Transistors fall into two basic designs--the PNP transistor or the NPN transistor--yet there are thousands of types. Each is made to affect a circuit in a certain capacity under a given load. Replacement transistors must match the specific design, construction materials and load capacity of the originals. Codes have been established for semiconductors by three organizations and several manufacturers. Printed codes on the body of the components identify each with letters and numbers that can be used to find matching replacements.
Instructions
1. Identify Joint Electron Devices Engineering Council codes. JEDEC uses codes comprised of a digit, letter, serial number and sometimes a suffix letter. The initial number represents the number of connections on the component minus 1. The number 2 is most common for transistors. The letter following is N for all JEDEC codes. The serial number falls between 100 and 9999. Optional suffixes A, B and C indicate low, medium and high gain respectively.
2. Identify Japanese Industrial Standard codes. JIS codes contain a digit followed by two letters and a serial number. The first number show how many connections the component has minus 1, with 2 being the most common. The two letters indicate the component type, with S being the first letter. Serial numbers run from 10 to 9999.
3. Identify Pro-Electron codes of European manufacturers. Pro-Electron features two letters and an optional third letter followed by a serial number and an optional suffix. The first letter will be A, B,C or R to indicate the construction material. The second letter shows the component application. A third letter, usually between W and Z, indicates noncommercial use. Serial numbers are from 100 to 9999 and the suffix letter shows the gain with A, B and C for low, medium and high gains just as the JEDEC codes.
4. Identify manufacturer codes. Several manufacturers including Motorola, RCA and Texas Instruments stamp codes on their components that do not comply with any of the three electronic manufacturers committee standards. Generally manufacturer codes begin with letters that do not match JEDEC, JIS or Pro-Electron code letters.
Tags: serial number, component minus, connections component, connections component minus, first letter, from 9999, JEDEC codes