I have made the hdd spin up up to more than 6000 rpms, actually I have limited the speed as I don't need much speed and I have made the lights stuff, and all It's done with the arduino.
I couldn't find anyone yet who have made all of this only with the arduino as all the info that I found about HDD POV clocks started with hdd that were able to spin, mine is only motor without circuitry at all so It means that Arduino is pulsing the motor, sensind the speed and making the lights stuff.
Here is the result yet.
The hands are moving and so...
Now that I am here, that I have go so far. I really need help...
I am planning to mount everything INSIDE the hard drive, an ARduino mini, the L293 who powers the motor and the TIP120 transistors the feeds the lighs , so everything.
The problem that I cannot solve is..
I am feeding the leds (12v) with a power source (12v)
I am feeding the motor with a different power source (4,7v) that is the perfect voltage, like that, the current is not going to infinite due to the low resistance (2ohms) between the hdd motor phases.
If I limit the current with my lab power bench to 1 am automatically the voltage drops to 5 or 4,7v (the perfect one) but I cannot drive the leds (12v).
So I really woud like to feed all with only a power source but I don't know how.
I have tried to feed all with 12v, straight to the leds transistors and trough a LM317 for the L293 but again the voltage drops or the current goes to infinite.
Someone suggested to PWM but I think that arduino is on his limits doing all this stuff already driving motor phases every 1500 microseconds and lights and interrupts and so, and the perfect PWM for a motor as I readed is 20khz so I don't think is possible to do it.
The second choice was to put a big resistor ( big means 2 or 5 wats ) to limit the current but I think that a lot of heat would be dissipated, and I am having problems already with the L293 piggyback getting VERY HOT so any help would be apprecciated.
I was even think to drive the motor with a Remote control ESC as everybody else and disregard all the programming work made about that, but now that I have spend weeks with this and the motor is working so smooth and as I said I donñt know anyone who have made all this with an arduino I really think that would be a pitty.
So If anyone suggest me a circuit to drive both things 12v leds low current ( like 100mAmps or less ) and the motor that works very good with 4.7 volts ( I think because the low voltage limits the current) at the same time and trying not to waist power in heat ( beause the plan is feed it all with a wall transformer ). I would really apprecciate a lot because I am totally lost.
Thank a lot in advance and best regards.