Current Sense Board Revisions

Owned by Taiping Li
Last updated: Feb 02, 2018

Revision 1

  • Board size should be reduced by ~1-2mm on each side
    • Some deformation of the plastic housing was present when the current sensor arrived, so additional tolerances would be a good idea 
  • Fix polygon for SENSE_N on the input
  • Add a resistor divider (2k + 2k) on V- of the ADC to get Vref/2
    • The full scale of the ADC is Vref/2, not Vref as originally thought. Full scale of -2 to 2V differential can be obtained by biasing V- to 2V. This way V+ can span 0 - 4V, and  Vin = (V+ - V-) = -2 - 2V. The signum bit in the ADC's output data format (separate from 24 bit unsigned magnitude) is used to determine current direction.
  • Make test points closed on the stencil to avoid having solder on all the test points after reflowing
  • Add 0-ohms to switch isoSPI mode or tie it to mode 0
  • Add test point to V-