Electronic speed control

[actionplus]

Has anyone tried building a speed control for a small radio control dc motor?

I have a Futaba radio which I am going to use for this project.
Any ideas where I cam start?

[Dwayne]

Has anyone tried building a speed control for a small radio control dc motor?

I have a Futaba radio which I am going to use for this project.
Any ideas where I cam start?

The 16F648A has a PWM on the B Channel.. this you can use for a motor control speed extremely easily... a N Type Mosfet and the pwm will allow you to do close to the entire range of the motor. (depending on the motor voltage).

Dwayne

[actionplus]

Will these be enough? So, using PWM output from the PIC should be enough to drive the MOSFET. Will a FET do?

[Dwayne]

Hello actionplus

actionplus >>Will these be enough? So, using PWM output from the PIC should be enough to drive the MOSFET. Will a FET do?<<

Yes it was enough...We used a 648A PWM... Got it working.. then attached a MOSFET to it, and ran a 12 volt model airplane motor and cycled the RPM's from 0 to 255 (255 being 100 percent). The Mosfet could handle 10 amps? and was about 1 dollar at the most... We only made one mistake... we accidently made a spark on one side of the circuit, and blew the PWM pin on the 648A...<chuckle> So use a Isolator when you are playing around with live ammo...We ended up using that 648A for other application that doesn't need that PWM port...<g>..

We also thought about using that same 648A chip for a LCD controller in 4 bit mode... Since the pin we blew was in the LSB of the LCD, and the LCD uses the MSB in 4 bit mode...We would assign the Data/Comand to pin B0, the Enable to B1, and ignore Pin B3 (our wonderful blownup PWM pin from our 12 volt sparky mistake <g>)

Dwayne

[actionplus]

Any recommendation on the MOSFET? Who did you guys use?

[Dwayne]

I believe it was the IRF540N

We had 3 or 4 different kinds...But I believe we used the
IRF540N...Because I ordered another 5 of them <g>
When I get home, I will find out for sure...Any should work...



Dwayne

[Acetronics2]

Hi, Dwayne

IF you want, I Already made one with 16F628...All features available ( radio and batt Fail-safe, opto-isolated, and Fet Driver !!!)

If you want to simplify the design, code is all right ... no bugs !!!

Alain

[actionplus]

Is there anyway you can send the info to my email address.
[email protected]

[bitmaniac]

Hi Acetronics

Why don't you publish your speed-control project
here so we aLL can benefit for this very good try of yours?
Keep up the good wotk

Thank you in advance

[Acetronics2]

Hi, bitmaniac

May be am I a bit shy ???

In fact too much projects to show...

I realised an entire line of accessoiries for Airplanes and Boats ...just for friends and my own use.

Talking about speed controllers... What do you think of a twin stack one W/ differential coupling, linear speed curve, and fiber-optics transmission to power Mosfets...and of course all possible securities... All in a 16F876

May be I prefer good friends to honors ...

Alain

[Dwayne]

Hello actionplus,

what you can do, is hook up your 648A chip... pin B3 is your PWM...

put about 20 k resistor from B3 to ground, and have that same pin to go the gate of the Mosfet...Then connect up your Mosfet drain to a 20+k resistor to positive (load for it) and put your motor in parallel with this resistor.

It should work like a charm...I will try to workup a schematic if you want.

Dwayne