Each Semiconductor devices have a special numbering coding as per specification of that components. All Components have a particular symbolic numbering with Alphanumeric coding for represents their characteristics of material and other parameters. There are international numbering system for all semiconductor devices and components .
A – Germanium
B – Silicon
C – Gallium Arsenide
D – Photodiodes
A – General Purpose diode
B – Variable capacitance (Varactor) diode
C – Audio Frequency (AF) Low Power Transistor
D – AF Power Transistor
E – Tunnel diode
F – High frequency(HF) Low power transistor
G – Multiple Devices
H – Magnetic Sensitive devices
K – Hall effect Modulator
P – Photo diode/Radiation sensitive diode
Q – Light Emitting Diode/Radiation generating diode
R – Thyristor (SCR or Triac)
S – Low Power Switching transistor
T – High Power transistor
U – Power Switching transistor
X – Diode , Multiplier
Y – Power rectifier
Z – Zener Diode
Third letter –
The third letter does not have any particular significance. The letter is used to mention the specialized application of the diode.
The second letter is 'N', and then first digit is 1 for diodes, 2 for transistors, 3 for four-leaded devices, and so forth. But 4N and 5N are only used for opto-couplers. The sequential numbers run from 100 to 9999 and indicate the approximate time the device was first made. 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: 1N4007, 1N914 (diode) and 2N2222, 2N3904 (transistors).
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 (High Frequency) Transistor
SB – PNP AF(Audio frequency) Transistor
SC – NPN HF(High Frequency ) Transistor
SD – NPN AF Transistor
SE - Diodes
SF – Thyristors
SG – P-channel FET
SH – UJT
SK – N- channel FET
SM - Triac
SQ – LED
SR – Rectifier
SS – Signal diode
ST – Avalanche diode
SV - Varicap
SZ – Zener diode
If any suffix presents then for this suffix Always check the data sheet because it represents various things. For example, a 2N2222A is an enhanced version of a 2N2222. It has higher gain, frequency, and voltage ratings.
an additional letter for Zener Diodes will appear after the numbers. This letter denotes the tolerance of the zener voltages. The following letters are used for denoting of tolerance of Zener Diodes.
Zener diodes have additional characters which will indicate the zener voltage.
Ex: 5V1 indicate 5.1V
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)
Examples: ZTX302, TIP31A, MJE3055.