magnet control through PIC

[SterlingY]

Peterdeco1,

That's a very nice offer, but I can just order a few if I go that route. They are certainly cheaper than the other MOSFETS suggested.

Honetsly, I am beginning to think that MOSFETS may not be the way to go.

It may be determined by the magnets themselves. I've built a few, and now I've got some feelers out there to see what the pros think. I have seen small magnets driven by 6V that can hold 100lbs!!! I only need 1-2lbs. What I am getting at is that I should probably learn what my magnets will require and let that determine what the drivers need to be.

In the mean time, I'm still interested in playing with a multiport analog system and MOSFETS.

-Sterling

[mackrackit]

Another thing to look at is the switching speed. IGBTs normally will switch faster.

I use the FGA40N60UFDTU for motor control DC at 180 volts. These are out of you price range but... http://www.fairchildsemi.com/ds/FG%2FFGA40N60UFD.pdf

Also, the higher the voltage the less amps. (stating the obvious) So try to make a coil that will handle say 48 volts and then you might get by with a MOSFET if the switching speed is not to high.

Either way, do not forget a fly-back diode.

[skimask]

Peterdeco1,

That's a very nice offer, but I can just order a few if I go that route. They are certainly cheaper than the other MOSFETS suggested.

Honetsly, I am beginning to think that MOSFETS may not be the way to go.

It may be determined by the magnets themselves. I've built a few, and now I've got some feelers out there to see what the pros think. I have seen small magnets driven by 6V that can hold 100lbs!!! I only need 1-2lbs. What I am getting at is that I should probably learn what my magnets will require and let that determine what the drivers need to be.

In the mean time, I'm still interested in playing with a multiport analog system and MOSFETS.

-Sterling

Heck, try it out with the MOSFETs and the LEDs like I suggested above...get the firmware working right...swap in the magnets and the flyback diodes, and try it out.
As long as you've got the firmware working, if you accidentally smoke the PIC of a couple of MOSFETs, no biggie, at least the firmware is tested and works. Just have to work out the kinks at the business end...
and of course...I've just overstated the blatantly obvious...

[SterlingY]

Skimask,

You said you built a similar thing with LEDs. Would you happen to have the schematic?

-Sterling

[skimask]

Skimask,

You said you built a similar thing with LEDs. Would you happen to have the schematic?

-Sterling

Nope, built it off the top of my head with the datasheets, didn't really have time to draw it all out. But it really shouldn't be that hard in the first place.

Have you 'finalized' the end result yet? or do you just want to try it out with a bank of LEDs first or what?

'cause I'm thinking that you just get a PIC up and running, oscillator, a few buttons, maybe an LCD for diagnostics, and your bank of LEDs. Get them blinking the way you want, make the LCD work, make the buttons respond...then we can get working on applying some PWM to the LEDs. Since you'll have more than a couple of outputs to control, software PWM, timer interrupts, and a few other things will have to be used. Then after that's done, modify the outputs to run electromagnets instead of the LEDs by replacing the LEDs with the MOSFET/flyback/magnet combo.