hi all
i want to drive 12v motor with
microcontroller

the microcontroller work by 5v and the motor 12v 4A how could i control the motor on/off with the microcontroller?

 

This is the shape of it. Place motor in position marked Rl and add a diode across the motor terminals with the positive end of the diode connected to the positive supply of voltage. Do you need help with the math?

 

Here's another one. Place the motor where it says, "relay".

 

Mosfet's are generally used now for interfacing with μp, no loading of the outputs and the on resistance is usually lower.
(the 2n7000 is only good for 600ma)
Max.

 

hi AAC Fanatic!...thanks for help
i dont have pnp transistor or logic mosfet! ..i have irf540 & irf640 mosfet....2n222a transistor & 3055 transistor and both npn! any idea?

 

Use the IRF540 in circuit a in post #2. Delete Rbe1 and Rb1, connect the gate directly to the uC. As stated before, put the motor in place of RL, and put a diode across the motor to protect the FET from spikes.

ak

 

Thanks for the help, guys. That was my last post last night and I was falling asleep.