PIC Chip recommendation


Closed Thread
Results 1 to 4 of 4
  1. #1

    Default PIC Chip recommendation

    I need to control the speed of four electric motors. All four will have feedback hall effect style sensors. All four motors will need to match a speed dictated by one incoming PWM. Two motors are paired together. Each pair needs to be timed to each other based on the hall effect data. Sometimes the hall effect trigger wheel teeth will need to be totally opposite and other times teeth signals need to match.

    To summarize
    1 Incoming PWM to control speed for all four motors.
    4 incoming pulse signals from hall effects to measure rpm of each motor and compare timing of the paired motors.
    4 HPWM outputs to control motor speed.

    Ideally I would like to do this with one PIC. I have the room on the PCB for two PICS if there isn't one around that will handle the requirements.

    Thanks in advance.

  2. #2


    Did you find this post helpful? Yes | No

    Default

    Here is a basic schematic, the PIC on the schematic is just to show inputs/outputs.

    Quote Originally Posted by Tobias View Post
    I need to control the speed of four electric motors. All four will have feedback hall effect style sensors. All four motors will need to match a speed dictated by one incoming PWM. Two motors are paired together. Each pair needs to be timed to each other based on the hall effect data. Sometimes the hall effect trigger wheel teeth will need to be totally opposite and other times teeth signals need to match.

    To summarize
    1 Incoming PWM to control speed for all four motors.
    4 incoming pulse signals from hall effects to measure rpm of each motor and compare timing of the paired motors.
    4 HPWM outputs to control motor speed.

    Ideally I would like to do this with one PIC. I have the room on the PCB for two PICS if there isn't one around that will handle the requirements.

    Thanks in advance.
    Attached Images Attached Images

  3. #3
    Join Date
    Jan 2009
    Location
    Miami, Florida USA
    Posts
    637


    Did you find this post helpful? Yes | No

    Default

    Tobias,

    To find a chip that meets all of your project requirements use the Microchip Advanced Part Selector (MAPS)

    http://www.microchip.com/maps/microcontroller.aspx
    "No one is completely worthless. They can always serve as a bad example."

    Anonymous

  4. #4
    Join Date
    Jul 2003
    Posts
    2,405


    Did you find this post helpful? Yes | No

    Default

    My choice would be the PIC18F4431. Use 1 input capture to read the incoming PWM signal. Use a 2nd input capture to read 4 hall sensors through a 4066 quad switch. Just select the motor sensor to read with 4 outputs to the 4066 for channel select.

    Use the PCPWM module with 4 odd PWM outputs enabled for your 4 motor outputs. You can change the duty cycle for each of your 4 PWM outputs by writing to each duty cycle register. PDC0, 1, 2 and 3 as needed.
    Regards,

    -Bruce
    tech at rentron.com
    http://www.rentron.com

Members who have read this thread : 1

You do not have permission to view the list of names.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts