I have a linear actuator and the only information I have is that it requires 1.7A and between 10-35V (from the online seller). Can I use the ULN2003 driver module that comes with the super starter kit or will it break the driver module?
The data sheet for the ULN2003 specifies the peak collector current at 500mA so I would say that it is not the part for a 1.7A device.
Please post a data sheet or other technical data for the actuator and perhaps we can help to find a driver.
Please read the how to get the most from the forum post. The post contains information on what we need to know in order to help you.
Thanks for your help. The name of the step motor attached to the actuator is 42HBS48BL4. I have attached the datasheet.
You need a stepper motor driver. I recommend that you look at the DRV8825 driver. The DRV8825 is good for 1.5A coil current without a heat sink and 2.0A with a heat sink. Your motor is rated for 1.7A coil current, but should work well at 1.5A. Set the coil current to less than maximum if the motor will perform satisfactorily. Doing so will let the motor and driver run cooler and extend their lives.
You must properly set the coil current limit proper before using the stepper motor. Failing to do so risks damage to the stepper and/or the driver. The Pololu page that I linked has instructions as well as this page.
The stepper motor basics tutorial may be of interest.
The specs on the datasheet are contradicting each other.
A stepper motor with 29 ohm coils can never draw 1.7Amp at 36volt.
Leo..
Thanks, I will look into all of that.
I'm not sure then, but the sticker on the motor does say that it draws 1.7A
That is the maximum rated continuous current per winding. The current draw depends on the supply voltage and the winding resistance.
Measure the coil resistance using your multimeter and tell us what you get. As mentioned, the data sheet is obviously in conflict and must have misprints.
That makes sense. Unfortunately, I don't have a multimeter right now.
A multimeter is an invaluable and indispensable tool for this hobby!
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I know now. I'll buy one as soon as I can.
Per the ULN2003 datasheet: "Outputs can be paralleled for higher current" November 2021 DocID5279 Rev 14 1/21. Looking at the curves with that type of current the Vsat will rise and the package will get very thirsty supplying that load. A reasonable MOSFET will properly drive that current without getting hot to the touch.
Do the calculations.
Typical saturation voltage at 1.7A with 7 outputs parallel is 1.2volt.
That's a dissipation of 1.7A * 1.2volt = 2.04watt.
Rth is 70C/watt, pushing the internal chip to 165C in a 25C environment.
That's above the absolute max.
That said, OP has a stepper motor, that is most likely 2.9ohm, not 29ohm.
That needs a proper current controlled stepper driver, not a ULN or mosfet.
Leo..
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