h-bridge speed control dc motor

[minisan]

hi, i am a totally new in microcontroller but i am interested in learning it. so i m planning to carry out my first project, ie to control the speed of a 12Vdc motor using a PIC16F877A microcontroller. i understand that i need to have a programmer to program the microcontroller. where can i get the schematic for bootloader? how do i determine the current i want during no-load and full load? that means i need to calculate the value for the resistors? anybody can share with me the schematic circuit to do the speed control dc motor by using h-bridge with microcontroller as kickstart since i am totally dont know about it. hope somebody can help me... thanks in advance!! =)

 

[Jack// ani]

for bootloader see this nice site....www.microchipc.com.
Regarding h-bridge...you need LD293 chip..to control direction and speed of the motor. If you want to control..the speed only, a transistor or mosfet will do that.

Hope this helps

 

[minisan]

if i choose to built the h-bridge myself, does it just need 4 mosfets and a dc motor like what we alwiz draw about the h-bridge diagram? why most of people prefer to choose 12V dc motor, not other like 9V etc(for low voltage application)? which type of mosfet is suitable?
regarding the bootloader, must we connect to hyperterminal in order to use it? between bootloader and home made programmer, which one is easier and better? thanks!!

 

[Jack// ani]

Yes....you will need 4 mosfet, see this link **broken link removed** Choice of mosfet depends on current rating of your motor, which you haven't mentioned!! Regarding bootloader...you don't need hyperterminal, they have their own software...see this
https://www.microchipc.com/PIC16bootload/

Hope this helps

 

[minisan]

thanks for the information...
btw i wish to know which PIC is suitable for this purpose? does PIC16F84A has enough pins for that if i want to further enhance it into 4-quadrant dc motor with speed control?
thanks in advance...

 

[Jack// ani]

PIC16F84A is more than suffice!!

 

[gidimiz]

Hi,

Microhip has very good support for what you want to do, have a look at:
www.microchip.com/motorcontrol

Also, see the App. nots in the main web site like for application notes.

Good luck.