Hey,
I'm new to this forum so please go easy on me. A little about me: I'm a second year EE student, but oddly not spent much time actually making circuits, I just seem to be doing maths all the time. Anyway I like playing with electronic things and figuring stuff out.
I'm currently reacquainting myself with my breadboard and all these free TI chips I have by making a nice simple 555 PWM fan controller.
I have designed and tested a nice controller that allows for 11-96% duty cycle via a VR. All well and good. But I was thinking what about the fan start up. If the duty cycle is set low then the fan may not spin up and this is not what I want.
I've been trying to think how I could create a pulse to the fan for the 1-2s it needs to get moving but I'm stuck. I thought about having a monostable 555 that gives a pulse on power on but can't figure out how to get it to only give the pulse when the system is powered up. Is there a way with a monostable 555 or is there another way I'm completely missing that would be easier? I just need a pulse for 1-2s to help the fan spin up at the start.
I was wondering if anyone could help me? Thanks in advance.
I'm new to this forum so please go easy on me. A little about me: I'm a second year EE student, but oddly not spent much time actually making circuits, I just seem to be doing maths all the time. Anyway I like playing with electronic things and figuring stuff out.
I'm currently reacquainting myself with my breadboard and all these free TI chips I have by making a nice simple 555 PWM fan controller.
I have designed and tested a nice controller that allows for 11-96% duty cycle via a VR. All well and good. But I was thinking what about the fan start up. If the duty cycle is set low then the fan may not spin up and this is not what I want.
I've been trying to think how I could create a pulse to the fan for the 1-2s it needs to get moving but I'm stuck. I thought about having a monostable 555 that gives a pulse on power on but can't figure out how to get it to only give the pulse when the system is powered up. Is there a way with a monostable 555 or is there another way I'm completely missing that would be easier? I just need a pulse for 1-2s to help the fan spin up at the start.
I was wondering if anyone could help me? Thanks in advance.
Last edited: