Hi!
Should help a little.
A bipolar stepper controller schematikus npn transistors drawing of what kind of use?
Thank!
They provide a complementary signal to the control input, that is they ensure that the logic level at 1in is always the inverse of that at 2in so current is always flowing one way or the other in the motor.
Thank you!
Can you tell us a TO-220 cased example of what specifically can I apply here?
Sorry I don't understand.
A TO-220 is a package that manufacturers put transistors in.
Yes.
Can you an example of what can be used into the circuit?
Your English is very difficult to understand.
That circuit can use any sort of general purpose NPN transistor, like a BC183 or a 2n2222.
Was that the question?
Yes.
Thanks.