3D Printering: Trinamic TMC2130 Stepper Motor Drivers

Adjust the phase current, crank up the microstepping, and forget about it — that’s what most people want out of a stepper motor driver IC. Although they power most of our CNC machines and 3D printers, as monolithic solutions to “make it spin”, we don’t often pay much attention to them.

In this article, I’ll be looking at the Trinamic TMC2130 stepper motor driver, one that comes with more bells and whistles than you might ever need. On the one hand, this driver can be configured through its SPI interface to suit virtually any application that employs a stepper motor. On the other hand, you can also write directly to the coil current registers and expand the scope of applicability far beyond motors.

The TMC2130 SilentStepStick’s top side with SPI headers and heatsink.

Last month, we took a closer look at microstepping on common stepper driver ICs, but left out the ones that we actually want to use: the smart ones. Trinamic provides some of the smartest stepper motor drivers on the market, and since the German hacker store Watterott released their SilentStepStick breakout boards for the TMC2100 and TMC2130, they are also setting a new standard for DIY 3D printers, mills and pick-and-place robots. I recently acquired a set of both of them for my Prusa i3 3D printer, and the TMC2130 with its SPI configuration interface really caught my attention.

The TMC2130 SilentStepStick should not be confused with the — far more popular — TMC2100 variant. As the name suggests, it comes as a StepStick-compatible breakout board, and just like it’s famous sibling, features a Trinamic IC on the bottom side of the little PCB. Several vias and copper spills conduct heat away from the IC’s center pad, allowing a heatsink on the top side to effectively cool the driver.

The bottom side with the stand-alone mode solder blob jumper next to the IC.

However, unlike the TMC2100, this one won’t let your motors spin right away. You’ve got two options: Hard-wire it in stand-alone mode, which practically turns it into a TMC2100, or hook up to its SPI-interface and dial in if you want your stepper motor shaken or stirred. In fact, plentiful configuration registers make the TMC2130 an extremely hackable chip, so I’m not even thinking about bridging that solder jumper on the SilentStepStick’s bottom side that activates the stand-alone mode.

First Steps

Wiring the TMC2130 to a classic RAMPS 1.4.

As said, before the driver does anything, it wants to be configured, and it’s worth mentioning that all configuration registers are naturally volatile, so if I want to use them in my 3D printer, I need to configure them as part of the printers startup routine.

The RAMPS 1.4 on my 3D printer breaks out the hardware SPI interface of the underlying Arduino through its AUX3 pin header, along with two additional digital pins (D53 and D49), which I used for the cable select signals. After crimping a cable to connect two TMC2130’s to the AUX3 header, I could start digging into the software part.

Watterott provides an example sketch, which writes a basic configuration to the driver’s registers and spins an attached stepper motor. Great stuff, but the datasheet describes 23 configuration registers waiting to be finely tuned, and 8 more to read diagnosis and status data from. So, I wrote a little Arduino library that would make the numerous configuration parameters available in a more practical way. From there, I could just include my library into the Marlin-RC7 3D printer firmware I’m using. Luckily, the current Marlin release candidate already features support for TMC26X drivers, so I could reuse some of its code to put together a Marlin fork that includes 59 of the TMC2130’s parameters in its define-based configuration files. And then, I could take the little buddies out for a spin.

First steps on a RAMPS 1.4 on a somewhat-uino (sorry Massimo). The testing-contraption to the left is a NEMA 17 stepper motor attached to an encoder.

Taking Them For A Spin

With the hardware set up and the software working as supposed, I ran a few sanity tests: toggling parameters on and off and checking how the driver’s behavior changes during printing. Since the TMC2130 let’s you tune almost everything it’s doing, that’s a good first step that helps to eliminate some variables and picking others that are worth a deeper look. Most of the settings can be changed on the fly and mid-print, however, not all parameters can actually be safely changed while the motors are running.

The TMC’s in service. I’m using the SPI-configurable TMC2130’s (silver heatsink) for the X- and Y- axis. The Z-axis and the extruder feature the TMC2100 (black heatsink). All of them are sitting on additional free-runner diode protection shields.
An excerpt of Trinamic’s thorough quick start guide.

To actually tune the drivers for a certain application, Trinamic provides a quick start guide in the datasheet, as well as detailed information on each parameter, and on how they interact. Basically, the first step is adjusting the RMS coil current by using the onboard potentiometer on the SilentStepSticks. Then, we need to chose the analog input pin as a current scaling reference to actually make use of the potentiometer. The mentioned library lets me do this through a simple method:

myStepper.set_I_scale_analog(1); // 0: internal, 1: AIN

The running and holding current are the first real parameter that should be tuned, with the running current typically at the desired maximum current, and the holding current at 70% of this value. The delay between a stillstand and the transition from running current to holding current can be adjusted between 0 and 4 seconds, and for now, I set it to 4 seconds, practically disabling the current reduction while the 3D printer is running. The three values share one write-only register, so the corresponding method call looks like this:

myStepper.set_IHOLD_IRUN(22,31,5); // [0-31],[0-31],[0-5]

and sets the running current to 100% (≙ 31), the holding current to about 70% of this value (≙ 22), and the delay between the two to 4 seconds (≙ 5).

I want torque, so I can leave stealthChop disabled. The datasheet suggests some starting values for configuring the chopper’s off time and the comparator’s blank time settings, but since it’s a key tradeoff between switching noise and torque, it makes sense to iterate through other values as well. The library methods for the two values look like this:

myStepper.set_tbl(1); // [0-3]
myStepper.set_toff(8); // [0-15]

And finally, I need to pick a microstepping resolution and choose if I want to make use of the 256 microstep interpolation feature, covered later in this article:

myStepper.set_mres(32); // {1,2,4,8,16,32,64,128,256}
myStepper.set_intpol(1); // 0: off, 1: interpolate

I have yet to walk through the entire tuning procedure, which includes monitoring the coil current on the scope and eliminating distortions in the zero crossing, but I’m getting a clue of the driver’s potential.


It’s maximum continuous RMS current of about 1.2 A per coil (at least in the QFN package on the SilentStepSticks) lets it look like a low-current driver, inferior to the common A4988 and DRV8825. In practice, it outperforms both of them by making intelligent use of a 2.5 A peak current margin. This gives it more than enough torque for 3D printing. I wouldn’t recommend pushing them over 0.9 A RMS though since the IC will momentarily pull more current if it needs more. For SilentStepStick users, that’s a Vref of 0.88 V. Through the SPI-interface, you can choose how much current you want to send through the motor coils when it’s spinning, and when it’s idling. You can choose after how many seconds it will start to decrease the current to a lower holding current when the motor is in standstill, and then to an even lower idling current. And, of course, you can also set it to squeeze out the maximum juice for everything.

Shifting The Gears

Where it starts getting interesting are settings like the high-velocity mode. Above a configurable velocity threshold, the driver offers you to automatically switch the chopper to a faster decay time to squeeze out some extra speed. You can also literally shift the gears by letting the driver internally switch from microstepping to full-step mode once it’s up to speed.


Choosing a finer microstepping resolution smoothens the stepper’s movement, reduces vibrations and sometimes even increases the positioning accuracy. However, it also multiplies the load on the microcontroller, which has to churn out 16, 32 or 256 times more step pulses per second. The TMC2130 lets you pick an input resolution between 1 and 256 microsteps per full-step, and then gives you the option of interpolating the output resolution to 256 microsteps. This allows for smooth operation even on increasingly retro 8-bit AVR motion controllers, which cannot deliver high step frequencies. Also, by configuring the TMC2130’s interface to double-edge step pulses, you can at least double the step frequency at almost no cost. Given that the modern IC still features the classic step/direction interface and even an enable pin, those few additional features actually make it a sweet drop-in upgrade for less-recent CNC and 3D printer electronics.

Noise Reduction

The TMC2130’s datasheet promises undistorted output with stealthChop.

Just like the TMC2100, the TMC2130 features two efficient and silent drive modes: spreadCycle, and stealthChop. The former delivers high torque at relatively low noise emissions, the latter one is almost inaudible, and there are quite some confusions out there about whether or not that affects torque: Some users experience dramatically reduced torque, while Trinamic’s paper on the issue states the opposite. Below 300 RPM (typical 3D-printing speeds), stealthChop should not affect torque at all. According to Stephan Watterott, double- and quad-stepping, as used in most 3D printer firmwares, could be to blame here.

Either way, the flexible TMC2130 allows you to tweak the chopper yourself to find the right balance between torque, noise, and efficiency for your application. One of the more noteworthy options in this regard is the possibility of randomizing the chopper’s off time. Since most of the audible noise is released due to dubstep the chopper busily switching the stepper motor’s coils, this option spreads the noise over a wider frequency range to subjectively silence the stepper motor.

Stall Detection

The TMC2130 notices when the motor is stalled and losing steps by measuring the motor’s back EMF. Along the way, it counts missed steps, allowing the controller to compensate for otherwise irreversible step-loss. It’s also a great way to react to obstacles rather than running into them full-force and, of course, the feature can be used as an axis endstop. Trinamic calls this feature StallGuard, and just like anything else in this motor driver, it’s highly configurable.

Direct Mode

microstepping_exlained-01Instead of letting the motor driver handle everything for you, you can also choose the direct mode. This mode practically turns the driver into a two-channel, bipolar constant-current source with SPI interface. You can still use it as a motor driver, but the possibilities reach far beyond that. It’s worth mentioning that the datasheet might be a bit confusing here, and the corresponding XDIRECT register actually accepts two signed 9 bit integers (not 8 bit) for each coil and operates as expected within a numeric range of, naturally, ± 254 (not ± 255) to vary the current between ± Imax/RMS..

The Takeaway

About half a year after the release of Watterott’s breakout board, the potential of smarter stepper motor drivers piqued the curiosity of the 3D printing community, but not much has happened in terms of implementation. Admittedly, it takes some effort to get them running. If you’re still busy dialing in the temperature on your 3D printer, you surely don’t want to add a few dozen new variables, but if you’re keen on getting the best out of it, the TMC2130 has a lot to offer: low-noise printing, high-speed printing, print interrupt on failure and recovery from lost steps. Because the driver IC is so hackable, it’s clearly intended to be tuned in to accommodate specific applications. Throwing it on a general purpose test bench probably won’t yield meaningful, general purpose results.

I hope you enjoyed taking a look at a smarter-than-usual stepper motor driver, as one of the new frontiers of DIY 3D printing, and as an interesting component with many other applications. If you’re thinking about experimenting with this IC or breakout board in your 3D printer, feel free to try my Marlin fork to get started. If you’re building something entirely different, the underlying Arduino library will help you out. Who else is using this part? I’ll be glad to hear about your ideas, applications, and experiences in the comments!

21 thoughts on “3D Printering: Trinamic TMC2130 Stepper Motor Drivers

    1. I think the TMC2130 has this feature, but unfortunately the SilentStepStick doesn’t break out the IC’s encoder pins. I’m exploring ways to test the dynamic positioning accuracy using the encoder, but for now, I’ve just been using the encoder to verify proper operation of the library.

        1. Well, it kind of breaks them out to tiny configuration pads (equipped with zero ohms), so with help of a bit of magnetic wire you should be able to use the encoder commutation feature on the SilentStepSticks as well. But I’m not sure if this is meant to increase resolution.

      1. I’ve emailed Trinamic about the vague notes in the datasheet that allude to encoder support. They say to basically forget about it, it doesn’t really apply to the TMC2130, it was either a datasheet copy and paste error, or something they put in for a specific customer but either way, they assured me it wasn’t possible on the TMC2130.

        Bloody shame, really.

        1. Interesting, I emailed them, too, and received an entirely different response: They said the feature were some sort of free-running mode. Once a full-step encoder is attached and the configuration flag is set, the stepper motor would just spin as fast as it can (basically, what’s stated in the datasheet). I’m still clueless about what this would be good for..

          Either way, if you want to close the loop, you’ll have to do it externally. Too bad.

  1. Damn, it’s been awhile since I commented on here, but I’m loving the stepper driver stuff lately. Would love to see the series continue, with super in depth analysis and test methodology. Not enough of this stuff exists on the open web right now IMHO.

  2. Well the “low” current really isn’t a problem in my opinion. Running a motor at the current shown on the label cause them to get alarmingly hot. I think it’s either an absolute maximum or the current on my RAMBo is really an RMS figure. I think I’m running my motors at half the current shown in the motor specs and getting excellent results from them. FWIW, I’m not actually getting any more than 1A out of an A4988, much more and they can start acting up.

  3. Great article! I’d like to know how do these compare to the other steppers in the recent comparison?

    I also want to see someone do something with these and encoders, hope to see it here soon!

    1. Thanks!

      As said, these drivers are meant to be tuned to a certain application, with their performance depending on a few dozen configuration parameters. Throwing general purpose tests at them (like the positioning test last month) probably won’t yield a meaningful result.

      But I think we need to look into this encoder commutation feature a bit more.

      1. First off, you’ve done an amazing job on these stepper driver articles. Awesome work!

        While it’s true that the TMC2130 offers lots of room for configuration, I think the configuration that most 3D printer users would be interested in would be the TMC2100 in spreadCycle mode and 1/16 microstepping with interpolation to 1/256 microstepping. I know that a *lot* of people would be interested in seeing this configuration compared to the other stepper drivers you wrote about in the other article. Is that something you would be willing to consider?

        Thanks for these articles and keep up the good work!

  4. “According to Stephan Watterott, double- and quad-stepping, as used in most 3D printer firmwares, could be to blame here.”

    Can I have a source link on that information please ? I’d like to read the full text of what Stephan W. says about this.


  5. Hi Moritz,

    as a complete noob running two printers at this time, you encouraged me to finally rebuild / modify my Leapfrog Creatr and Ultimaker Original +. Without you article, I would be totally lost I guess. :-)

    I have to modify them, because I really get sick of all the noise they make, so I decided to buy two RAMPS 1.4 sets as well as the TMC2130 modules for all 3 axles (including the protection boards) from Watterott.

    Beside all the other problems I have now (electrical wiring of RAMPS etc) I have one critical question:

    In my RAMPS 1.4 packages, a full graphic display was included to connect to the board. The SPI interface you mentioned here would be already blocked by the adapter for the display. Can there be multiple devices on that SPI??
    I do not want to leave out the display although I will be using Octoprint as well.

    If there is a possibility, do I have to regard any specialties?

    Thank you so much in advance.


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