I don’t get it
At the current levels that the IGBT will be operating in this application switching time, that interval in the linear region, will be rather important. Thus either serious heat sinking or fast switching will be important. And I am still concerned about that 3 volt VceSAT value. I may not be reading the data sheet right, that is what I think that I saw.yep it needed a pull down. Now it makes sense but driving it with a PNP is an improvement, you don’t need or want a pull down with a PNP You will need a pull up at the emitter of the PNP. You don’t need much current to switch the gate, start with a uA or two. It’ll be fine.
the gate of the IGBT has capacitance without the pull down, as drawn (with the NPN), the IGBT will not completely turn off when the BJT stops conducting.
I got the direction from the inference in post #36.@shortbus I don't recall stating clockwise or counterclockwise. Maybe I did. Nevertheless, for the sake of clarification; CW = brightening CCW = dimming. However, because of the way the circuit (post #1) is set up - I would expect that (eventually) the motor will spin faster with CCW. I think.
 OK, I finished reviewing all my posts. I didn't see anywhere where I said clockwise or counterclockwise. Maybe I missed something. But I don't think I ever said that.
But most blowers are under some type of restriction, but he is going to use this blowing into open air little or no restriction. Fuses in cars many(most?) times control more than one thing and are rated for all things being on at the same time. A better way to tell is to look at the motor leads, and figure the amp handling capacity of the wire.
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by Jake Hertz