
The key difference between components in the BC5xx line is their different tolerances for base, collector, and emitter voltages. Each of these variants is optimized for different voltage and noise levels, although they have the same basic physical structures as other components in the BC5xx line.

The BC547, according to its datasheet, has 8 variants.

All of the transistors in the BC5xx line are very similar, but each has slightly different technical specifications. The BC547 is one component in a line of NTN silicon transistors provided by ON Semiconductor. Featured BC547 variants in the Ultra Librarian search engine.
