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Hello there guys im looking for a way to connect and use a DC motor with a Servo controller such as the SSC32?

now given the fact that a Servo controller or driver has 3 pins, PWR GND SIG/PULSE now we know that a DC motor only has 2 wires PWR & GND.

now how can i connect this 2 together ? i mean i cant just put the PWR to PWR and GND to GND because as soon as we apply PWR to the board the motor will begin to actuate and we don't want that, we want the motor to run only when a signal is received by the SSC32 from the MCU in this case a Arduino.

this picture below depicts what i think i should be able to do BUT i could be wrong.

[![enter image description here][1]][1]

any suggestions would help in the matter guys, now this PULSE or SIG pin should be sending PULSE WIDTH MODULATED SIGNALS Correct ? pulses of voltages reading something like 3.3 or 5v correct? i mean i dont own something like a oscilloscope so i cant read this myself but maybe someone who does own one would have something to say.

should i be using this PWR pin in conjunction of a passive electrical component ? rather than doing what im thinking of doing by the picture above?

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Ok i been hearing everyone saying that you cant and you cant but no one is backing this up with reference images links or what not so it seems like im going to have to do just that in order to get closer to answer my own question or at least draw my picture clear question in detail for you all that keep saying "you cant !"

Here we have a Replacement Microphone Condenser and just like a DC motor it only has 2 outputs "power & ground"

enter image description here

Now

Here we have the same Microphone Condenser in its pcb setup WITH now 3 connections

enter image description here

Im not sure but it seems like theirs a way to convert a 2 output connection into 3 because now this above setup has a extra pin out that the actual mic it self did not have and in fact that extra pin is the how we are going to be able to listen once connected to the analog read on the mcu.

this extra wire is what i believe i can use to block the power to the motor from the ssc to STOP the power from turn the shaft and the only way it will let power thru is by the pulse pin becoming HIGH and only then will power be allowed to travel and actuate my dc brush motor.

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closed as unclear what you're asking by brhans, PeterJ, nidhin, Daniel Grillo, Scott Seidman Feb 14 '16 at 14:38

Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

  • \$\begingroup\$ Just for a moment, forget that you have this SSC-32 servo controller, and explain what you actually want to be able to do with/to the motor. \$\endgroup\$ – brhans Feb 9 '16 at 14:30
  • \$\begingroup\$ @brhans what i want is to have the motor run cw for a set amount of time then stop and when im ready OR a limit switch is press that reverses the motor ccw till another limit switch is trigger telling the motor to stop. all im doing is initiating the start of the cw the motor will stop on its own and later ccw itself according to those limit switches \$\endgroup\$ – Frank Feb 10 '16 at 18:50
  • \$\begingroup\$ the reason i want the ssc is because i know that it can handle nice current and can actuate multiple servos at once or even make group servo calls, so im just looking to do the same for the dc motors which is why i lead with the idea of putting the power wire of the motor in the pulse pin \$\endgroup\$ – Frank Feb 10 '16 at 18:53
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    \$\begingroup\$ Then @uint128_t's answer below is correct. You're trying to use a hammer to turn a screw. A servo controller is not an appropriate device to try to use to drive a simple DC motor. The servo controller's PWM output pin is a signal output. It does not and cannot provide power to drive a motor. \$\endgroup\$ – brhans Feb 10 '16 at 19:17
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    \$\begingroup\$ You CANNOT use your SSC to drive a DC motor. It CAN'T BE DONE. There is NO WAY to do what you're wanting to do. The SSC is the hammer you're trying to turn a screw with, the fork you want to use to eat soup, the knife in a gun-fight, the bicycle for a fish. \$\endgroup\$ – brhans Feb 11 '16 at 15:14
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You are trying to connect a servo controller (designed to power and control servos, which require a power supply and a PWM control signal) to a DC brushed motor (which is not a servo). (At least, I'm guessing a DC brushed motor from your image. Please provide specifications of your motor)

This is a bit like using a hammer to turn a screw. You are creating a problem where there needn't be one. Use a H-bridge to drive that motor. An H-bridge allows you to control speed and direction (and there are dedicated ICs that make everything simple and easy). And no, you can't use the PWM output of the servo controller to drive the motor, it's a logic output and connecting it to a motor will probably damage it.

You've provided no specs about your motor, but if it's smallish, a simple quadruple half-H driver (or double H driver, if you like your fractions reduced) like the SN754410 is popular among the DIY community (i.e. there are loads of tutorials online). If your motor requires more than 1A, then an L298, DRV8842, or a full bridge controller with discrete high current MOSFETs would be in order.


Edit (in response to OP's comments, as far as I can understand them):
As you may be aware, a servo has an integrated motor controller, position sensor, and control loop. So, you could build a servo control circuit (as well as a gearbox and pot) with your existing motor, and then your servo controller would drive your motor (because you would have turned your motor into a servo). Why you wouldn't use an existing off-the-shelf servo, I haven't a clue.

Here's another option: If you don't need bidirectional motor control (speed only), then you can connect the PWM output of the controller to a MOSFET, and switch the motor with it. You will probably want a low-side switching setup, to avoid having to boost the PWM voltage. This requires three components: a suitable MOSFET, a flyback diode, and a gate resistor.

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  • \$\begingroup\$ its a simple Brushed DC motor, thats it and as far as your comment about what the controller "keep in mind that a servo is nothing more then a dc brushed motor geared up with a pot" it also contains a adc or dac on its pcb and a PD type of control system if not a comparator and it is a Open loop so that the mcu can be used to control the shaft angle, im aware of the many IC's out there and i actually own plenty of this \$\endgroup\$ – Frank Feb 9 '16 at 5:40
  • \$\begingroup\$ but this is just me walking away from what i want to do so unless you can explain to me why this servo driver CANT do what i need OR how can i connect this type of setup im not sure your answering the question asked above \$\endgroup\$ – Frank Feb 9 '16 at 5:44
  • \$\begingroup\$ @Frank I'm having a hard time understanding your comments (punctuation and complete sentences would help me out a lot), but I have tried to expand my answer in response. \$\endgroup\$ – uint128_t Feb 9 '16 at 7:08
  • \$\begingroup\$ thanks for the edit, now as for what you was asking "If you don't need bidirectional motor control" YES i do need a bidirectional, hence the main question i asked "how do i wire this in such a way that i can signal the pulse to turn the motor on in one way and then when im ready stop the motor and hold its position and then rewind till i stop by sending the signal ? \$\endgroup\$ – Frank Feb 10 '16 at 18:46
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    \$\begingroup\$ You have edited your question to be a complete non-sequitur. What does an electret microphone have to do with motor control!? \$\endgroup\$ – uint128_t Feb 12 '16 at 19:04

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