In this episode Shahriar demonstrates one of the simplest magnetic levitation circuits. First, the basic concept of magnetic levitation is examined. Two different methods of detecting the location of the levitating object is presented and the Hall effect sensor method is chosen. A semi-digital overall system is implemented where a PWM control IC is employed to control the magnetic field strength. The block diagram and functionality of this IC is presented. Finally, the schematic of a dual-Hall effect sensor solution is presented. The circuit is built and tested in both open-loop and close-loop configuration. Magnetic levitation is demonstrated with the capability of adjusting the levitation location. The schematic of circuit can be downloaded here and the electromagnet can be purchased from here.
Hi Shahriar,
Where did you obtain the KA7599? I have only been able to find the 17599 from Maxim which has extra features.
We are putting one together for Bring Your Kids To Work Day and think they will find it really exciting… will definitely recommend your blog in the handouts!
Thank you!
-Yue
Hi, I built this setup almost exactly the same. I have the same electromagnet and circuit components. The circuit components appear to be working as expected, but so far I haven’t been able to get it to levitate. It is acting unstable no matter where I put the magnet. It tries to levitate, kicking the magnet on and off. You can feel it, it is just never getting into the duty-cycle zone.
I am wondering if you had to try different power levels? Also, how sensitive is the setup to different magnets as my magnets are not exactly the same? I am not sure if I need different magnets, but they are very similar, perhaps a little smaller in diameter.
P.S. I have had some success by removing R2 and R8 (in the pdf schematic) although it is a bit unstable.
Shahriar, all your videos are great, I particularly enjoy them because you go into a lot of detail that other “bloggers” don’t. You also cover some interesting topics that I would never have thought about before. I cannot wait for the PLL video, should prove to be very interesting.
Keep up the good work!
Regards,
Jovian.
Great video, I’m definitely going to do this experiment with my son… I’m buying a new set of screwdrivers, I notice you have a nice set… where did you get them? And I like how you have them organized. Thanks Dan
Awesome video!
I am wondering why you connected the Vfb and the reference voltage from the potentiometer to both inputs of the IC? Is that necessary for correct operation?
Great video! A very interesting and cool topic that I hope to experiment with when I get some free time. I’m looking forward to a future PLL video as well.
-Will