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. They were created by Philips and Mullard 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 (hFE and hfe) groupings, as well as complementary PNP types. Some manufacturers have specified their parts with a higher power dissipation rating (Ptot) than others.
Contents
The BC548 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 version.
Table of BC107 to BC860 Variants
(see also: [1] for a neat summary of some of the family).
Noise Figure (at 1kHz, for 2 kilohm source, BW=200Hz, IC=0.2mA/VCE=5V) is <10dB for those not tabulated as "Low Noise".
Current Ratings
All types have a maximum collector current of 100mA, except that the original Philips tentative data dated 4.4.1966 specified a maximum collector current of 100mA peak (ICM) for the BC107/8/9, and Telefunken originally specified a maximum collector current of 50mA for the BC109, but since at least 1973 all have revised collector currents of 100mA average or 200mA peak, except that the BC317-BC322 range have a 150mA (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 (hFE) groups (see BC548 Gain groupings).