definitely not. Until now, for example, it is in the price lists of Integral at 248 Belarusian rubles (~1 Russian ruble), i.e. probably still in production. Of course, with the development of automatic assembly of printed circuit boards, it had to give way to SMD options, for example KT3129 and KT3130 and many others, including foreign analogues BC846-BC848, BC856-BC858.

15.04.2018

Silicon epitaxial-planar n-p-n transistors type KT315 and KT315-1. Designed for use in high, intermediate and low frequency amplifiers, directly used in electronic equipment manufactured for civilian use and for export. Transistors KT315 and KT315-1 are produced in a plastic case with flexible leads. The KT315 transistor is manufactured in the KT-13 package. Subsequently, KT315 began to be produced in the KT-26 package (a foreign analogue of TO92), transistors in this package received an additional “1” in the designation, for example KT315G1. The housing reliably protects the transistor crystal from mechanical and chemical damage. Transistors KT3I5H and KT315N1 are intended for use in color television. Transistors KT315P and KT315R1 are intended for use in the “Electronics - VM” video recorder. Transistors are manufactured in the UHL climatic design and in a single design, suitable for both manual and automated assembly of equipment.

The KT315 transistor was produced by the following enterprises: Elektropribor, Fryazino, Kvazar, Kiev, Continent, Zelenodolsk, Quartzite, Ordzhonikidze, Elkor Production Association, Republic of Kabardino-Balkaria, Nalchik, NIIPP, Tomsk, PO "Electronics" Voronezh, in 1970 their production was also transferred to Poland to the Unitra CEMI enterprise.

Brief technical characteristics of transistors KT315 and KT315-1 are presented in Table 1.

Table 1 - Brief technical characteristics of transistors KT315 and KT315-1

Type	Structure	P K max, P K* t. max, mW	f gr, MHz	U KBO max, U KER*max , IN	U EBO max, IN	I K max, mA	I KBO, µA	h 21e, h 21E*	C K, pF	r CE us, Ohm	r b, Ohm	τ to, ps
KT315A1	n-p-n	150	≥250	25	6	100	≤0,5	20...90 (10 V; 1 mA)	≤7	≤20	≤40	≤300
KT315B1	n-p-n	150	≥250	20	6	100	≤0,5	50...350 (10 V; 1 mA)	≤7	≤20	≤40	≤300
KT315B1	n-p-n	150	≥250	40	6	100	≤0,5	20...90 (10 V; 1 mA)	≤7	≤20	≤40	≤300
KT315G1	n-p-n	150	≥250	35	6	100	≤0,5	50...350 (10 V; 1 mA)	≤7	≤20	≤40	≤300
KT315D1	n-p-n	150	≥250	40	6	100	≤0,5	20...90 (10 V; 1 mA)	≤7	≤20	≤40	≤300
KT315E1	n-p-n	150	≥250	35	6	100	≤0,5	20...90 (10 V; 1 mA)	≤7	≤20	≤40	≤300
KT315Zh1	n-p-n	100	≥250	15	6	100	≤0,5	30...250 (10 V; 1 mA)	≤7	≤20	≤40	≤300
KT315I1	n-p-n	100	≥250	60	6	100	≤0,5	30 (10 V; 1 mA)	≤7	≤20	≤40	≤300
KT315N1	n-p-n	150	≥250	20	6	100	≤0,5	50...350 (10 V; 1 mA)	≤7	–	–	–
KT315Р1	n-p-n	150	≥250	35	6	100	≤0,5	150...350 (10 V; 1 mA)	≤7	–	–	–
KT315A	n-p-n	150 (250*)	≥250	25	6	100	≤0,5	30...120* (10 V; 1 mA)	≤7	≤20	≤40	≤300
KT315B	n-p-n	150 (250*)	≥250	20	6	100	≤0,5	50...350* (10 V; 1 mA)	≤7	≤20	≤40	≤500
KT315V	n-p-n	150 (250*)	≥250	40	6	100	≤0,5	30...120* (10 V; 1 mA)	≤7	≤20	≤40	≤500
KT315G	n-p-n	150 (250*)	≥250	35	6	100	≤0,5	50...350* (10 V; 1 mA)	≤7	≤20	≤40	≤500
KT315D	n-p-n	150 (250*)	≥250	40* (10k)	6	100	≤0,6	20...90 (10 V; 1 mA)	≤7	≤30	≤40	≤1000
KT315E	n-p-n	150 (250*)	≥250	35* (10k)	6	100	≤0,6	50...350* (10 V; 1 mA)	≤7	≤30	≤40	≤1000
KT315ZH	n-p-n	100	≥250	20* (10k)	6	50	≤0,6	30...250* (10 V; 1 mA)	≤7	≤25	–	≤800
KT315I	n-p-n	100	≥250	60* (10k)	6	50	≤0,6	≥30* (10 V; 1 mA)	≤7	≤45	–	≤950
KT315N	n-p-n	150	≥250	35* (10k)	6	100	≤0,6	50...350* (10 V; 1 mA)	≤7	≤5,5	–	≤1000
KT315R	n-p-n	150	≥250	35* (10k)	6	100	≤0,5	150...350* (10 V; 1 mA)	≤7	≤20	–	≤500

Dimensions of transistor KT315

Figure 1 – Marking, pinout and overall dimensions of the KT315 transistor

Dimensions of transistor KT315-1

Figure 2 – Marking, pinout and overall dimensions of the KT315-1 transistor

Transistor pinout

Transistor markings

Table 2 - Marking of the KT315-1 transistor with a code sign

Transistor type	Marking mark on the cut side surface of the body	Marking mark at the end of the body
KT315A1	Green triangle	Red dot
KT315B1	Green triangle	Yellow dot
KT315B1	Green triangle	Green dot
KT315G1	Green triangle	Blue dot
KT315D1	Green triangle	Blue dot
KT315E1	Green triangle	White dot
KT315Zh1	Green triangle	Two red dots
KT315I1	Green triangle	Two yellow dots
KT315N1	Green triangle	Two green dots
KT315Р1	Green triangle	Two blue dots

Instructions for the use and operation of transistors

External influencing factors

Transistor reliability

Foreign analogues of the KT315 transistor

Foreign analogues of the KT315 transistor are shown in Table 3.

Table 3 - Foreign analogues of the KT315 transistor

Domestic transistor	Foreign analogue	Company manufacturer	A country manufacturer
KT315A	BFP719	Unitra CEMI	Poland
KT315B	BFP720	Unitra CEMI	Poland
KT315V	BFP721	Unitra CEMI	Poland
KT315G	BFP722	Unitra CEMI	Poland
KT315D	2SC641	Hitachi	Japan
KT315E	2N3397	Central Semiconductor	USA
KT315ZH	2N2711	Sprague electric corp.	USA
KT315ZH	BFY37, BFY37i	ITT Intermetall GmbH	Germany
KT315I	2SC634	New Jersey Semiconductor	USA
KT315I	2SC634	Sony	Japan
KT315N	2SC633	Sony	Japan
KT315R	BFP722	Unitra CEMI	Poland

The foreign prototype of the KT315-1 transistor is the transistors 2SC544, 2SC545, 2SC546, manufactured by Sanyo Electric, produced in Japan.

Main technical characteristics

Table 4 – Electrical parameters of KT315 transistors upon acceptance and delivery

Parameter name (measurement mode) units	Literal designation	Norm parameter		Temperature, °C
		no less	no more
Boundary voltage (IC =10 mA), V KT315A, KT315B, KT315ZH, KT315N KT315V, KT315D, KT315I KT315G, KT315E, KT315R	U (CEO)	15 30 25	–	25
(IC =20 mA, I B =2 mA), V KT315A, KT315B, KT315V, KT315G, KT315R KT315D, KT315E KT315ZH KT315I	U CEsat	–	0,4 0,6 0,5 0,9
Collector-emitter saturation voltage (IC =70 mA, I B =3.5 mA), V KT315N	U CEsat	–	0,4
Base-emitter saturation voltage (IC =20 mA, I B =2 mA), V KT315A, KT315B, KT315V, KT315G, KT315N, KTZ I5P KT315D, KT315E KT315ZH KT315I	UBEsat	–	1,0 1,1 0,9 1,35
KT315A, KT315B, KT315V, KT315G, KT315N, KT315R KT315D, KT315E, KT315Zh, KG315I	I CBO	–	0,5 0,6	25, -60
Reverse collector current (U CB =10 V), µA KT3I5A KT315B, KT315V, KT315G, KT315N, KT315R KT315D, KT315E	I CBO	–	10 15	100
Reverse emitter current (U EB =5 V) µA KT315A – KG315E, KT315ZH, XT315N KT315I KT315R	I EBO	–	30 50 3	25
, (R BE =10 kOhm U CE =25 V), mA, KT3I5A (R BE =10 kOhm U CE =20 V), mA, KT315B, KT315N (R BE =10 kOhm U CE =40 V), mA KT315V (R BE =10 kOhm U CE =35 V), mA, KT315G (R BE =10 kOhm U CE =40 V), mA, KT315D (R BE =10 kOhm U CE =35 V), mA, KT315E	I CER	–	0,6 0,6 0,6 0,6 1,0 1,0 0,005	25
(R BE =10 kOhm U CE =35 V), mA, KT315R	I CER	–	0,01	100
Reverse current collector-emitter (U CE =20 V), mA, KT315Zh (U CE =60 V), mA, KT315I	I CES	–	0,01 0,1	25, -60
Reverse current collector-emitter (U CE =20 V), mA, KT3I5Zh (U CE =60 V), mA, KT3I5I	I CES	–	0,1 0,2	100
(U CB = 10 V, I E = 1 mA) KT315A, KT3I5B KT315D KT315ZH KT315I KT315R	h 21E	30 50 20 30 30 150	120 350 90 250 – 350	25
Static current transfer coefficient (U CB = 10 V, I E = 1 mA) KT315A, KT3I5B KT315D KT315ZH KT315I KT315R	h 21E	30 50 20 30 30 150	250 700 250 400 – 700	100
Static current transfer coefficient (U CB = 10 V, I E = 1 mA) KT315A, KT3I5B KTZ15B, KT315G, KT315E, KT315N KT315D KT315ZH KT315I KT315R	h 21E	5 15 5 5 5 70	120 350 90 250 – 350	-60
Current transfer coefficient module at high frequency (U CB = 10 V, I E = 5 mA, f = 100 MHz)	\|h 21E \|	2,5	–	25
Collector junction capacitance (UCB = 10 V, f = 10 MHz), pF	C C	–	7	25

Table 5 – Maximum permissible operating modes of the KT315 transistor

Parameter, unit	Designation	Parameter norm
		KG315A	KG315B	KG315V	KG315G	KTZ15D	KG315E	KG315ZH	KG315I	KT315N	KT315R
Max. permissible DC collector-emitter voltage, (R BE = 10 kOhm), V 1)	U CERmax	25	20	40	35	40	35	–	–	20	35
Max. permissible constant collector-emitter voltage during a short circuit in the emitter-base circuit, V 1)	U CES max	–	–	–	–	–	–	20	60	–	–
Max. permissible DC collector-base voltage, V 1)	U CB max	25	20	40	35	40	35	–	–	20	35
Max. permissible constant emitter-base voltage, V 1)	U EB max	6	6	6	6	6	6	6	6	6	6
Max. permissible direct collector current, mA 1)	I C max	100	100	100	100	100	100	100	100	100	100
Max. permissible constant dissipated power of the collector, mW 2)	P C max	200	200	200	200	200	200	200	200	200	200
Max. permissible transition temperature, ⁰С	t j max	125	125	125	125	125	125	125	125	125	125

Note:
1. For the entire operating temperature range.
2. At t atv from minus 60 to 25 °C. When the temperature rises above 25 °C, P C max is calculated by the formula:

where R t hjα is the total thermal resistance of the junction-environment, equal to 0.5 °C/mW.

Figure 3 – Typical input characteristics of transistors KT315A – KT315I, KT315N, KT315R

Figure 4 – Typical input characteristics of transistors KT315A – KT315I, KT315N, KT315R
at U CE = 0, t atv = (25±10) °С

Figure 5 – Typical output characteristics of transistors of types KT315A, KT315V, KT315D, KT315I
at t atb = (25±10) °C

Figure 6 – Typical output characteristics of transistors of types KT315B, KT315G, KT315E, KT315N
at t atb = (25±10) °C

Figure 7 – Typical output characteristics
transistor KT315Zh at t atv = (25±10) °C

Figure 8 – Typical output characteristics
transistor KT315R at t atv = (25±10) °C

Figure 9 – Dependence of collector-emitter saturation voltage on direct collector current for transistors of type KT315A - KT315I, KT315N, KT315R at I C / I B = 10,
t atb = (25±10) °С

Figure 10 – Dependence of base-emitter saturation voltage on direct collector current for transistors of type KT315A – KT315I, KT315N, KT315R at I C /I B = 10, t atv = (25±10) °C

Figure 11 – Dependence of the static current transfer coefficient on the emitter direct current for transistors KT315A, KT315V, KT315D, KT315I at U CB = 10,
t atb = (25±10) °С

Figure 12 – Dependence of the static current transfer coefficient on the emitter direct current for transistors KT315B, KT315G, KT315E, KT315N at U CB = 10,
t atb = (25±10) °С

Figure 13 – Dependence of the static current transfer coefficient on the emitter direct current for the KT315Zh transistor at U CB = 10, t atv = (25±10) °C

Figure 14 – Dependence of the static current transfer coefficient on the emitter direct current for the KT315R transistor at U CB = 10, t atv = (25±10) °C

Figure 15 – Dependence of the modulus of the current transfer coefficient at high frequency on the direct current of the emitter at U CB = 10, f = 100 MHz, t atv = (25±10) °C

Figure 16 – Dependence of the time constant of the feedback circuit at high frequency on the collector-base voltage at I E = 5 mA, t atv = (25 ± 10) ° C for KT315A

Figure 17 – Dependence of the time constant of the feedback circuit at high frequency on the collector-base voltage at I E = 5 mA, t atv = (25±10) °C for KT315E, KT315V, KT315G, KT315N, KT315R

Figure 18 – Dependence of the time constant of the feedback circuit at high frequency on the emitter current at U CB = 10 V, f = 5 MHz, t atv = (25±10) °C for
KT315A

This is a real legend in the world of radio electronics! The KT315 transistor was developed in the Soviet Union and for decades held the palm among similar technologies. Why did he deserve such recognition?

Transistor KT315

What can you say about this legend? KT315 is a low-power silicon high-frequency bipolar transistor. It has n-p-n conductivity. It is manufactured in the KT-13 housing. Due to its versatility, it became widely used in Soviet-made radio-electronic equipment. What analogue of the KT315 transistor exists? There are quite a few of them: BC847B, BFP722, 2SC634, 2SC641, 2SC380, 2SC388, BC546, KT3102.

Development

The idea of creating such a device first appeared among Soviet scientists and engineers in 1966. Since it was created in order to subsequently put it into mass production, the development of both the transistor itself and the equipment for its production was entrusted to the Pulsar Research Institute, the Fryazino Semiconductor Plant and the Design Bureau located on its territory. In 1967, active preparations and creation of conditions were underway. And in 1968, they released the first electronic devices, which are now known as the KT315 transistor. It became the first mass-produced device of this kind. The marking of KT315 transistors is as follows: initially, a letter was placed in the upper left corner of the flat side, which designated the group. Sometimes the date of manufacture was also indicated. A few years later, in the same building, they began producing complementary KT361 transistors with pnp conductivity. To distinguish them, a mark was placed in the middle of the upper part. For the development of the KT315 transistor, the USSR State Prize was awarded in 1973.

Technology

When the KT315 transistor began to be produced, a new technology was tested at the same time - planar epitaxial. It implies that all device structures are created on one side. What requirements does the KT315 transistor have? The parameters of the source material must have a conductivity type similar to that of the collector. And first, the base region is formed, and only then the emitter region. This technology was a very important milestone in the development of the Soviet radio-electronic industry, as it allowed us to get closer to the production of integrated circuits without the use of a dielectric substrate. Until this device appeared, low-frequency devices were manufactured using the alloy method, and high-frequency ones - according to the diffusion method.

We can confidently say that the parameters that the completed device had were a real breakthrough for its time. Why do they say this about the KT315 transistor? The parameters are why they said so much about him! So, if we compare it with the contemporary germanium high-frequency transistor GT308, then it exceeds it in power by 1.5 times. The cutoff frequency is more than 2 times, and the maximum collector current is generally 3. And at the same time, the KT315 transistor was much cheaper. It was also able to replace the low-frequency MP37, because with equal power it had a higher base current transfer coefficient. Also, the best performance was in the maximum pulse current, and KT315 had superior temperature stability. Thanks to the use of silicon, this transistor could operate at a moderate current for tens of minutes, even if the solder around it was at the melting point. True, working in such conditions slightly deteriorated the characteristics of the device, but it did not fail irreversibly.

Applications and complementary technologies

The KT315 transistor has found wide application in audio, intermediate and high-frequency amplifier circuits. An important addition was the development of complementary KT361. Together they have found their application in transformerless push-pull circuits.

Conclusion

At one time, this device played a big role in the construction of various circuits. It even got to the point that in stores for radio amateurs during the Soviet Union, they were sold not by piece, but by weight. This was both an indicator of popularity and spoke about the production capacity that was aimed at creating such devices. In addition, they are so popular that radio amateurs still use these transistors in some circuits. It’s not surprising, because you can buy them now. Although it is not always necessary to purchase - sometimes it is enough to disassemble equipment originally from the USSR.

Hello everyone! Since I have a penchant for every barrel, I can’t ignore such an important topic!

Excerpt from Wikipedia with my additions:
- a type of silicon bipolar transistor, n-p-n conductivity, which is most widely used in Soviet electronic equipment.
In 1966, A.I. Shokin (at that time the Minister of Electronic Industry of the USSR) read news in the Electronics magazine about the development in the USA of a transistor, technologically adapted for mass production using the assembly method on a continuous tape on magnetic storage drums. The development of the transistor and equipment for production were undertaken by the Pulsar Research Institute, the Fryazino Semiconductor Plant and its Design Bureau. Already in 1967 (!), production preparations were made to launch mass production, and in 1968 (!) the first electronic devices based on KT315 were released.
So KT315 became the first mass-produced low-cost transistor with code marking in a miniature plastic case KT-13. On it, in the upper left corner (and sometimes in the upper right) of the flat side, a letter was placed indicating the group, and the date of manufacture was indicated below (in digital form or alphabetic encryption). There was also a symbol of the manufacturer.
The development of KT315 was awarded in 1973 with the USSR State Prize.
A few years later, in the same KT-13 package, they began to produce a transistor with pnp conductivity - KT361. To differ from KT315, the letter designating the group was placed in the middle of the upper part on the flat side of the case, and it was also enclosed in a “dash”.

Here's from my stock:

Open in new window. Size 1600x1200 (for wallpaper)

Their color variety is also pleasing:

Starting from dark orange and ending with black)))

Moreover, I have a KT315 already produced in 1994.

In the illustration below, I show an image of the transistor itself (in this case, on the left is KT315G, on the right is KT361G) and a conventional graphic display on the circuit diagrams of bipolar transistors of both conductivities.
The pinout is also indicated (they are the same), and the graphical image shows the transistor outputs - TO collector, B aza, E mitter.

Almost every domestically produced board (read: produced in the former USSR) used these cheap, low-power transistors. Having soldered them, radio amateurs of that time successfully used these three-legged friends in their crafts. As practice shows, they were almost always in good working order. But still, sometimes you come across “dead” ones (one junction is broken/shorted - electrical resistance = 0, or is in a break - electrical resistance = infinity). It was also rare to come across a manufacturing defect (a completely new transistor was “dead”), and a marking from the category of “automatic line adjuster in production, Uncle Vanya, before launching the next batch of transistors for stamping, grabbed 100-150 grams to restore strength. ":)

It is simply not clear whether the letter on the transistor is on the left or on the right. There were transistors with markings from the category “the letter is not on the left, nor on the right, nor in the middle.”))))

To combat these troubles, any working device for checking PN junctions comes to our aid. With its help, we can perform a simple test of transistors. As we know, bipolar transistors of the NPN and PNP structure can be conditionally (and only conditionally! No two separate diodes will NEVER replace a bipolar transistor!) represented as single PN junctions. We return to the illustration above and observe in the lower left corner the equivalent of the NPN transistor KT315 displayed exclusively “for testing with a device” in the form of two diodes VD1, VD2.
Since KT361 is a transistor of opposite conductivity - PNP, the polarity of the diodes in its equivalent circuit simply changes (illustration below, right).
Let's move on to practice - let's check our beloved KT315 for serviceability. We take a multimeter that comes to hand.
One of my testers:

Turn it on. A tester with automatic selection of measurement limits, but this will not stop us :)
2 - set the switch to the “continuity” mode, measuring semiconductors, measuring electrical resistance.
3 - use the manual selection button to set the “semiconductor testing” mode
1 - a conditional graphic display of the diode is displayed on the left of the LCD indicator.
From the figure above you can see that for NPN transistors (which our KT315 is), when measuring Base-Emitter and Base-Collector, the measuring device should show the presence of a PN junction (a regular silicon diode in the open state in this case). If the tester probe with a negative potential (for all normal Chinese testers it is black) is connected to the base of the transistor, and the probe with a positive potential (black as standard) is connected to the emitter or collector (which corresponds to the emitter-base and collector-base tests), then a negligible current will flow through the conventional diodes (reverse leakage current, usually microamperes), which the device will not display, i.e. the diodes will be in the closed state - their resistance is equal to infinity. Let's try:

Base-emitter check. The device shows an almost standard voltage drop across a silicon diode = 0.7V; at almost standard current for multimeters.

Base-emitter check. Again, according to the transistor test picture, we see the same voltage drop = 0.7V at the same PN junction.
Conclusion - when connected directly, both transitions are absolutely operational.
If the device showed a voltage drop close to zero or in the “continuity” mode the tester beeped, this would signal a short circuit in one of the junctions being tested. If the device showed an infinite voltage drop or infinite resistance, this would signal an open circuit in the given junction being measured.
The emitter-collector legs should also not “ring” in any direction.

Now let’s check the serviceability of the PNP transistor, in our case KT361.
From the same figure above (right, below) it is clear that transistors of this conductivity have emitter-base and collector-base PN junctions (as I said, exactly the opposite of the structure of an NPN transistor - the polarities of the semiconductors change).
We check:

At the PN junction the emitter-base drop is 0.7V. Further:

The collector-base is also 0.7V. There is no short circuit or break in any of the transitions. Diagnosis - the transistor is working. Let's go solder!

Verse about KT315(lurkmore.ru/KT315)
You were created for HF,
But they even soldered into ULF.
Have you monitored the voltage in the power supply?
And he himself ate from the IP.
You worked in GHF and GLF,
They even put you in the HRC.
You are a good generator
Amplifier, switch.
You're worth a penny
But microcircuits have come to replace you.

In order to solve, under existing conditions, the problems of creating an electronics industry practically from scratch and without the participation of global cooperation, it was necessary to think through a clear program with an integrated approach, based on a combination of a deep understanding of the scientific and technical problems of electronics with an equally deep knowledge of the laws of industrial production. And such a program for transforming the electronics industry of the USSR into one of the most powerful sectors of the national economy was conceived, suffered and developed by the minister and his associates. As a result of its implementation, the Soviet Union for the period from 1960 to 1990. reached third place in the world in the production of electronic components (and for certain types, second and even first). The only country in the world that had the ability to fully provide all modern types of weapons with its own elemental base was the Soviet Union.
By the beginning of the 90s, the total production volume of KT315 transistors at four factories in the industry amounted to about 7 billion units, hundreds of millions were exported, a license for the production technology and a set of equipment were sold abroad.

So the fairy tale ends, thank you for your attention,
Your:)

Love CT scans, and remember the saying: “without a CT scan there is neither here nor there.”))))

There are several reasons for this prevalence. Firstly, its quality. Thanks to the conveyor belt method, which was revolutionary in the late sixties, production costs were reduced to a minimum with very good technical indicators. Hence the second advantage - an affordable price, which allows the use of KT315 transistors in mass consumer and industrial electronics, as well as for amateur radio devices.

The plastic case did not imply high power, but was cheap.

The KT315 transistor was produced in two versions, flat (orange or yellow) and cylindrical (black).

The black transistor had a flat cut; if you position the transistor towards you, the emitter would be on the right, the collector on the left, and the base in the middle.

The KT315 transistor is one of the most popular domestic transistors; it was put into production in 1967. Initially produced in a plastic case KT-13.

KT315 pinout

If you place the KT315 with the markings facing you with the pins facing down, then the left pin is the emitter, the central pin is the collector, and the right pin is the base.

Subsequently, KT315 began to be produced in the KT-26 package (a foreign analogue of TO92), transistors in this package received an additional “1” in the designation, for example KT315G1. The pinout of KT315 in this case is the same as in KT-13.

KT315 parameters

KT315 is a low-power silicon high-frequency bipolar transistor with an n-p-n structure. It has a complementary analogue of KT361 with a p-n-p structure.
Both of these transistors were intended to work in amplifier circuits, both audio and intermediate and high frequencies.
But due to the fact that the characteristics of this transistor were breakthrough, and the cost was lower than existing germanium analogues, KT315 found the widest application in domestic electronic equipment.

The cutoff frequency of the current transfer coefficient in a circuit with a common emitter ( f gr.) – 250 MHz.

The maximum permissible continuous power dissipation of the collector without a heat sink ( P to max)

For KT315A, B, V, D, D, E – 0.15 W;
For KT315Zh, I, N, R – 0.1 W.

The maximum permissible direct collector current ( I to max)

For KT315A, B, V, D, D, E, N, R – 100 mA;
For KT315Zh, I – 50 mA.

Constant base-emitter voltage - 6 V.

The main electrical parameters of KT315, which depend on the letter, are shown in the table.

U kbo- Maximum permissible collector-base voltage,
U keo- Maximum permissible collector-emitter voltage,
h 21e- Static current transfer coefficient of a bipolar transistor in a circuit with a common emitter,
I kbo- Reverse collector current.

Name	U kbo and U keo, V	h 21e	I kbo, µA
KT315A	25	30-120	≤0,5
KT315B	20	50-350	≤0,5
KT315V	40	30-120	≤0,5
KT315G	35	50-350	≤0,5
KT315G1	35	100-350	≤0,5
KT315D	40	20-90	≤0,6
KT315E	35	50-350	≤0,6
KT315ZH	20	30-250	≤0,01
KT315I	60	≥30	≤0,1
KT315N	20	50-350	≤0,6
KT315R	35	150-350	≤0,5

Marking of transistors KT315 and KT361

It was with KT315 that the coded designation of domestic transistors began. I came across KT315 with full markings, but much more often with the only letter from the name shifted slightly to the left of the center; to the right of the letter was the logo of the plant that produced the transistor. KT361 transistors were also marked with one letter, but the letter was located in the center and there were dashes to the left and right of it.

And of course, KT315 has foreign analogues, for example: 2N2476, BSX66, TP3961, 40218.

KT315 pinout, KT315 parameters, KT315 characteristics: 20 comments

Greg
Yes indeed, the legendary red-haired couple! An attempt bequeathed by a legendary personality - and we will go the other way. It didn't work out, which is a pity. Well, it was necessary to think of this, to draw such inconvenient conclusions, allowing bending in only one direction: this is probably not an engineering, but a political decision) But despite this, or maybe because of this, plus a bright festive color... the brightest, entourage, stylish, brutal and unforgettable! I would give him both an Oscar and a Nobel at once.
After changing my outfit - an ordinary, mediocre detail, among thousands of similar ones (
PS The building has changed because the production equipment, over time, was replaced with imported ones, and their machines were not designed for such candy.
1. admin Post author
  The problem was not that the leads were molded only in one plane (for example, in TO-247 cases the leads are also flat), but that they were wide (width 0.95 mm, thickness 0.2 mm) and located close (gap 1 .55 mm). It was very inconvenient to route the board - you couldn’t miss the path between the pins, and you had to drill for KT-13 with a 1.2 mm drill. For other components, 1 mm or even 0.8 mm was enough.
  KT315 was the first domestic transistor manufactured using epitaxial-planar technology, then, after a couple of decades, it already became mediocre among its younger counterparts. And of course, in the 80s, instead of KT315 / KT361, it was more convenient to install KT208 / KT209, KT502 / KT503 or KT3102 / KT3107, depending on what tasks the transistor faced.
  And I doubt that the KT-13 body was a domestic invention, it seems that there were Japanese parts in such cases, so most likely they unsuccessfully adopted someone else’s experience...
Greg
The East is a delicate matter... In the middle of the last century there was a stubborn struggle between the superpowers for the redistribution of spheres of influence. For some, Japan - bombs, and for others - technology. And the cunning Japanese accepted any help and grabbed everything they gave... Then, naturally, they chose the best, and therefore technologically advanced. They, uncreative people, won - Techno-Logicity) The USSR not only built the first radio plant for them, but also the first automobile plant, for example. Subsequently, manufactured cars began to differ from ours no less than radio components. The issue of priority here is controversial, due to international friendship and the compatibility of the then developments.
1. Vova
  The USSR sold licenses abroad for the production of KT315, apparently the Japanese also bought one. And they sent an entire KT315 production line from Voronezh to Poland. Apparently under the program to support countries in the socialist camp.
Chupacabra
In terms of popularity, the KT315 can only be compared with the MP42B.

I didn’t come across KT315 with strange letters, it turns out they were specialized transistors:
- KT315I were intended for switching circuits of segments of vacuum fluorescent indicators;
- KT315N were intended for use in color television;
- KT315R were intended for Elektronika-VM video recorders.
Alexandre
Yes, not convenient conclusions, but there were no other transistors then. Lately, about 20 years ago, these transistors have been readily available and can be obtained for free. It won't burn, it's good for beginners. It is good to solder on breadboards.
Root
Yes, they have normal bodies. Flat, you can put dozens of them in one row at a minimum distance from each other, just like you can’t put transistors in TO-92. This is relevant when there are a lot of them on the board, for example, keys for multi-segment VLIs. Tape terminals (a tribute to the manufacturability of transistors) also do not create any particular inconvenience; I do not see any urgent need to bend the terminals in different directions. We don’t bend the pins of the microcircuits and this doesn’t interfere with the tracing at all.

I never thought about the width of the KT315 pins. I always drilled everything mainly with a 0.8 mm drill and 315_e (of which I have a half-liter jar, bought on occasion at the market) always fell into place normally, without any violence on my part :) Now I specially measured it with a caliper, the width of the leads is 0.8 millimeters .
1. Root
  Out of curiosity. I read on some website about the manufacture of the output stage of a powerful ultrasonic sounder using dozens of parallelized KT315 and KT361. The transistors are in one line with their side surfaces facing each other, and are clamped between aluminum plates with thermal paste. I don’t remember the characteristics of the amplifier, and the author of this design did not expect high sound quality when making the UMZCH on the 315_x as a technical curiosity.

Victor

“Sweet couple” - 315,361. There is so much soldered onto them. It’s as if they were made specifically for breadboards with their flat terminals. I still feel warm when I take them in my hands. I grew up in times of shortage. They are in a box. They are waiting for their grandson to grow up.

mobilander

A lot of the old circuitry used transistors of the 315 and 361 series. By the way, I soldered a lot of things on them myself, but the location of the pins itself is very inconvenient. I would change the collector and emitter or base. then the layout of the boards would be much more compact.

Greg
Well, that’s why he’s red, so that everything is different from the majority) There are some difficulties with the technology of this arrangement of pins, E_B_K is easier to make than E_K_B, but for some reason they went for it. And the tape contact is unreasonably wide, which resulted in an unjustified increase in the body... First pancake? Our response to Chamberlain? Failed development forecasting? False premises? History is silent, but I would like to look at the patent and copyright documents, but this is also a mystery.

As far as I remember in tape recorders, KT315-KT361 was replaced by KT208-KT209, KT502-KT503, then KT3102-KT3107. If you have any of these transistors, you can try to select them according to the parameters, of course the result is not guaranteed, and their housings are different.
If it’s not for sporting reasons that everything should be as the speaker designer intended, especially since all the transistors in the amplifier have burned out, then I would insert some modern board with operational amplifiers into the column.

Mitya

What can I replace these transes with? For which transfers exactly?

Kemran

Hello everyone, I have a problem with these transoms, you can’t buy them from us, I don’t have them in stock either, but I used them up, my question is what kind of transoms can I exchange 315Bi 361b for?

Greg
The admin has already written above, but I will repeat in more detail. The most appropriate, in most respects, replacement for the KT315/KT361 pair is KT502/KT503. Suitable for most schematic solutions, even without recalculating the master and correction circuits. If the schematic emphasis is on key, discrete signal processing, you can use KT3102/KT3107, which is often even better. KT208/KT209 are also quite suitable. But, if used in analog amplification circuits, then it is better to correct the driving circuits.

Vladimir

In sound amplifiers you can use MP41A and MP37A in a pair instead of KT361 and, accordingly, KT315. Why with the letter A, the voltage for MP37A is 30 Volts, for other letters it is below 20 Volts. MP41 can be replaced with MP42, MP25, MP26; the latter two have a minimum voltage of 25 and 40 Volts, so you need to look at the voltage of the power source. Typically 12 or 25 volts in older model amps.

On a day off, I decided to build a video amplifier for my Dendy game console to improve the video image quality. The circuit is quite simple and has no more than a dozen radio components. It is assembled on very common Soviet transistors, visually very similar, read a useful article, how to distinguish transistor KT315 from KT361?

A little about transistors KT315 and KT361

One of the most common high-frequency transistors, made of silicon, the reserves of which on our planet are very impressive. KT 315 has n-p-n conductivity, KT 361 has the opposite. They are united by the type of housing, KT 13, and very often, these bipolar transistors are used in pairs. They have become widespread in domestic electronics, in amplification and conversion circuits.

How to distinguish KT315 from KT361

As a rule, these transistors are produced in a plastic case, in several color options, yellow, red, brown. To compare them, we place their markings towards us. We look at the marking, or rather at its location, on the transistor body.

To identify the KT315 transistor, a letter will be printed on its body, it will be placed on the top left side of it. For kt361, the letter will be located strictly in the center.
They will have the same pinout, in this sequence, emitter, collector, base.

Table 1 - Brief technical characteristics of transistors KT315 and KT315-1

Table 2 - Marking of the KT315-1 transistor with a code sign

Table 3 - Foreign analogues of the KT315 transistor

Table 4 – Electrical parameters of KT315 transistors upon acceptance and delivery

Table 5 – Maximum permissible operating modes of the KT315 transistor

About production

This is the collection I found:

What's inside?

Comparison

Future

Table 1 - Brief technical characteristics of transistors KT315 and KT315-1

Table 2 - Marking of the KT315-1 transistor with a code sign

Table 3 - Foreign analogues of the KT315 transistor

Table 4 – Electrical parameters of KT315 transistors upon acceptance and delivery

Table 5 – Maximum permissible operating modes of the KT315 transistor

Transistor KT315

Development

Technology

Applications and complementary technologies

Conclusion

KT315 pinout

KT315 parameters

Marking of transistors KT315 and KT361

A little about transistors KT315 and KT361

How to distinguish KT315 from KT361

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