I don't understand the way ST specifies their current sense pin in the VNH7070 H-bridge motor driver, see the datasheet below.

How do I know what the current Isense will be? Why does the voltage Vsense remain the same for different currents, assuming Rsense will remain the same.

Why is the current Iout only specified for 0.05 to 5.5A, while the chip can deliver 15A?


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    \$\begingroup\$ It appears that the current ratio varies across output load, stabilising at around 3.5A out and becoming more accurate (or perhaps not as loose) with increasing loads. The K factor is explained a bit more at st.com/content/ccc/resource/technical/document/application_note/… \$\endgroup\$ Jun 12, 2019 at 9:30
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    \$\begingroup\$ See electronics.stackexchange.com/questions/443354/… for the answer to your question about Iout. \$\endgroup\$
    – srl100
    Jun 13, 2019 at 7:44
  • \$\begingroup\$ @srl100 Thank you for this answer. I did realize that the 15A would not be sustainable for very long times, although I did not realize this would only take miliseconds to reach shut-down temperatures. \$\endgroup\$ Jun 14, 2019 at 8:54


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