Datasheet

40 TMC223 DATASHEET (V. 1.00 / May 3rd, 2007)

7.2 Stall Detection Parameters

The timing parameter MinSamples has to be set depending on the PWM frequency and the chosen

velocity to the largest value below duration of on full step.

The stall detection blanking parameter FS2StallEN blanks variations of the BEMF due to oscillations

that follows an acceleration phase that can cause faulty detection of a stall.

The parameter AbsThr represents an absolute voltage level of the BEMF. The parameter DelThr

represents the difference (delta) threshold for processing of the BEMF based on the averaged BEMF

voltage.

In addition, there is one important switch named DC100En that should be set to one if the PWM come

close to 100%. With this, the stall detection is masked for PWM of 100%. This is because a PWM of

100% might faulty trigger the stall detection flags. On the other hand, a speed where the PWM duty

cycle comes close to 100% should be avoided. This is because a PWM duty cycle of 100% indicated

that the motor becomes within the zone where the torque decreases because the target current can

not be reached for that speed.

Delay Time [µs]

MinSamples

PWMfreq = 0

(PWM frequency typ 22.8 kHz)

PWMfreq = 1

(PWM frequency typ 45.6 kHz)

0x0 87 43

0x1 130 65

0x2 174 87

0x3 217 109

0x4 261 130

0x5 304 152

0x6 348 174

0x7 391 196

Table 17: Stall Detection Timing Parameter MinSamples

FS2StallEN Full Steps

0x0 0

0x1 1

0x2 2

0x3 3

0x4 4

0x5 5

0x6 6

0x7 7

Table 18: Stall Detection Blanking Parameter FS2StallEN