JIS semiconductor designation
# JIS semiconductor designation

Japanese Industrial Standards (JIS) has standard JIS-C-7012 for semiconductor part numbers. The first digit denotes the p-n junction count ("3" may also denote a dual-gate FET); then follows the letter "S", then:

| 2nd letter | Type of semiconductor |
| - | - |
| <none> | Diode |
| A | high frequency PNP BJTs |
| B | audio frequency PNP BJTs |
| C | high frequency NPN BJTs |
| D | audio frequency NPN BJTs |
| E | Diode |
| F | Thyristor |
| G | Gunn diode |
| H | UJT |
| J | P-channel FETs (both JFETs and MOSFETs) |
| K | N-channel FETs (both JFETs and MOSFETs) |
| M | TRIAC |
| Q | LED |
| R | Rectifier |
| S | Signal diode |
| T | Avalanche diode |
| V | Varicap |
| Z | Zener Diode |

Then follows the Japan Electronics and Information Technology Industries Association's Electronic DEvice REgistration Center (JEITA-EDEREC)-assigned part number, optionally followed by suffixes (such as "A", "B", "C", or "R", "O", "BL", standing for "Red", "Orange", "Blue" etc.) to denote variants, such as tighter $h_{FE}$ (gain) groupings.

Example: 2SD965, but sometimes the "2S" prefix is not marked on the package – a 2SD965 might only be marked "D965"; a 2SC1815 might be listed by a supplier as simply "C1815", thus possibly creating confusion with Pro Electron abbreviated markings, because a transistor marked "D965" might either be a 2SD965 or a BD965.

