control motor speed with byte

Discussion in 'The Projects Forum' started by Gadersd, Jul 15, 2013.

  1. Gadersd

    Thread Starter Member

    Dec 8, 2012
    For my next project I am going to use a microprocessor to control the speed of four motors. The microproccessor will output a byte representing the speed of a motor. I need a circuit that will take a byte and either change the voltage or current to the motor to control its speed. I first thought of feeding the outputs of the microprocessor into a bunch of different sized resistors with diodes and connecting them together to control the current that goes to the motor. I might post a schematic of this later. I am pretty sure this is not the best way to do this. Any ideas?
  2. crutschow


    Mar 14, 2008
    You can use a D/A converter to convert the digital signal to a voltage. The voltage can then control the motor current or voltage, whichever you want.

    D/A's are available in many different number-of-bit resolutions. If you only are outputting one byte, then an 8-bit D/A would suffice.
  3. shortbus

    AAC Fanatic!

    Sep 30, 2009
  4. tubeguy

    Well-Known Member

    Nov 3, 2012