Need help with an idea

[MrSeaton]

I'm new to PICs. I have a parallax learning board and had an idea. I want to be able to controll a pc fan from the board and be able to adjust the speed of the fan. I don't have any grand scheme for this idea just wnat to know if its possible and if anyone else has done this.

Also has anyone built a PIC controlled voltage regulator?

Thanks
John

 

[mister_e]

can be done easily with a small device like those 12Fs or a nifty 10F. If you don't want to break your nuts, use a PIC with an internal PWM module like the 12F683. it have comparator, ADCs and a PWM module.

You read from the ADC and play with the duty cycle of the PWM.

 

[MrSeaton]

lol, I guess I need to have stated that I'm new to electronics too. After reading that I don't think standing up would help me either.

Thanks for the reply. I guess I will put some of those numbers in to google to find out what they are.

Thanks

 

[Overclocked]

A simple one would use a Low voltage Drop out regulator. The reason being is that you want that fan to get at high (or as close to 12V as possible on full speed). Take for example LM317- Its a perfect Regulator, unless you want to be able to go up to 10V or so. You would have to select a regulator for your needs, most high current regulators are pretty cheap ($1.00 to 1.50 or so, maybe less than a dollar).

The only thing is the Pot, But since you wont need that high of a wattage, it shouldnt be a problem.

 

[mramos1]

Not sure if Parallax has them (12F or 10F) on their boards. So yeah, MR_E went right over your head.

Does your PC not have fan speed control? You can get PC fans now that do this and play a little sound when they are too hot.

What you need for the project.

Input and Output.. I/O.

You need to know the temp (input). Google for thermistor.. That part will with a circuit tell the board the temp. Also see Nigel's joystick tutorial if you are running on battery.

Now that the board knows the temp. You need an output circuit to make the fan go faster or slower..

Let me know if this helps. But they make smart fans now. With a pot you can set and everything..

 

[Pommie]

Have a look at This Thread. It should answer many of your questions.

Mike.

 

[MrSeaton]

Not sure if Parallax has them (12F or 10F) on their boards. So yeah, MR_E went right over your head.

Does your PC not have fan speed control? You can get PC fans now that do this and play a little sound when they are too hot.

What you need for the project.

Input and Output.. I/O.

You need to know the temp (input). Google for thermistor.. That part will with a circuit tell the board the temp. Also see Nigel's joystick tutorial if you are running on battery.

Now that the board knows the temp. You need an output circuit to make the fan go faster or slower..

Let me know if this helps. But they make smart fans now. With a pot you can set and everything..

Oh no, Its not for my computer. I start small and come up with bigger ideas from all the smaller ideas I try. This one just happened to pop in my head. and thought that it would be neat to be able to build something that I could controll from my computer or program it to do some speed changes. It has no usefull purpose other than to show me that I can do it.

Thanks for the post