PIC controller for a motor (PWM)

Hi,

I want to implement a speed controller for a motor (PWM). My problem
is that the motor needs 12V/10A which is too much for connecting it
directly to a PIC pin output.

I was thinking about using a relay, but I am not sure if it will work
due to the PWM high ON/OFF frecuency.

=BFWhat can I use? =BFDo you know any commercial PWM controller to use
with my PIC? =BFPrize?

Thanks ins advance.

"Vicente" <uchan@ono.com> wrote in message 
news:1192043001.152647.279620@57g2000hsv.googlegroups.com...
Hi,

I want to implement a speed controller for a motor (PWM). My problem
is that the motor needs 12V/10A which is too much for connecting it
directly to a PIC pin output.

I was thinking about using a relay, but I am not sure if it will work
due to the PWM high ON/OFF frecuency.

&#4294967295;What can I use? &#4294967295;Do you know any commercial PWM controller to use
with my PIC? &#4294967295;Prize?

Thanks ins advance.




Use the PIC output to drive the gate of a power FET.  If the control
is in the high side, use an optoisolator to drive the gate.

Don

On Wed, 10 Oct 2007 12:03:21 -0700, Vicente <uchan@ono.com> wrote:

>Hi,
>
>I want to implement a speed controller for a motor (PWM). My problem
>is that the motor needs 12V/10A which is too much for connecting it
>directly to a PIC pin output.
>
>I was thinking about using a relay, but I am not sure if it will work
>due to the PWM high ON/OFF frecuency.
>
>&#4294967295;What can I use? &#4294967295;Do you know any commercial PWM controller to use
>with my PIC? &#4294967295;Prize?
>
>Thanks ins advance.
 There are MANY motor speed controllers, this being one:
http://www.ifirobotics.com/victor-884-speed-controller-robots.shtml

Connect motor, 12V and a PWM signal, your good to go. I've used them
many times.

> 
> Use the PIC output to drive the gate of a power FET.  If the control
> is in the high side, use an optoisolator to drive the gate.
>

I've done that recently using FET's full bridge (left-right). I can send 
  schematic if you need a reference. Write me on: tomasz @ (remove-this) 
mikran pl

"DJ" <DJ@DJ.net> wrote in message news:fekmek$a28$1@opal.icpnet.pl...
>
>>
>> Use the PIC output to drive the gate of a power FET.  If the control
>> is in the high side, use an optoisolator to drive the gate.
>>
>
> I've done that recently using FET's full bridge (left-right). I can send 
> schematic if you need a reference. Write me on: tomasz @ (remove-this) 
> mikran pl

I have built many full bridges and single drivers with IRF3710 FETs.
Absolute MAX 100 Volts, 57 Amps.  The biggest problem with the
optos is the turn off times are several microseconds which leaves the FETs
in the linear region  long enough to generate heat.  Use a heat sink! 

> I have built many full bridges and single drivers with IRF3710 FETs.
> Absolute MAX 100 Volts, 57 Amps.  The biggest problem with the
> optos is the turn off times are several microseconds which leaves the FETs
> in the linear region  long enough to generate heat.  Use a heat sink! 

I am using BUX11 - pretty good and cheap. I am not using optos - never 
had any noise problems. Anyway I just slow down and speed up DC motor, 
not really regulate it's speed and most of the time FETs are either on 
or off instead of toggling and heatsink is not needed. Otherwise they 
will probably generate o lot of heat.

On Oct 11, 12:03 am, Vicente <uc...@ono.com> wrote:
> Hi,
>
> I want to implement a speed controller for a motor (PWM). My problem
> is that the motor needs 12V/10A which is too much for connecting it
> directly to a PIC pin output.
>
> I was thinking about using a relay, but I am not sure if it will work
> due to the PWM high ON/OFF frecuency.
>
> =BFWhat can I use? =BFDo you know any commercial PWM controller to use
> with my PIC? =BFPrize?
>

A motor, A 12V supply and A PWM signal =3D solution.

Karthik Balaguru

In message <felovo$1667$1@opal.icpnet.pl>, DJ <DJ@DJ.net> writes
>
>> I have built many full bridges and single drivers with IRF3710 FETs.
>> Absolute MAX 100 Volts, 57 Amps.  The biggest problem with the
>> optos is the turn off times are several microseconds which leaves the FETs
>> in the linear region  long enough to generate heat.  Use a heat sink!
>
>I am using BUX11 - pretty good and cheap. I am not using optos - never 
>had any noise problems. Anyway I just slow down and speed up DC motor, 
>not really regulate it's speed and most of the time FETs are either on 
>or off instead of toggling and heatsink is not needed.
Umm, isn't the BUX11 an NPN bipolar?
> Otherwise they will probably generate o lot of heat.

-- 
Clint Sharp

> Umm, isn't the BUX11 an NPN bipolar?
> 

I meant BUZ11 :-)