This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

INL and DNL dual delfino question

Other Parts Discussed in Thread: TMS320F28377D

I read at page 47 of

SPRS880B –DECEMBER 2013–REVISED AUGUST 2014

at link http://www.ti.com/lit/gpn/tms320f28377d

and I don't understand how INL and DNL are equals to 12/16 bit modes

in the dual-delfino controller

Can someone help me

  • Hi Mauro,

    The linearity for both modes is specified in LSBs.  The LSB size is 16x smaller for 16-bit mode vs 12-bit mode, so the linearity specification is effectively 16x better for 16-bit mode vs 12-bit mode.

  • I don't understand how increasing number of bits

    in the same hardware

    linearity get better.

  • Hi Mauro,

    The ADC operates differently in 12-bit mode and 16-bit mode.  For example, notice that the S+H capacitor values specified in the documentation are different for these two modes and that the number of cycles required to convert a 16-bit value is much higher than that required to convert a 12-bit value (not just 4 more cycles for 4 more bits). 16-bit mode also benefits from linearity trim, while 12-bit mode can't use the trim correctly (see the errata).