special transistor question

N

Njguy

Member

• Jun 24, 2012

• #1

Does anyone know of a type of transistor that when power is supplied to it, it switches on, but when the input power is off, instead of turning the transistor off, it switches on a different output? I know I'm not explaining this with appropriate terminology, but it's the best I can do.

 

crutschow

Well-Known Member

Most Helpful Member

• Jun 24, 2012

• #2

Tell us what you are trying to do, not what part would do this mysterious function.

 

N

Njguy

Member

• Jun 24, 2012

• #3

I'm trying to come up with a simple dc motor controller with two phases.

 

cowboybob

Well-Known Member

Most Helpful Member

• Jun 24, 2012

• #4

Are you describing a "power ON - forward motion, power OFF - reverse motion" situation?

If so, one transistor can't do it. Try a solid state DPDT relay.

 

N

Njguy

Member

• Jun 24, 2012

• #5

Yeah I am describing a power on, and power off = solenoid polarity switching situation with a hall effect sensor. I wanted to do it with as few components as possible.

 

crutschow

Well-Known Member

Most Helpful Member

• Jun 25, 2012

• #6

I'd go with cowboybob's suggestion.