Stepper Motor Driver Ic L297 Driver
- Stepper Motor Driver Ic Datasheet
- Stepper Motor Controller Schematic
- Stepper Motor Driver Ic L297 Driver Manual
You are welcome! The sense resistors are not needed in this design (replace with a wire), so long as your motors will not draw 3A (transient) and 2A steady state. Otherwise they are needed to limit the current through the motor. The full current that goes thru the motor goes thru these resistors!But it would be very fun to have them and also connect pins 1 and 15 to the Arduino's analog inputs (make sure the voltage at these pins. Are you using the multiwatt package?It can dissipate 25 watts (per the spec) but you've got to add a heat sink. That's what the tab with the hole is for on top.
You can buy one or get a piece of copper flashing or a brass sheet from a hobby store and drill a hole in it. Attach with screw and CPU heat-sink attachment paste.You will want that full 24 volts to push through material.But yes until you're really cutting material, its a good idea to run at 5v. Less chance of a mistake or a accidental short wiping out your Arduino.BTW, its not a good idea to use the Arduino wall wart and power supply to drive motors this big - use a separate one and connect their grounds. I think you misunderstood me. The sense resistors aren't really meant to limit the current but you could put resistors there if you had to. But if you do you are just wasting power. The motor's internal resistance should do the job (check the resistance with a ohmmeter if you feel the urge).
But double check that its really rated 24V 1A. And while you are verifying that, also check the motor spec to see if it can 'hold' at that or just be pulsed. Mostly it is solenoids that can't hold, but best to read the motor's spec.Too hot to touch is not necessarily too hot. If I remember the spec the chip is rated up to 135C so that's much too hot to touch.
Stepper Motor Driver Ic Datasheet
You know without a heat sink your PC's CPU can be used a the world's smallest frying pan (just before it melts itself down - actually that's old school - they have internal thermometer and just turn themselves off now).The chip is rated to 50V, 2A continuous so your motor sounds well within its bounds.I'd measure the current thru the system (put an ammeter in series where the sense resistor would go) to make sure it is. AnonymousHi,I think (but I am not sure) it can be hold at 24V 1A bipolar and 1.2A unipolar.Here are my motors:read in the datasheet(voltage: DC24Voperating current: 1.2A/phase, 2-phase energization（full-step）I will measure the current this afternoon or this week-end.No, my motor is not warming at 5V but well at 12V I think.Thanks for your help;).
Stepper Motor Controller Schematic
Putting too much current through a coil can overheat it, melt the insulation and burn out your motor.You can calculate the maximum or steady state current using Ohm's law.However, the nature of an inductor is that it resists changes in current. Basically, the creation of the magnetic field slows down the current passing thru the coil and the breakdown of the field pushes extra current thru the wire.So if you had an oscilloscope you would find that when you first apply a voltage, the current rises slowly, plateauing approximately where V=IR suggests it would.Since the current rises slowly, it is ok to apply a very high voltage in short bursts - if you do this the current never gets high enough to burn out the motor. And of course, to MOVE a stepper motor you energise the coils in alternating fashion - that is, you apply voltage in short bursts!In fact, it is not only ok to use high voltage, but 'better' because the higher the voltage the faster the magnetic field builds. And the speed of this magnetic field buildup determines the maximum speed the motor can spin.So I'm guessing that I was right to ask you to check the 'holding' vs 'running' voltage. Given what you've told me, I think that 24 volts is the maximum pulsed voltage you should give the motor. And I think that the maximum holding current is 1A (probably around 7-8 volts).
Stepper Motor Driver Ic L297 Driver Manual
But I'm no expert on your motor.To be safe, use 7-8 volts - whatever gets you 1A steady state. The downside is that the maximum rotation speed will be lower. There is no need for PWM, normal digital IOs will work fine.
Look, any repetitive on/off signal is 'PWM'. The Arduino's 'PWM' pins do it really fast, but this class does it just fine with normal digital pins. A stepper motor is an incredibly slow device compared to a 16 MILLION instruction per second CPU.The L298 essentially amplifies a small signal into a powerful one. But there is no conceptual abstraction. The L297 has some smarts. It converts a concept like 'go forward' into the appropriate signals to move the motor forward. Basically it is a hardware version of this class.Personally, I would not use the L297.
Its really for devices that don't have a CPU, IMHO. As you gain sophistication, you will find that you can extend this class to drive the motor through precise changes in acceleration or velocity, and synchronise these motions with that of the other steppers. HiFirst, Thanks for this great stepper driver code.It is the first one that I it work a little bit for me.I'm trying it with several steeper motor.With a 6 wire unipolar all 4 phases don't seem to be well drived.I carefully read your binary sequence code and I don't find this sequence:000001wich seem to be the good one to drive my 6 wire unipolar motor.but this one101001I think this will for using unipolar as bipolar or simply bipolar motor.I try to change it but I don't completly understand why you do a logical sum!I'm new in C Languages,May you help me?