TMC6200 Max sensing current

Question

Hello, 
 
 I want to clarify this statement from the TMC6200 datasheet: 
 "Integrated current sense amplifiers eliminate costly sense amplifiers required for FOC controllers (recommended use for applications up to 10A, use external precision amplifiers for higher current with low sense resistor values), while bringing the benefit of in-line current sensing" 
 
 Performance of those amplifiers is limited to sense 10A (its not a function of sense resistor?)? 
 What about scenario when I want to sense 150A but with small Shunt Resistor of 0.5mOhm? Will I get resonable measurement or for sure those amplifiers will not work satisfactory? 
 
 Also, does those integrated amplifiers has some PWM-rejection filters? 
 
 Regards, 
 Adam

BernhardDwersteg · Accepted Answer

Hi, in principle you are right concerning the current - the TMC6200 does not care. But, in a practical use, a higher current motor has a much higher dynamics of motor current between unloaded and loaded situation. Therefore, you need a precise current sensing. The thermal drift of TMC6200 current sense limits the available precision. Therefore, we propose use of a dedicated current sense IC like AD8411.)

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TMC6200 Max sensing current