BC548B vs BC548C

Hi,

I wonder what the significant difference between BC548B NPN and BC548C NPN is.
I want to use it to build logic gates, such as AND, OR, NAND etc. Is one better than the other or should I just buy one without worrying about that?

Thanks!

Jeroen

No differences that are obvious from the datasheet.
https://www.fairchildsemi.com/datasheets/BC/BC546.pdf
Same price in small quantities, 22 cents, down to 11 cents in 100 lots.

Either will be fine for making logic gates.

Thanks!

The trailing letter denotes the current gain. A is lowest and C is highest. It makes no difference if you are using them for a logic gate

Generally just go for the C gain class, they are the better devices in all parameters,
typically.

If you want fast logic gates these are not the faster transistors by any means, just
general purpose NPN. For logic things like leakage current is less important, but
minority carrier storage time is everything... The higher gain devices will have
a thinner base layer possibly which might make them a little faster to switch off.

The BC108 is the same device in a metal can.