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PWM board related



  • Hi just wondering, has anyone ever tried to move a motor > 6v through the PWM DC Barrel jack? was thinking if it's possible to move 12v motor.



  • @kencana-kesuma You should identify what motor you have in mind.

    There are two 100uF 10V electrolytic capacitors at the barrel jack (on Vcc_5V_P).
    The on-board PCA9685 IC basically is a 16-channel LED controller. Absolute max voltage and (sink) current on any output pin are 5.5V and 25mA.
    As you know a motor draws / consumes some current too.

    You should use an n-channel MOSFET or an NPN transistor as a switch between the IC's output and the motor . Please forget this idea.
    Only idiots like me start the experiments game with such simple circuits. Better ones will buy some official, certified motor driver board straight away. 😉



  • @György-Farkas said in PWM board related:

    PCA9685

    PCA9685 as used in the PWM "signaling-only" board needs a real and suitable "motor driver" board to drive OP's specific motor.



  • @ccs-hello Any output of PCA9685 can sink up to 25 mA at 5V. So this PWM "signalling-only" board can drive 16 directly connected LEDs >> 16 x 25 mA = 400 mA.



  • OP is talking about driving motor(s), not LED (sink 25 mA max per channel.)
    What motor can be driven only using 25 mA? Back EMF, stall current, etc.??? Motor driver board is the way.



  • @ccs-hello said in PWM board related:

    OP is talking about driving motor(s), not LED

    Yes. Please notice only OP wants to connect a motor to the PWM Expansion - not me.

    (sink 25 mA max per channel.)

    400 mA in all! It's not bad for this degraded "signalling-only" board.

    What motor can be driven only using 25 mA?

    Who knows? I'd be curious too.
    See also the first paragraph of PWM Expansion

    Back EMF, stall current, etc.??? Motor driver board is the way.

    flywheel diode, snubber, no-load current, ...
    A logic level n-channel MOSFET (or an NPN transistor) and a 1N400x diode are not enough - all we need is motor driver board! 🙂



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