I have a computer with a small fan controller built into the case for the case fans. The DC brushless motors require a higher voltage to start than to keep running, so what I'd like is to mod the existing circuit to do that ie supply a full 12V (or close to it, it never actually needs 12V to start or run) and then drop back to the value as set by the controller pot.
The circuit is what I've traced off the controller and made assumptions about re the transistor type from what it's connected to. My question is would dropping a cap in where dotted act as I want ie turn the transistor on fully to get the motor going and then drop back to normal running voltage?
I've seen heaps of designs using linear regulators, or PWM, I just want some simple low cost thing, hopefully using what's already there. The fan load is small, a couple of hundred mA.
The circuit is what I've traced off the controller and made assumptions about re the transistor type from what it's connected to. My question is would dropping a cap in where dotted act as I want ie turn the transistor on fully to get the motor going and then drop back to normal running voltage?
I've seen heaps of designs using linear regulators, or PWM, I just want some simple low cost thing, hopefully using what's already there. The fan load is small, a couple of hundred mA.
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