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DRV8301-69M-KIT: DRV8301-69M-KIT

Mikael Sundberg
Intellectual 740 points
Part Number: DRV8301-69M-KIT


Hi,

We have been using the DRV8301-69M-KIT as a starting point for a higher current watercooled BLDC driver. Of course, using higher currents we have now found that using shunts is really not very accurate or easy to implement as the design grows conciderably. So after failing with this we are looking into using LEM- sensors, or specificly 2 HO 100-P/SP33-1106. But now the questions arise on how to implement them? We put them on phase A and B as we understand, change number of sensors in user.h to 2 sensors. Is it correct understanding that we scale them to match the currents we are using to 0-3.3V, with center at 1.65V at rest and then output them directly to the EXT_IA-FB and EXT_IA-FB pins seen in the schematics for DRV8301-69M-KIT? After we accomplish this we open the user.h and select 2 current sensors plus adjust the USER_ADC_FULL_SCALE_CURRENT_A according to our new sensors(250A), is this correct or do we need to do anything more or if we have missed something obvious?

We would appreciate very much if we could get a hint on how this is done or if we have thought this out corectly.

Best regards,

Mikael

  • 0
    TI__Guru** 116090 points
    As using current shunt resistor, the USER_ADC_FULL_SCALE_CURRENT is calculated based 0~3.3V range, so the USER_ADC_FULL_SCALE_CURRENT should be 500A since the measuring range of LEM sensor is -250A to +250A.
    You need to set the number of sensors to 2 if you only used LEM sensor on two phases.
  • 0 in reply to Yanming Luo
    Intellectual 740 points

    Ok, thanks Yanming for the tip, that is of course the way.

    The identification process runs well with this kind of setup using LEM sensors in your experience? Also, can you confirm using XT_IB-FA and XT_IB-FB pins are correct from the schematics found here: 



    Br,

    Mikael