SPRUHM9H October 2014 – May 2024 TMS320F28075 , TMS320F28075-Q1 , TMS320F28076
The internal DAC's reference voltage source, DACREF, is selectable between VDAC and VREFHI.
Two sets of DACVAL registers, DACVALA and DACVALS, are present in the buffered DAC module. DACVALA is a read-only register that actively controls the buffered DAC value. DACVALS is a writable shadow register that loads into DACVALA either immediately or synchronized with the next EPWMSYNCPER event. If the clock to the buffered DAC is disabled while the buffered DAC is outputting a voltage, the output voltage remains unaffected, but DACVALA and DACVALS is no longer updated with register writes. Enabling the clock to the buffered DAC restores the DAC to the state before the clock was disabled.
The output of the internal DAC is calculated with the following equation:
The output buffer of the buffered DAC can exhibit non-linear behavior near the supply rails (VDDA/VSSA). To determine the linear range of the buffered DAC, see the device-specific data sheet.