The BC548 family, including the BC547A to BC550C, are lower voltage, lower current, general-purpose transistors in TO-92 packages, originating in Europe, that are often found in small-signal amplification and switching circuits of the type where the 2N2222 might otherwise be used.
The BC548 family, including the BC547A to BC550C, are low-voltage, low-current, general-purpose transistors in TO-92 packages, originating from Europe, that are commonly found in small-signal amplification and switching circuits where the 2N2222 might otherwise be used.