2N3055
The 2N3055 is a bipolar silicon - NPN power transistor in a TO3 package and one of the most popular power transistors .
It was brought onto the market by RCA in the early 1960s and later produced by many American, Japanese and European manufacturers, some of which had not inconsiderably different data.
Through the development of modern power transistors with better overall properties - such as types of thin-film wafers manufactured bipolar epitaxial - and bipolar IGBT - and unipolar vmos-FET power transistors - the 2N3055 has now become less important; but it is still produced and v. a. Used as a spare part, in non-frequency critical applications or by hobbyists.
Electrical characteristics
The 2N3055 can block a voltage of up to 60 V in the emitter-collector path , the maximum current through the collector is 15 A and the permissible power loss at a housing temperature of T C = 25 ° C is 115 W (data according to data sheet from ON Semiconductor ). An advantage of previous manufacturing processes for the 2N3055 was the area of the second breakdown (English secondary breakdown ) with typically high values for collector current and collector-emitter voltage.
The deviations from previous specifications of the 2N3055 associated with modern epitaxial technology concern v. a. the increase in the transit frequency from the original 800 kHz to 2.5 MHz, a reduced feedback capacity, higher values for large and small signal amplification and the narrowing of the safe working area . Their replacement for older types in existing circuits is therefore not always possible without problems.
Development history
At the beginning of the 1960s, RCA was one of the first manufacturers to bring the 2N3055 onto the market under the US JEDEC standard introduced in 1958 . At that time, the semiconductor industry had little experience in silicon technology. The manufacturing process at that time used a p-doped wafer for the base electrode, on which the collector and emitter were manufactured on both sides - RCA called this structure the “hometaxial base”. The 2N3055 quickly replaced in many devices, such as B. in amplifiers and regulated power supplies , the electron tubes and germanium transistors widespread at the time . Since the original manufacturing process had already become inefficient in the 1970s, the more advanced epitaxial process was used, which also enabled the manufacture of the complementary (PNP) MJ2955. Transistors similar to the 2N3055 based on this process were the BD130 Y , mainly manufactured by Siemens in the 1970s under the European Pro-Electron name, and the KD503 by Tesla , which was produced in the ČSSR for use in the former Eastern Bloc .
Current availability
With the falling demand, the 2N3055 is only produced by a few manufacturers, due to the practically barely cost-covering production (market prices around 1 $ and less) exclusively in highly doped versions with reduced chip areas to limit the consumption of the expensive ultra-pure silicon . The drop in prices means that batches with significantly too low power dissipation appear again and again in the trade, which are fraudulently not specified truthfully with radically reduced use of silicon.
Individual evidence
- ↑ Power-Complementary - profusionplc.com, examples of modern bipolar power transistors from Sanken Electric
- ↑ a b Data Sheet 2N3055 (NPN), MJ2955 (PNP) - On Semiconductor, PDF, December 2005; See data sheet 2N3055 - Central Semiconductor, PDF, July 2013
- ^ John N. Ellis, Vince S. Osadchy: The 2N3055: A Case History . In: IEEE Trans. Electron Devices . 84, No. 11, 2001, pp. 2477-2483.
