Skip to main content

Transistor numbers and codes

Most transistor markings follow one of these codes: JEDEC, JIS or Pro-Electron. For ICs, look for known
numbers (e.g. 741, 4001, 7400) between the prefix and the suffix. Don't confuse it with the date code. ICs typically have two numbers: The part number and the date code. 1. Joint Electron Device Engineering Council (JEDEC)
These part numbers take the form: digit, letter, sequential number, [suffix]
The letter is always 'N', and the first digit is 1 for diodes, 2 for transistors, 3 for four-leaded devices, and so forth. But 4N and 5N are reserved for opto-couplers. The sequential numbers run from 100 to 9999 and indicate the approximate time the device was first made.
If present, a suffix could indicate various things. For example, a 2N2222A is an enhanced version of a 2N2222. It has higher gain, frequency, and voltage ratings. Always check the data sheet.

Examples: 1N914 (diode), 2N2222, 2N2222A, 2N904 (transistors).

NOTE: When a metal-can version of a JEDEC transistor is remade in a plastic package, it is often given a number such as PN2222A which is a 2N2222A in a plastic case.

2. Japanese Industrial Standard (JIS)
These part numbers take the form: digit, two letters, sequential number, [optional suffix]

Digits are 1 for diodes, 2 for transistors, and so forth. The letters indicate the type and intended application of the device according to the following code:

SA: PNP HF transistor
SC: NPN HF transistor
SE: Diodes
SG: Gunn devices
SJ: P-channel FET
SM: Triac
SR: Rectifier
ST: Avalanche diodes
SZ: Zener diodes
SB: PNP AF transistor
SD: NPN AF transistor
SF: Thyristors
SH: UJT
SK: N-channel FET
SQ: LED
SS: Signal diodes
SV: Varicaps

The sequential numbers run from 10-9999. The optional suffix indicates that the type is approved for use by various Japanese organizations. Since the code for transistors always begins with 2S, it is sometimes omitted; for example, a 2SC733 could be marked C733.

Examples: 2SA1187, 2SB646, 2SC733.

3. Pro-Electron (European)
These part numbers take the form: two letters, [letter], sequential number, [suffix]

The first letter indicates the material:
A = Ge
B = Si
C = GaAs
R = compound materials.

The second letter indicates the device type and intended application:
A: diode, RF
B: diode,varactor
C: transistor, AF, small signal
D: transistor, AF, power
E: Tunnel diode
F: transistor, HF, small signal
K: Hall effect device
L: Transistor, HF, power
N: Opto-coupler
P: Radiation sensitive device
Q: Radiation producing device
R: Thyristor, Low power
T: Thyristor, Power
U: Transistor, power, switching
Y: Rectifier
Z: Zener, or voltage regulator diode

The third letter indicates if the device is intended for industrial or commercial applications. It's usually a W, X, Y, or Z. The sequential numbers run from 100-9999.

Examples: BC108A, BAW68, BF239, BFY51.

Instead of 2N and so forth, some manufacturers use their own system of designations. Some common prefixes are:

MJ: Motorola power, metal case
MJE: Motorola power, plastic case
MPS: Motorola low power, plastic case
MRF: Motorola HF, VHF and microwave transistor
RCA: RCA device
TIP: Texas Instruments (TI) power transistor, plastic case
TIPL: TI planar power transistor
TIS: TI small signal transistor (plastic case)
ZT: Ferranti
ZTX: Ferranti

Examples: ZTX302, TIP31A, MJE3055.

Many manufacturers also make custom parts, or custom-label standard parts, for large volume OEM customers. Typically, they have the OEM's mark or logo and part-number. When such parts hit the surplus market, they end up in hobbyist "bargain packs". Since data on these devices is not usually available, they are best used as LED-drivers and other such applications where the actual specifications are not critical.

Comments

Popular posts from this blog

How to read value of a Capacitor ?

Capacitance is the ability to store electrons and is measured in Farads.One Farad is a very large value! So most capacitors used in electronic circuits  are measured in MicroFarads (uF) or even Picofarads (pF). Capacitance = Q / V Where Q is the charge and V is the voltage. Thus the capacitance is the charge divided by voltage. The important parameters of the capacitor are 1. Value -Value is marked on the capacitor directly or in colour codes 2. Tolerance -It indicates how much more or less the actual capacitance of the capacitor 3. Working voltage -It is the maximum voltage a capacitor can withstand before the dielectric breakdown 4. Leakage current .There is always small leakage current in all capacitors. Ideally this should be zero. But no capacitor is perfect without leakage current. Tantalum capacitor is comparatively better with minimum leakage current  Value 1pf (Pico Farad)    = 0.001nf (Nano Farad) 1nf (Nano Farad)   = 0.001μf (Micro Farad) 1μf (Micro farad) =

Ring tester

 In my Electronic repair job I found normal multimeter is somewhat limited  in certain area. so special tools are needed for saving  a lot of time  Ring tester is one of this kind .helping me to check small hi Q inductors SMPS transformer, TV Deflection coils ,LOT ,line driver transformer and almost any inductor working on hi frequency.Normal multimeter can only identify a open coil ,but not a shorted windings.  I found some commercial available ring tester. but it is not available in local shops of my area.also it seems priced high. So  I decided to make a ring tester of my own. Below is the one I successfully made from the junk box components. I found it very useful. and now it is one of my best test tool collection. Two Ic's, few LED's ,one plastic container and few resistors  made this wonderful tool. If we test it with primary of SMPS transformer or LOT windings of a good one shows all its LEDs will light. depending on the inductive reactantce  the number of LED 's