Hi, I am currently implementing software/firmware for the PowerSTEP01 chip and discovered a inconsistency in data sheet https://www.st.com/resource/en/datasheet/powerstep01.pdf. For parameter INT_SPEED (section 11.1.11 in datasheet) the equation does correspond to the stated limits.
It says:
i.e. steps/s = INT_SPEED × (2^−18) ÷ (250×10^−9)
- For smallest possible INT_SPEED=1 you get the minimum value:
steps/s = 1 × (2^−18) ÷ (250×10^−9) = 15.25
- For largest possible 14 bit value you get the maximum value:
step/s = (2^(14+1)−1) × (2^−18) ÷ (250×10^−9) = 499984.74
But according to datasheet equation results should be in range 0 < steps/s < 976.5.
So what is correct?
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1 ACCEPTED SOLUTION
Accepted Solutions
You are right, thank you for raising this issue. In fact, there is a typo in datasheet. The correct formula is:
i.e. steps/s = INT_SPEED × (2^−26) ÷ (250×10^−9)
Same mistake applies also to L6480 datasheet :persevering_face: , but at least L6470 datasheet is correct 🙂 . Control logic is the same for all 3 devices.
Mistake in datasheet will be corrected asap. Sorry for the inconvenience.
You are right, thank you for raising this issue. In fact, there is a typo in datasheet. The correct formula is:
i.e. steps/s = INT_SPEED × (2^−26) ÷ (250×10^−9)
Same mistake applies also to L6480 datasheet :persevering_face: , but at least L6470 datasheet is correct 🙂 . Control logic is the same for all 3 devices.
Mistake in datasheet will be corrected asap. Sorry for the inconvenience.
