Hello Machine Bros!
Today we are going to give you a basic guide on 3D printer stepper motor drivers.
The drivers are a fundamental piece in the operation of a 3D printer since, through them, the microcontroller controls the stepper motors that are responsible for carrying out the movements in the different axes of the 3D printer.
In our new 3D printer comparison tool, you can see which driver a 3D printer has, whether they are the new silent TMC2209 drivers, or the old A4988 drivers that generated a lot of noise. Keep in mind that, in some cases, the manufacturer does not provide information on the drivers of their 3D printers.
Without further ado, let’s start by talking about what a stepper motor is.
What Are Stepper Motors?
They are electromechanical devices that convert electrical impulses into discrete angular displacements, meaning that they are capable of turning a number of degrees (steps) depending on their control inputs.
These motors do not have brushes, their operation consists of a set of coils that, when electrically fed, depending on the intensity and which coils are fed, the rotor rotates at certain degrees.
This really is a bit more complex, it requires complex calculations to be able to move certain steps (or degrees), and it is even possible to move the rotor in micro steps, but for all this to be possible, the famous stepper motor drivers come into play.
What Is a Stepper Motor Driver?
The function of a driver to control a stepper motor is to generate all the necessary signals for motor operation, and also adds the necessary temperature and current protections.
As we mentioned before, the driver is used by the microcontroller to control the stepper motor and one of the advantages of these drivers is that only two microcontroller ports are needed to communicate with them.
There are some communication methods between controller and driver: Step/Direction, UART, SPI. Later we will tell you a little about them.
In the world of 3D printer drivers, we can find two types of drivers, plug & play and low-level.
Plug & Play Stepper Motor Drivers
These are drivers that can be connected directly to the PC, usually by USB cable.
These can be controlled and programmed directly by means of software and, in addition, they can work without more electronics, that is, they can work independently, requiring only the power supply as an extra element.
These drivers are not used in 3D printers on the market but can be used by makers to do personal printing or axis control projects.
Low-Level Stepper Motor Drivers
Low-level drivers are the ones you find most frequently in 3D printers. These drivers require basic control signals and to work, additional electronics such as microcontrollers are needed, this means that they are part of an embedded system, they are not used independently.
Many manufacturers of electronic boards for FDM 3D printers established a standard in the way these drivers are physically connected, usually consisting of a 2-strip 8-pin socket.
There are various features and specifications that these drivers have, we will name the most basic below:
- Operating voltages: Indicates the range of voltages with which it is capable of feeding the motor.
- Maximum output current per winding: The maximum current that is capable of continuously supplying each winding of the motor.
- Available microsteps: As we mentioned at the beginning, these motors move in steps. The most advanced drivers manage to divide these steps into microsteps, obtaining smaller and more precise movements, for example 1/8, 1/16, 1/32, some even reaching 1/256.
- Communication and control method: We usually talk about three communication methods.
- Step/Direction (Step/Dir): This is the simplest communication method the microcontroller communicates with the driver. It’s a one way communication, from the controller to the driver, but not the other way around, which means that some technologies and security systems cannot be used since the driver is not capable of sending information to the microcontroller.
- Step/Direction (Step/Dir): This communication method does allow communication in both directions, from the controller to the driver and from the driver to the microcontroller. This type of communication allows the controller to have information about the driver and the stepper motors.
- SPI: Like the UART, this communication method is bidirectional.
- Step/Direction (Step/Dir): This is the simplest communication method the microcontroller communicates with the driver. It’s a one way communication, from the controller to the driver, but not the other way around, which means that some technologies and security systems cannot be used since the driver is not capable of sending information to the microcontroller.
NOTE: Surely you are wondering about the difference between UART and SPI, they are simply different communication methods, it depends more than anything on the communicational compatibility between the microcontroller and the driver (although in a more technical sense, SPI is a protocol and UART is hardware). But both methods of communication are considered smart and allow the use of advanced proprietary technologies (which we’ll talk about later).
- Security mechanisms: These are mechanisms to provide protection to electronics and motors. This is achieved by monitoring and controlling such as over temperatures, overcurrents, and short circuits.
- Technological patents: Although we will talk a little more about this later, you should know that companies like Trinamic have interesting technological patents, for example, StealthChop the technology that has made it possible to greatly silence the noise generated by our 3D printers.
Stepper Motor Drivers That Have 3D Printers
Next, we will show the drivers for 3D printers in chronological order of appearance:
Driver A4988
The boom of budget FDM 3D printers began with this driver, which reached tremendous levels of popularity, both for use in 3D printers and in other types of equipment that use stepper motors, for example, CNCs and plotters.
There was no maker that did not know of the existence of this driver.
Technical Specifications of the A4988 Driver
- Driver: A4988
- Operating voltages: 8V to 32V
- Maximum output current per coil: 1A
- Available microsteps: 1/16
- Communication and control method: Step/Dir
- Safety mechanisms: Overcurrent, overtemperature, short circuit.
The following are some 3D printers that have the A4988 driver:
Driver DRV8825
Then the driver DRV8825 appeared with certain improvements over the A4988. This driver was capable of working with higher voltages, higher currents, and the ability to provide smaller microsteps.
Technical specifications of the DRV8825 driver
- Driver: DRV8825
- Operating voltages: 8.2V to 45V
- Maximum output current per coil: 1.5A
- Available microsteps: 1/32
- Communication and control method: Step/Dir
- Safety mechanisms: Overcurrent, overtemperature, short circuit.
Driver LV8729
This driver has the ability to work with microsteps up to 1/128. In addition, it is presented as an option to silence the noise generated by 3D printers, maintaining a good quality/price ratio.
Technical specifications of the LV8729 driver
- Driver: LV8729
- Operating voltages: 6V to 36V
- Maximum output current per coil: 1.5A
- Available microsteps: 1/128
- Communication and control method: Step/Dir
- Safety mechanisms: Overcurrent, overtemperature, short circuit.
- Technological patents: This is a silent driver
Drivers TMC
The Trinamic Motion Control drivers are the most popular in the world of 3D printing as they have very good technical features and very useful technological patents, such as noise reduction, and heat dissipation, among others.
The most used TMC drivers in 3D printers are the TMC2208, TMC2209, TMC2225, TMC2226, and TMC2660.
Next, we will show you the basic technical specifications of these drivers:
Technical specifications of the TMC2208 driver
- Driver: TMC2208
- Operating voltages: 5V to 36V
- Maximum output current per coil: 1.4A
- Available microsteps: 1/256
- Communication and control method: Step/Dir, UART
- Safety mechanisms: Overcurrent, overtemperature, short circuit.
- Technological patents: StealthChop (Silent), SpreadCycle, MicroPlyer.
The following are some 3D printers that have the TMC2208 driver:
Technical specifications of the TMC2209 driver
- Driver: TMC2209
- Operating voltages: 5V to 28V
- Maximum output current per coil: 2A
- Available microsteps: 1/256
- Communication and control method: Step/Dir, UART
- Safety mechanisms: Overcurrent, overtemperature, short circuit.
- Technological patents: StealthChop (Silent), SpreadCycle, MicroPlyer, StallGuard, CoolStep.
The following are some 3D printers that have the TMC2209 driver:
Technical Specifications of the TMC2225 Driver
- Driver: TMC2225
- Operating voltages: 5V to 36V
- Maximum output current per coil: 1.4A
- Available microsteps: 1/256
- Communication and control method: Step/Dir, UART
- Safety mechanisms: Overcurrent, overtemperature, short circuit.
- Technological patents: StealthChop (Silent), SpreadCycle, MicroPlyer, has better heat dissipation.
The following are some 3D printers that have the TMC2225 driver:
Technical Specifications of the TMC2226 Driver
- Driver: TMC2226
- Operating voltages: 5V to 29V
- Maximum output current per coil: 2A
- Available microsteps: 1/256
- Communication and control method: Step/Dir, UART
- Safety mechanisms: Overcurrent, overtemperature, short circuit.
- Technological patents: StealthChop (Silent), SpreadCycle, MicroPlyer, StallGuard, CoolStep, has better heat dissipation.
A 3D printer that uses this driver is the Biqu BX
Technical Specifications of the TMC2660 Driver
- Driver: TMC2660
- Operating voltages: 5V to 30V
- Maximum output current per coil: 2.8A
- Available microsteps: 1/256
- Communication and control method: Step/Dir, SPI
- Safety mechanisms: Overcurrent, overtemperature, short circuit.
- Technological patents: SpreadCycle, MicroPlyer, StallGuard, CoolStep.
Some 3D printers that use the TMC2660 driver are:
Differences Between TMC Drivers
The TMC2208 and TMC2209, have silent functionality, being the TMC2209 more advanced than the TMC2208 since the TMC2209 has more functionalities and supports more current.
The features and functionalities of the TMC2225 and TMC2226 are practically the same as those of the TMC2208 and TMC2209 respectively. The difference is that the TMC2225 and TMC2226 are better at dissipating heat than the TMC2208 and TMC2209.
So, we could say that the TMC2225 is a better heat-dissipating TMC2208 (but takes up more space), and the TMC2226 is a better heat-dissipating TMC2209 (but also takes up more space).
When the 3D printer manufacturer needs better heat dissipation, they turn to the TMC2225 and TMC2226.
The TMC2226 is more advanced than the TMC2225.
The TMC2660 driver is the driver that supports the most current of those mentioned above, for this reason we usually find this driver in larger 3D printers, which require the use of motors with greater torque.
Technologies and Patents of TMC Drivers
StallGuard: This technology allows the consumption of the motor to be measured, thus applying a method known as “Sensorless Homing”. This means that we are able to apply an autohome (send all the axes to the origin) without having to use any mechanical switch.
When the axes reach the origin and mechanically cannot move any further, the driver is capable of interpreting this as the zero position of any of the axes. Although for this it is necessary that the mechanical system of the printer be robust, firm and stable.
CoolStep: As with StallGuard, with CoolStep we are able to measure engine consumption without any additional sensors. But in this case, CoolStep seeks to manage the current correctly, supplying less current when the load is lower, meaning that, it supplies the appropriate current for certain moments, managing to reduce the heat generated in the motors by up to 80%.
StealthChop: This is probably the most popular technology of Trinamic Motion Control since it was thanks to it that we managed to silence our 3D printers, this marked a before and after in the world of 3D printing by FDM.
The interesting thing is that Trinamic managed to reduce the noise of the motors without harming the torque, but also managed to provide smoother movements.
SpreadCycle: This technology increases energy efficiency, in addition to giving us smoother transitions and movements, especially when we have to reduce acceleration to zero.
DcStep: With DcStep we are able to obtain extra torque by reducing the speed in cases where there are sudden and sharp increases in load, thus ensuring that we do not lose motor steps.
MicroPlyer: Thanks to MicroPlyer we are able to obtain micro steps up to 1/256, since MicroPlyer takes care of interpolating these steps.
SensOstep: This technology is accompanied by extra hardware that we must install on our stepper motors.
It is a sensor that allows us to detect the loss of steps, thus reducing the margin of error.
Most Famous Brands of 3D Printer Driver Manufacturers
- TMC (Trinamic Motion Control): The German company that produces the drivers that are currently the most popular in 3D printers, including the TMC2208, TMC2209, TMC2225, TMC2226, and TMC2660.
- Pololu / Allegro Microsystems: The American company Polulo produces cards that carry the Allegro A4988 driver. These drivers were practically the protagonists of the massification of 3D printers.
- Pololu / Texas Instruments: Once again Polulo produces cards that carry the DRV8825 driver from Texas Instruments. These drivers hit the market seeking to present an alternative with certain improvements over the famous A4988.
What Are the Most Used Drivers in 3D Printers?
Based on the database that we manage in our 3D printer comparator, we can make a small ranking of the most currently used drivers, based on the information shared by the manufacturers.
- TMC2209
- TMC2660
- TMC2225
- A4988
- TMC2208
Note: It is important to note that some manufacturers do not disclose information about the drivers they have for their 3D printers.
Modify the Power of Drivers in 3D Printers
The power that we are going to supply to our stepper motors can be modified with a potentiometer that’s found on the stepper motor driver.
This setting will depend on the driver and stepper motor used.
If you use a driver configured in intelligent mode (UART or SPI), this value can be adjusted digitally, through Gcode, but remember that this value will also be limited by the potentiometer, therefore, you should still make sure that the potentiometer is not at the minimum value.
If you set low power, the motor could lose steps. If you configure a lot of power, the motor will have more torque, but the motor and the driver will overheat, putting both at risk, and in the same way, due to overheating, you could lose steps.
Ideally, you should find out in forums and on the manufacturer’s website what is the optimal value for your 3D printer, since, depending on the mechanical and electrical characteristics of your printer, this value may change.
The idea is to use a value where the motors don’t lose steps and you don’t overheat the motors.
You also need to be very careful when adjusting the potentiometer, as you could accidentally short it out.
Impact of the Driver on the Score of the 3D Printer Comparator
If you enter our 3D printer comparator, you will notice that each 3D printer has a score that is based on its technical specifications.
The stepper motor driver used in a 3D printer is considered when obtaining the score of a 3D printer (among other tech specs).
So, if we compare two 3D printers with the same characteristics, but one printer has the A4988 driver and the other printer the TMC2209, our comparator will assign a higher score to the printer with the TMC2209, since this driver is more advanced, as we have seen and studied in this article.
The problem is that not all manufacturers explain or detail what driver their 3D printer has, so it is possible that some printer has a good driver, but they have never indicated it, in this case, the printer that does not have the driver information will lose some points.
In any case, in our comparator, although the driver does have an influence when assigning a score to the 3D printer, the reality is that it does not have a great impact on the ranking like other parameters (for example, the temperature that it is capable of reaching the extruder or the price). Since we are aware that on many occasions manufacturers do not provide all the technical information, and for some 3D printers, it is quite complex to obtain this information.
Conclusions About the Basic Guide of 3D Printer Drivers
Now you know a little more about the 3D printer drivers, and what function they fulfill.
You will understand that they are a fundamental part of this equipment and that thanks to them we have the technology to silence our 3D printers, obtain smoother and more fluid movements, lower energy consumption, smaller micro steps, and the ability to make an autohome without physical switches, among others.
We recently published another article related to our comparator and accessories for 3D printers, since our comparator shows the compatible accessories for some printers, if you want to take a look, we leave you the link next. The best accessories for your 3D printer.
If you are just starting out with 3D printing, or are already familiar with it, these three articles can be very useful:
- Most used 3D printing terms: In this article, you will learn about the terminology used in 3D printing.
- Beginner’s Guide of Simplify3D: Is designed for all those starting into the 3D printing world and interested in the slicer Simplify3D.
- Advanced Guide of Simplify3D: For those who already know the basics of Simplify3D but want to extend their knowledge on this Slicer.
Do not hesitate to leave any questions you have in our comments section, as well as any contribution or suggestion you wish to make, we are here to grow together in this wonderful world of 3D printing.
Greetings.
See you soon Machine Bros!
