TMC2208 test (troubleshooting)

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TMC2208 test (troubleshooting) [Copy link]

TMC2208 Test Report

Table of contents

1. Problem review

2. Test platform display

3. Targeted testing

3.1. Standby current characteristics

3.2. Current characteristics of uniform process

4. Summary

1. Problem review
   In the last test, the standby current, micro-step smoothness, motor acceleration/deceleration, etc. were tested. It is not difficult to see that the current waveform is smooth and there is no distortion through the tested phase current waveform. However, the current fluctuation is large, and there are some burrs in the uniform speed stage. The initial inference is that it is due to the DuPont line, so I conducted another test.
2. The test platform is
   the same as the one used in the previous test. The only difference is that the DuPont cable is replaced with a new single DuPont cable for testing.
   
   Figure 1 Wiring diagram
3. Targeted testing
   1. Standby current characteristics
      Standby current (holding current when the motor is stationary) is tested by sampling and comparing with TMC5160. As can be seen from the figure below, the fluctuation of standby current of 2208 and 5160 is basically the same, both around ±60mA.
      
      Figure 2 TMC2208 phase current
      
      Figure 3 TMC2208 phase current
      
      Figure 4 TMC5160 phase current
      
      Figure 5 TMC5160 phase current
   2. The uniform process current characteristics
      in the standby current test, the performance after replacing the DuPont line is obvious. Therefore, I suspect that the burrs on the sine wave in the last test are also due to the DuPont line. From the comparison of Figure 6 and Figure 7, it can be seen that the burrs are significantly reduced after replacing the DuPont line.
      
      Figure 6 2208 uniform phase current
      
      Figure 7 Uniform phase current in "TMC2208 test (current characteristics)"
4. Summarize

From the two reports, we can see that the length of the MOS output line has a huge impact on the driving performance, and the reliability of the DuPont line also has certain problems. Through two tests, it was found that except for the SpreadCycle mode, which did not reach the ideal state, when the output current was the same, the performance of 2208 and 5160 was almost the same. This chip can be used in the design of small-sized special-shaped boards, but attention should be paid to heat dissipation.

zshasd1948

I have learned a lot. Good article. The content is explained in detail. Very good. Thank you.