Paul & Sabrina's cheap DIY 144v motor controller

[esoneson]

Paul,

AtMega cost?

Eric

[MPaulHolmes]

It's $2 or so. haha! In bulk, I've seen it on ebay for $1.50.

[MPaulHolmes]

I finished the change to the circuit so that it takes a 2 wire pot instead of a 3 wire pot. Now, it's compatible with a plain old ordinary PB-6! Or for you cheapskates out there, you can still use a $2 5k pot from Radio Shack. Just ignore one of the 2 end prongs. Just use the middle one (washer) and one end prong. I estimated that it would take 1 hour to design and implement the new circuit, which uses an LM317. It took way longer! I am a slow poke! Dang me dang me, someone take a rope and hang me. hang me from the highest tree, darling won't you wait for me?

Note: I haven't tested it yet. I'll do that later tonight or tomorrow.

Stuff's acomin' in the mail. I's real excited. Real, Real excited.

[MPaulHolmes]

Originally Posted by brihoo2k

I know that I haven’t really posted in here but I have read until my eyes have bled, and this is the sweetest thread.

That rhymed.

[motor_control]

Originally Posted by MPaulHolmes

I finished the change to the circuit

Try free version EAGLE - CadSoft Online: EAGLE Layout Editor

[brihoo2k]

Originally Posted by MPaulHolmes

That rhymed.

Yeah it wasnt suppose to rhyme. But I do it all the time

[MPaulHolmes]

Originally Posted by brihoo2k

Yeah it wasnt suppose to rhyme. But I do it all the time

Stop that rhyming, now I mean it! Anybody want a peanut?

[MPaulHolmes]

The new 2 wire throttle works really well, however...

The datasheet includes both the LM117 and LM317. It said it keeps 1.25v between Vadj and Vout (for the LM117 AND LM317!!!), but it actually keeps 2.0v between Vadj and Vout (for the 317). Ya, that would be good info to include in a datasheet. So, I chose resistors accordingly, for the 1.25v, which made my 0-5v input to the DC-DC converter around 0-6.3v! I had prepared for just such an emergency in the software, to shut down if the voltage was over 5v to the throttle input on the chip, however, in my debugging process, I was trying to wire the throttle input of the chip to ground during testing, but I wired a different pin (I think it was AVcc) to ground, which as they used to say on Ghost Busters, is a bad thing. Well, I need a new ATMega8, which is coming in the mail. Makes me mad! WAAAYYYYYYY DOWN DEEP! I need some new flame retardant clothing, cause I'm a steaming pile of flames and anger!

Well, either the datasheet was wrong about those lm317's or the lm317's I ordered from Ebay are a different type.

[bennelson]

Hey Paul,

Keep up the good work.

Remember, keep frying all the cheap parts so you get it out of your system by the time you get the expensive parts.

I came up against a lot of frustration working on my Electro-Metro when I would physically wreck something. At least now I know some local guys with welders and things to help me.

And you have all of US out here on the web!

(PS - I hit 47 MPH in the Metro today - I am hungry for more amps and volts!!!)

[RedRod]

I'm sorry if i missed it but is there one updated schematic of the controller? I'm following this thread for a while and i missed the voltage and current connection to the atmel8 controller.