# Difference between CD4017 and CD4017B

I have a choice between a CD4017 and a CD4017B.

I've also seen CD4026 and CD4026B.

What is the difference between these - is it a silicon revision or do they have different functionality?

-
The letters can vary depending on the company, but usually they are a minor difference between. Have you checked the datasheet? –  Kellenjb Oct 29 '10 at 14:38
But what datasheet? Many manufacturers make the same ICs. For example Fairchild I think make some CD series logic IC's. –  Thomas O Oct 29 '10 at 14:40
I can find the datasheet for CD4026B types and CD4026 types but they don't seem to reference each other. –  Thomas O Oct 29 '10 at 14:45
I have actually told my students this a few times. If the manufacture you are using doesn't provide a datasheet to you, then you shouldn't be using them. –  Kellenjb Oct 29 '10 at 14:56