BC548
Encyclopedia
The BC548 is a general purpose silicon NPN BJT
transistor
found commonly in European electronic equipment; the part number is assigned by Pro Electron
, which allows many manufacturers to offer electrically and physically interchangeable parts under one identification. The BC548 is commonly available in European Union and Commonwealth Countries and is often the first type of bipolar transistor young hobbyists encounter. The BC548 is often featured in circuit diagrams and designs published in Electronics Magazines such as "Silicon Chip" and "Elektor".
As a representative of the large family of bipolar transistors the BC548 provides a "stepping off point" to the use of more esoteric, higher voltage, current or frequency devices for beginners.
If the TO-92 package is held in front of one's face with the flat side facing toward you and the leads downward, (see picture) the order of the leads, from left to right is collector, base, emitter.
and Telefunken
are two manufacturers of the BC548.
numbered NPN 2N3904
and PNP 2N3906
possess very similar electrical characteristics to the BC548 and BC558 respectively but the pin outs are reversed. If the TO-92 package for these devices is held in front of one's face with the flat side facing toward you and the leads downward, (see picture) the order of the leads, from left to right is emitter, base, collector.
The Electronic Industries Association of Japan
(EIAJ) assigns the 2SC prefix to NPN transistors for high frequency use. The NPN 2SC1815 and PNP 2SA1015 are usually the most the common general purpose devices which are encountered and also possess characteristics which are similar to the BC548 and BC558. If the TO-92 package for these devices is held in front of one's face with the flat side facing toward you and the leads downward, (see picture) the order of the leads, from left to right is emitter, collector, base.
In more demanding applications, such as power conversion or high frequency equipment, devices must be more carefully chosen depending upon the task and position in the circuit.
These are similar to the North American 2N2219 and 2N2906.
The BC639 and BC640 are similar to the above two devices but possess a greater Vcebo of 100v. The pin outs of these devices differ from most of the other "BC" family with the collector lead in the middle for heat dissipation.
These devices are similar to the North American 2N2222
ans 2N2907
.
There are many other devices based on the BC54x family, such as the surface-mount versions of the BC547, 548 and 549; the BC847, BC848 and BC849 which are almost electrically identical but housed in tiny surface mount
TO-236 packages. These tiny packages are marked with a two or three symbol code which must be translated back into the actual number using a conversion table because the actual number is too large to fit on the tiny package top.
Bipolar junction transistor
|- align = "center"| || PNP|- align = "center"| || NPNA bipolar transistor is a three-terminal electronic device constructed of doped semiconductor material and may be used in amplifying or switching applications. Bipolar transistors are so named because their operation involves both electrons...
transistor
Transistor
A transistor is a semiconductor device used to amplify and switch electronic signals and power. It is composed of a semiconductor material with at least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistor's terminals changes the current...
found commonly in European electronic equipment; the part number is assigned by Pro Electron
Pro Electron
Pro Electron is the European type designation and registration system for active components .Pro Electron was set up in 1966 in Brussels, Belgium...
, which allows many manufacturers to offer electrically and physically interchangeable parts under one identification. The BC548 is commonly available in European Union and Commonwealth Countries and is often the first type of bipolar transistor young hobbyists encounter. The BC548 is often featured in circuit diagrams and designs published in Electronics Magazines such as "Silicon Chip" and "Elektor".
As a representative of the large family of bipolar transistors the BC548 provides a "stepping off point" to the use of more esoteric, higher voltage, current or frequency devices for beginners.
If the TO-92 package is held in front of one's face with the flat side facing toward you and the leads downward, (see picture) the order of the leads, from left to right is collector, base, emitter.
Specifications
The exact specs of a given device depend on the manufacturer. It is important to check the datasheet for the exact device and brand you are dealing with. PhilipsPhilips
Koninklijke Philips Electronics N.V. , more commonly known as Philips, is a multinational Dutch electronics company....
and Telefunken
Telefunken
Telefunken is a German radio and television apparatus company, founded in Berlin in 1903, as a joint venture of Siemens & Halske and the Allgemeine Elektricitäts-Gesellschaft...
are two manufacturers of the BC548.
- Vcbo = 30 VVoltThe volt is the SI derived unit for electric potential, electric potential difference, and electromotive force. The volt is named in honor of the Italian physicist Alessandro Volta , who invented the voltaic pile, possibly the first chemical battery.- Definition :A single volt is defined as the...
- Ic = 100 mA
- Ptotal = 50 mW
- ft = 300 MHz
JEDEC and JIA standards
The JEDECJEDEC
The JEDEC Solid State Technology Association, formerly known as the Joint Electron Devices Engineering Council , is an independent semiconductor engineering trade organization and standardization body...
numbered NPN 2N3904
2N3904
The 2N3904 is a common NPN bipolar junction transistor used for general purpose low-power amplifying or switching applications. The type was registered by Motorola Semiconductor in the mid-sixties, together with the complementary PNP type 2N3906, and represented a significant performance/cost...
and PNP 2N3906
2N3906
The 2N3906 is a common PNP bipolar junction transistor used for general purpose low-power amplifying or switching applications. Compared to the general run of silicon transistors, it is designed for low current and power and medium voltage, and can operate at moderately high speeds...
possess very similar electrical characteristics to the BC548 and BC558 respectively but the pin outs are reversed. If the TO-92 package for these devices is held in front of one's face with the flat side facing toward you and the leads downward, (see picture) the order of the leads, from left to right is emitter, base, collector.
The Electronic Industries Association of Japan
Electronic Industries Association of Japan
Founded in 1948, the Electronic Industries Association of Japan was one of two Japanese electronics trade organizations that were merged into the Japan Electronics and Information Technology Industries Association ....
(EIAJ) assigns the 2SC prefix to NPN transistors for high frequency use. The NPN 2SC1815 and PNP 2SA1015 are usually the most the common general purpose devices which are encountered and also possess characteristics which are similar to the BC548 and BC558. If the TO-92 package for these devices is held in front of one's face with the flat side facing toward you and the leads downward, (see picture) the order of the leads, from left to right is emitter, collector, base.
Use in hobbyist circuits
Generally all of the above devices can be used interchangeably in low powered hobby electronic circuits operating at frequencies op to 200MHz or so. "Elektor" magazine has coined the term "DUS TUP TUN", meaning "Diode Universal, Silicon", "Transistor universal P.N.P." and "Transistor Universal N.P.N.", where the "DUS" means something like a 1N4148 or 1N914, two very commonly encountered small signal silicon diodes, the "TUP" referring to the BC558, 2N3906 or 2SA1015 and the "TUN" referring to the BC548, 2N3904 or 2SC1815. This allowed their magazine to be sold in different geographical realms and circuit constructors need only be aware of the pin-out configurations of the devices available in their particular realm.In more demanding applications, such as power conversion or high frequency equipment, devices must be more carefully chosen depending upon the task and position in the circuit.
Related transistors
The BC140 and BC160 are complimentary devices which are similar to the BC548 and BC558 but possess a collector currents of 1A and a Vcebo of 80v.These are similar to the North American 2N2219 and 2N2906.
The BC639 and BC640 are similar to the above two devices but possess a greater Vcebo of 100v. The pin outs of these devices differ from most of the other "BC" family with the collector lead in the middle for heat dissipation.
These devices are similar to the North American 2N2222
2N2222
The 2N2222 is a common NPN bipolar junction transistor used for general purpose low-power amplifying or switching applications. It is designed for low to medium current, low power, medium voltage, and can operate at moderately high speeds. It is made in the TO-18 metal can as shown in the picture...
ans 2N2907
2N2907
The 2N2907 is a PNP bipolar junction transistor used for general purpose low-power amplifying or switching applications. It is designed for low to medium current, low power, medium voltage, and can operate at moderately high speeds. This part number was made by several manufacturers; Texas...
.
There are many other devices based on the BC54x family, such as the surface-mount versions of the BC547, 548 and 549; the BC847, BC848 and BC849 which are almost electrically identical but housed in tiny surface mount
Surface-mount technology
Surface mount technology is a method for constructing electronic circuits in which the components are mounted directly onto the surface of printed circuit boards . An electronic device so made is called a surface mount device...
TO-236 packages. These tiny packages are marked with a two or three symbol code which must be translated back into the actual number using a conversion table because the actual number is too large to fit on the tiny package top.