The BC107, BC108 and BC109 are general-purpose low power silicon NPN bipolar junction transistors found very often in equipment and electronics books/articles from Europe, Australia and many other countries from the

1960s File:1960s montage.png, Clockwise from top left: U.S. soldiers during the Vietnam War; the Beatles led the British Invasion of the U.S. music market; a half-a-million people participate in the 1969 Woodstock Festival; Neil Armstrong and Buzz ...

. They were created by

Philips Koninklijke Philips N.V. (), commonly shortened to Philips, is a Dutch multinational conglomerate corporation that was founded in Eindhoven in 1891. Since 1997, it has been mostly headquartered in Amsterdam, though the Benelux headquarters i ...

and

Mullard Mullard Limited was a British manufacturer of electronic components. The Mullard Radio Valve Co. Ltd. of Southfields, London, was founded in 1920 by Captain Stanley R. Mullard, who had previously designed thermionic valves for the Admiral ...

in 1963 and introduced in April 1966. Initially in metal (TO-18) packages, the range expanded over time to include other package types, higher voltage ratings, and a better selection of gain (h_FE and h_fe) groupings, as well as complementary PNP types. Some manufacturers have specified their parts with a higher power dissipation rating (P_tot) than others. The

BC548 The BC548 is a general-purpose NPN bipolar junction transistor commonly used in European and American electronic equipment. It is notably often the first type of bipolar transistor hobbyists encounter and is often featured in designs in hobby elec ...

is an example of the modern low-cost member of this family, still in a through-hole package, while the BC848 is the

surface-mount Surface-mount technology (SMT), originally called planar mounting, is a method in which the electrical components are mounted directly onto the surface of a printed circuit board (PCB). An electrical component mounted in this manner is referred ...

version.

Table of BC107 to BC860 variants

(See also

for a neat summary of some of the family). Noise figure (at 1 kHz, for a 2 kilohm source, BW = 200 Hz, I_C=0.2 mA/V_CE=5 V) is <10 dB for those not tabulated as "Low Noise".

Current ratings

All types have a maximum collector current of 100 mA, except that the original Philips tentative data dated 4.4.1966 specified a maximum collector current of 100 mA ''peak'' (I_CM) for the BC107/8/9, and Telefunken originally specified a maximum collector current of 50 mA for the BC109, but since at least 1973 all have revised collector currents of 100 mA average or 200 mA peak, except that the BC317-BC322 range have a 150 mA (continuous) rating.

A,B and C gain groupings

The above devices' type numbers may be followed by a letter "A" to "C" to indicate low to high gain ( Bipolar junction transistor#h-parameter_model, h_FE) groups (see BC548 Gain groupings).

Other characteristics

Transistors in this family: * require a base-emitter voltage (V_BE(on)) in the range of 0.55 to 0.7 volts for a collector current of 2 mA when the Collector voltage is 5 volts. * Will have a saturation voltage (V_CE(sat)) of at most 0.2 volts (typically 0.07 volts) at a collector current of 10 mA and a base current of 0.5 mA (when the base voltage is typically 0.73 volts; 0.83 volts maximum). * Has greater than unity current gain up to a frequency (f_T) of at least 150 MHz, typically 250 MHz, at a collector current of 10 mA (typically 85 MHz and a collector current of 0.5 mA)

References

{{Reflist

Table of BC107 to BC860 variants

Current ratings

A,B and C gain groupings

Other characteristics

See also

References

Further reading