Before probing into the TMC2208, it is also important to know what the stepper motor is, what the stepper motor driver is, and why a 3D printer needs them.
The stepper motor is one of the most common motors used in motion control applications, especially in positioning applications, because it can accurately be controlled down to fractions of a degree without the use of the feedback devices such as encoders or resolvers. The principle of stepper motors is straightforward. The traditional variable reluctance stepper motors have a large number of electromagnets arranged around a central gear-shaped a piece of iron. Electromagnets generate motions when energized because the central iron as a permanent magnet stimulates the electromagnets to move in a manner of stepper motion thus producing continuous rotation.
3D printers are adopting stepper motors to position axis so that the hotbed, build platform can be correctly positioned and the filament is exactly metered as it is extruded through the hot end. Stepper motors repeatedly make small movements in a fashion of fixed increments showing up as constant electric motor rotation. With stepper motor determining the size of each step, the stepper motor is exactly controlled by the stepper motor driver.
Fundamentally speaking, the stepper motor driver decides how precise the 3D printer can be.
Information about TMC2208
The TMC2208 provides an integrated motor driver solution for 3D-Printing. The device has an integrated micro-stepping indexer, the completely noiseless current control mode StealthChop2™ and is intended to drive a bipolar stepper motor. The output driver block consists of low RDSon N-Channel power MOSFETs configured as full H-bridges to drive the motor windings. Check the Block Diagram and its three different modes in the pictures below:
According to its original factory, the TMC2208 adopts the cutting-edge stealthChop™ technology to eliminate noise levels at low speeds. It is a monolithic component with integrated circuit breakers for up to 1.2A RMS, offering a resolution of up to 256 micro steps-per-full-steps to achieve perfect sinusoidal control - even with low-resolution motion controllers. Thus, it is such a perfect choice for the Creality CR-10 V2 3d printer to be equipped with a TMC2208 stepper motor driver that silent printing is an indisputable fact.
How Functional is TMC2208?
In this part, you could see how well the TMC2208 will perform in each mode. More information could be seen in the YouTube video by Teaching Tech.
Under mode 1: Teaching Tech tested the noise by doing a homing test, and the data is shown below.
Under mode 2: